DURAGESIC (fentanyl transdermal system) is a transdermal system containing fentanyl. The chemical name is N-Phenyl-N-(1-(2-phenylethyl)-4-piperidinyl) propanamide. The structural formula is: The molecular weight of fentanyl base is 336.5, and the empirical formula is C22H28N2O. The n-octanol: water partition coefficient is 860:1. The pKa is 8.4. System Components and Structure The amount of fentanyl released from each system per hour is proportional to the surface area (25 mcg/h per 10.5 cm²). The composition per unit area of all system sizes is identical. Dose* (mcg/h) Size (cm²) Fentanyl Content (mg) 12** 5.25 2.1 25 10.5 4.2 50 21 8.4 75 31.5 12.6 100 42 16.8 **Nominal delivery rate per hour
***Nominal delivery rate is 12.5 mcg/hr DURAGESIC is a rectangular transparent unit comprising a protective liner and two functional layers. Proceeding from the outer surface toward the surface adhering to skin, these layers are: 1) a backing layer of polyester/ethyl vinyl acetate film; 2) a drug-in-adhesive layer. Before use, a protective liner covering the adhesive layer is removed and discarded.

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The following serious adverse reactions are discussed elsewhere in the labeling:

• Abuse Potential [see WARNINGS AND PRECAUTIONS]
• Respiratory Depression [see WARNINGS AND PRECAUTIONS]
• Accidental Exposure [see WARNINGS AND PRECAUTIONS]
• Elderly, Cachetic, and Debilitated Patients [see WARNINGS AND PRECAUTIONS]
• Chronic Pulmonary Disease [see WARNINGS AND PRECAUTIONS]
• Head Injuries and Increased Intracranial Pressure [see WARNINGS AND PRECAUTIONS]
• Interactions with Other CNS Depressants, Alcohol, and Drugs of Abuse [see WARNINGS AND PRECAUTIONS]
• Interactions with CYP3A4 Inhibitors [see WARNINGS AND PRECAUTIONS]
• Application of External Heat [see WARNINGS AND PRECAUTIONS]
• Patients with Fever [see WARNINGS AND PRECAUTIONS]
• Cardiac Disease [see WARNINGS AND PRECAUTIONS]
• Hepatic Impairment [see WARNINGS AND PRECAUTIONS]
• Renal Impairment [see WARNINGS AND PRECAUTIONS]
• Use in Pancreatic/Biliary Tract Disease [see WARNINGS AND PRECAUTIONS]
• Avoidance of Withdrawal [see WARNINGS AND PRECAUTIONS]
• Driving and Operating Machinery [see WARNINGS AND PRECAUTIONS]

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Clinical Trial Experience The safety of DURAGESIC was evaluated in 216 patients who took at least one dose of DURAGESIC in a multicenter, double-blind, randomized, placebo-controlled clinical trial of DURAGESIC. This trial examined patients over 40 years of age with severe pain induced by osteoarthritis of the hip or knee and who were in need of and waiting for joint replacement. The most common adverse reactions (≥5%) in a double-blind, randomized, placebo-controlled clinical trial in patients with severe pain were nausea, vomiting, somnolence, dizziness, insomnia, constipation, hyperhidrosis, fatigue, feeling cold, and anorexia. Other common adverse reactions (≥5%) reported in clinical trials in patients with chronic malignant or nonmalignant pain were headache and diarrhea. Adverse reactions reported for ≥1% of DURAGESIC-treated patients and with an incidence greater than placebo-treated patients are shown in Table 3. The most common adverse reactions that were associated with discontinuation in patients with pain (causing discontinuation in ≥1% of patients) were depression, dizziness, somnolence, headache, nausea, vomiting, constipation, hyperhidrosis, and fatigue. Table 3: Adverse Reactions Reported by ≥1% of DURAGESIC-treated Patients and With an Incidence Greater Than Placebo-treated Patients in 1 Double-Blind, Placebo-Controlled Clinical Trial of DURAGESIC
System/Organ Class
Adverse Reaction DURAGESIC %
(N=216) Placebo %
(N=200) Cardiac disorders Palpitations 4 1 Ear and labyrinth disorders Vertigo 2 1 Gastrointestinal disorders Nausea 41 17 Vomiting 26 3 Constipation 9 1 Abdominal pain upper 3 2 Dry mouth 2 0 General disorders and administration site conditions Fatigue 6 3 Feeling cold 6 2 Malaise 4 1 Asthenia 2 0 Edema peripheral 1 1 Metabolism and nutrition disorders Anorexia 5 0 Musculoskeletal and connective tissue disorders Muscle spasms 4 2 Nervous system disorders Somnolence 19 3 Dizziness 10 4 Psychiatric disorders Insomnia 10 7 Depression 1 0 Skin and subcutaneous tissue disorders Hyperhidrosis 6 1 Pruritus 3 2 Rash 2 1 Adverse reactions not reported in Table 1 that were reported by ≥1% of DURAGESIC-treated adult and pediatric patients (N=1854) in 11 controlled and uncontrolled clinical trials of DURAGESIC used for the treatment of chronic malignant or nonmalignant pain are shown in Table 4. Table 4: Adverse Reactions Reported by ≥1% of DURAGESIC-treated Patients in 11 Clinical Trials of DURAGESIC
System/Organ Class
Adverse Reaction DURAGESIC %
(N=1854) Gastrointestinal disorders Diarrhea 10 Abdominal pain 3 Immune system disorders Hypersensitivity 1 Nervous system disorders Headache 12 Tremor 3 Paresthesia 2 Psychiatric disorders Anxiety 3 Confusional state 2 Hallucination 1 Renal and urinary disorders Urinary retention 1 Skin and subcutaneous tissue disorders Erythema 1 The following adverse reactions occurred in adult and pediatric patients with an overall frequency of <1% and are listed in descending frequency within each System/Organ Class: Cardiac disorders: cyanosis Eye disorders: miosis Gastrointestinal disorders: subileus General disorders and administration site conditions: application site reaction, influenza-like illness, application site hypersensitivity, drug withdrawal syndrome, application site dermatitis Musculoskeletal and connective tissue disorders: muscle twitching Nervous system disorders: hypoesthesia Psychiatric disorders: disorientation, euphoric mood Reproductive system and breast disorders: erectile dysfunction, sexual dysfunction Respiratory, thoracic and mediastinal disorders: respiratory depression Skin and subcutaneous tissue disorders: eczema, dermatitis allergic, dermatitis contact Pediatrics The safety of DURAGESIC was evaluated in three open-label trials in 289 pediatric patients with chronic pain, 2 years of age through 18 years of age. Adverse reactions reported by ≥1% of DURAGESIC-treated pediatric patients are shown in Table 5. Table 5: Adverse Reactions Reported by ≥1% of DURAGESIC-treated Pediatric Patients in 3 Clinical Trials of DURAGESIC
System/Organ Class
Adverse Reaction DURAGESIC %
(N=289) Gastrointestinal disorders Vomiting 34 Nausea 24 Constipation 13 Diarrhea 13 Abdominal pain 9 Abdominal pain upper 4 Dry mouth 2 General disorders and administration site conditions Edema peripheral 5 Fatigue 2 Application site reaction 1 Asthenia 1 Immune system disorders Hypersensitivity 3 Metabolism and nutrition disorders Anorexia 4 Musculoskeletal and connective tissue disorders Muscle spasms 2 Nervous system disorders Headache 16 Somnolence 5 Dizziness 2 Tremor 2 Hypoesthesia 1 Psychiatric disorders Insomnia 6 Anxiety 4 Depression 2 Hallucination 2 Renal and urinary disorders Urinary retention 3 Respiratory, thoracic and mediastinal disorders Respiratory depression 1 Skin and subcutaneous tissue disorders Pruritus 13 Rash 6 Hyperhidrosis 3 Erythema 3 Post-Marketing Experience The following adverse reactions have been identified during post-approval use of DURAGESIC. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency. Cardiac Disorders: Tachycardia, Bradycardia Eye Disorders: Vision blurred Gastrointestinal Disorders: Ileus, Dyspepsia General Disorders and Administration Site Conditions: Feeling of body temperature change Immune System Disorders: Anaphylactic shock, Anaphylactic reaction, Anaphylactoid reaction Investigations: Weight decreased Nervous System Disorders: Convulsions (including Clonic convulsions and Grand mal convulsion), Amnesia Psychiatric Disorders: Agitation Respiratory, Thoracic, and Mediastinal Disorders: Respiratory distress, Apnea, Bradypnea, Hypoventilation, Dyspnea Vascular Disorders: Hypotension, Hypertension Read the Duragesic (fentanyl transdermal) Side Effects Center for a complete guide to possible side effectsLearn More »

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Proper Patient Selection Abuse Potential Assess patients for their clinical risks for opioid abuse or addiction prior to being prescribing DURAGESIC [see WARNINGS AND PRECAUTIONS]. Opioid Tolerance Opioid tolerance to an opioid of comparable potency must be established before prescribing DURAGESIC [see WARNINGS AND PRECAUTIONS]. Patients considered opioid-tolerant are those who are taking at least 60 mg of morphine daily, or at least 30 mg of oral oxycodone daily, or at least 8 mg of oral hydromorphone daily or an equianalgesic dose of another opioid for a week or longer. Dosing Conversion to DURAGESIC in Opioid-Tolerant Patients The recommended starting dose when converting from other opioids to DURAGESIC is intended to minimize the potential for overdosing patients with the first dose. Monitor patients closely for respiratory depression, especially within the first 24-72 hours of initiating therapy with DURAGESIC [see WARNINGS AND PRECAUTIONS]. In selecting an initial DURAGESIC dose, take the following factors into account:

1. the daily dose, potency, and characteristics of the opioid the patient has been taking previously (e.g., whether it is a pure agonist or mixed agonist-antagonist);
2. the reliability of the relative potency estimates used to calculate the DURAGESIC dose needed (potency estimates may vary with the route of administration);
3. the degree of opioid tolerance;
4. the general condition and medical status of the patient.

To convert adult and pediatric patients from oral or parenteral opioids to DURAGESIC, use Table 1. Do not use Table 1 to convert from DURAGESIC to other therapies because this conversion to DURAGESIC is conservative and will overestimate the dose of the new agent. TABLE 11: DOSE CONVERSION GUIDELINES
Current Analgesic Daily Dosage (mg/day) Oral morphine 60-134 135-224 225-314 315-404 Intramuscular or Intravenous morphine 10-22 23-37 38-52 53-67 Oral oxycodone 30-67 67.5-112 112.5-157 157.5-202 Oral codeine 150-447 Oral hydromorphone 8-17 17.1-28 28.1-39 39.1-51 Intravenous hydromorphone 1.5-3.4 3.5-5.6 5.7-7.9 8-10 Intramuscular meperidine 75-165 166-278 279-390 391-503 Oral methadone 20-44 45-74 75-104 105-134   ⇓ ⇓ ⇓ ⇓ Recommended 25 mcg/hour 50 mcg/hour 75 mcg/hour 100 mcg/hour Alternatively, for adult and pediatric patients taking opioids or doses not listed in Table 1, use the conversion methodology outlined above with Table 2.
1Table 1 should not be used to convert from DURAGESIC to other therapies because this conversion to DURAGESIC is conservative. Use of Table 1 for conversion to other analgesic therapies can overestimate the dose of the new agent. Overdosage of the new analgesic agent is possible [see Titration and Maintenance of Therapy]. Alternatively, for adult and pediatric patients taking opioids or doses not listed in Table 1, use the following methodology:

1. Calculate the previous 24-hour analgesic requirement.
2. Convert this amount to the equianalgesic oral morphine dose using a reliable reference.
   Refer to Table 2 for the range of 24-hour oral morphine doses that are recommended for conversion to each DURAGESIC dose. Use this table to find the calculated 24-hour morphine dose and the corresponding DURAGESIC dose. Initiate DURAGESIC treatment using the recommended dose and titrate patients upwards (no more frequently than 3 days after the initial dose and every 6 days thereafter) until analgesic efficacy is attained.
3. Do not use Table 2 to convert from DURAGESIC to other therapies because this conversion to DURAGESIC is conservative and will overestimate the dose of the new agent.

TABLE 21: RECOMMENDED INITIAL DURAGESIC DOSE BASED UPON DAILY ORAL MORPHINE DOSE
Oral 24-hour Morphine (mg/day) DURAGESIC Dose (mcg/hour) 60-134 25 135-224 50 225-314 75 315-404 100 405-494 125 495-584 150 585-674 175 675-764 200 765-854 225 855-944 250 945-1034 275 1035-1124 300 NOTE: In clinical trials, these ranges of daily oral morphine doses were used as a basis for conversion to DURAGESIC.
1Table 2 should not be used to convert from DURAGESIC to other therapies because this conversion to DURAGESIC is conservative. Use of Table 2 for conversion to other analgesic therapies can overestimate the dose of the new agent. Overdosage of the new analgesic agent is possible [see Titration and Maintenance of Therapy]. For delivery rates in excess of 100 mcg/hour, multiple systems may be used. Hepatic Impairment Avoid the use of DURAGESIC in patients with severe hepatic impairment. In patients with mild to moderate hepatic impairment, start with one half of the usual dosage of DURAGESIC. Closely monitor for signs of sedation and respiratory depression, including at each dosage increase [see WARNINGS AND PRECAUTIONS, Use In Specific Populations and CLINICAL PHARMACOLOGY]. Renal Impairment Avoid the use of DURAGESIC in patients with severe renal impairment. In patients with mild to moderate renal impairment, start with one half of the usual dosage of DURAGESIC. Closely monitor for signs of sedation and respiratory depression, including at each dosage increase [see WARNINGS AND PRECAUTIONS, Use In Specific Populations and CLINICAL PHARMACOLOGY]. Titration and Maintenance of Therapy Once therapy is initiated, assess pain intensity and opioid adverse reactions frequently, especially respiratory depression [see WARNINGS AND PRECAUTIONS]. Routinely monitor all patients for signs of misuse, abuse and addiction [see WARNINGS AND PRECAUTIONS]. The initial DURAGESIC dose may be increased after 3 days based on the daily dose of supplemental opioid analgesics required by the patient on the second or third day of the initial application. It may take up to 6 days for fentanyl levels to reach equilibrium on a new dose [see CLINICAL PHARMACOLOGY]. Therefore, evaluate patients for further titration after no less than two 3-day applications before any further increase in dosage is made. Base dosage increments on the daily dosage of supplementary opioids, using the ratio of 45 mg/24 hours of oral morphine to a 12 mcg/hour increase in DURAGESIC dose. The majority of patients are adequately maintained with DURAGESIC administered every 72 hours. Some patients may not achieve adequate analgesia using this dosing interval and may require systems to be applied at 48 hours rather than at 72 hours, only if adequate pain control cannot be achieved using a 72-hour regimen. An increase in the DURAGESIC dose should be evaluated before changing dosing intervals in order to maintain patients on a 72-hour regimen. Dosing intervals less than every 72 hours were not studied in children and adolescents and are not recommended. Discontinuation of DURAGESIC To convert patients to another opioid, remove DURAGESIC and titrate the dose of the new analgesic based upon the patient's report of pain until adequate analgesia has been attained. Upon system removal, 17 hours or more are required for a 50% decrease in serum fentanyl concentrations. Withdrawal symptoms are possible in some patients after conversion or dose adjustment [see WARNINGS AND PRECAUTIONS]. Do not use Tables 1 and 2 to convert from DURAGESIC to other therapies to avoid overestimating the dose of the new agent potentially resulting in overdose of the new analgesic and death. When discontinuing DURAGESIC and not converting to another opioid, use a gradual downward titration, such as halving the dose every 6 days, in order to reduce the possibility of withdrawal symptoms [see WARNINGS AND PRECAUTIONS]. It is not known at what dose level DURAGESIC may be discontinued without producing the signs and symptoms of opioid withdrawal. Administration of DURAGESIC DURAGESIC patches are for transdermal use, only. Proper handling of DURAGESIC is advised in order to prevent adverse reactions, including death, associated with accidental secondary exposure to DURAGESIC [see WARNINGS AND PRECAUTIONS]. Application and Handling Instructions

• Patients should apply DURAGESIC to intact, non-irritated, and non-irradiated skin on a flat surface such as the chest, back, flank, or upper arm. In young children and persons with cognitive impairment, adhesion should be monitored and the upper back is the preferred location to minimize the potential of inappropriate patch removal. Hair at the application site may be clipped (not shaved) prior to system application. If the site of DURAGESIC application must be cleansed prior to application of the patch, do so with clear water. Do not use soaps, oils, lotions, alcohol, or any other agents that might irritate the skin or alter its characteristics. Allow the skin to dry completely prior to patch application.
• Patients should apply DURAGESIC immediately upon removal from the sealed package. The patch must not be altered (e.g., cut) in any way prior to application. DURAGESIC should not be used if the pouch seal is broken or if the patch is cut or damaged.
• The transdermal system is pressed firmly in place with the palm of the hand for 30 seconds, making sure the contact is complete, especially around the edges.
• Each DURAGESIC patch may be worn continuously for 72 hours. The next patch is applied to a different skin site after removal of the previous transdermal system.
• If problems with adhesion of the DURAGESIC patch occur, the edges of the patch may be taped with first aid tape. If problems with adhesion persist, the patch may be overlayed with a transparent adhesive film dressing.
• If the patch falls off before 72 hours, dispose of it by folding in half and flushing down the toilet. A new patch may be applied to a different skin site.
• Patients (or caregivers who apply DURAGESIC) should wash their hands immediately with soap and water after applying DURAGESIC.
• Contact with unwashed or unclothed application sites can result in secondary exposure to DURAGESIC and should be avoided. Examples of accidental exposure include transfer of a DURAGESIC patch from an adult's body to a child while hugging, sharing the same bed as the patient, accidental sitting on a patch and possible accidental exposure of a caregiver's skin to the medication in the patch while applying or removing the patch.
• Instruct patients, family members, and caregivers to keep patches in a secure location out of the reach of children and of others for whom DURAGESIC was not prescribed.

Avoidance of Heat Instruct patients to avoid exposing the DURAGESIC application site and surrounding area to direct external heat sources, such as heating pads or electric blankets, heat or tanning lamps, sunbathing, hot baths, saunas, hot tubs, and heated water beds, while wearing the system [see WARNINGS AND PRECAUTIONS]. Disposal Instructions Proper disposal of DURAGESIC is advised in order to prevent adverse reactions, including death, associated with accidental secondary exposure to DURAGESIC [see WARNINGS AND PRECAUTIONS]. Patients should dispose of used patches by folding the adhesive side of the patch to itself, then flush the patch down the toilet immediately upon removal. Patients should dispose of any patches remaining from a prescription as soon as they are no longer needed. Unused patches should be removed from their pouches, fold so that the adhesive side of the patch adheres to itself, and flush down the toilet.

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Agents Affecting Cytochrome P450 3A4 Isoenzyme System Fentanyl is metabolized mainly via the human cytochrome P450 3A4 isoenzyme system (CYP3A4). Coadministration with agents that induce CYP3A4 activity may reduce the efficacy of DURAGESIC. The concomitant use of DURAGESIC with a CYP3A4 inhibitor (such as ritonavir, ketoconazole, itraconazole, troleandomycin, clarithromycin, nelfanivir, nefazadone, amiodarone, amprenavir, aprepitant, diltiazem, erythromycin, fluconazole, fosamprenavir, verapamil, or grapefruit juice) may result in an increase in fentanyl plasma concentrations, which could increase or prolong adverse drug effects and may cause fatal respiratory depression. Closely monitor patients receiving DURAGESIC and any CYP3A4 inhibitor and reduce the dosage of DURAGESIC if warranted [see CLINICAL PHARMACOLOGY]. Central Nervous System Depressants The concomitant use of DURAGESIC with other central nervous system depressants, including but not limited to other opioids, sedatives, hypnotics, tranquilizers (e.g., benzodiazepines), general anesthetics, phenothiazines, skeletal muscle relaxants, and alcohol, may cause respiratory depression, hypotension, and profound sedation, or potentially result in coma or death. Monitor patients closely when central nervous system depressants are used concomitantly with DURAGESIC and reduce the dose of one or both agents. MAO Inhibitors Avoid use of DURAGESIC in the patient who would require the concomitant administration of a monoamine oxidase (MAO) inhibitor, or within 14 days of stopping such treatment because severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. Drug Abuse And Dependence Controlled Substance DURAGESIC contains fentanyl, a potent Schedule II opioid agonist. Schedule II opioid substances, which include hydromorphone, methadone, morphine, oxycodone, and oxymorphone, have the highest potential for abuse and risk of fatal overdose due to respiratory depression. DURAGESIC can be abused and is subject to criminal diversion [see WARNINGS AND PRECAUTIONS]. Abuse Addiction is a primary, chronic, neurobiologic disease, with genetic, psychosocial, and environmental factors influencing its development and manifestations. It is characterized by behaviors that include one or more of the following: impaired control over drug use, compulsive use, continued use despite harm, and craving. Drug addiction is a treatable disease, utilizing a multidisciplinary approach, but relapse is common. “Drug seeking” behavior is very common in addicts and drug abusers. Drug-seeking tactics include emergency calls or visits near the end of office hours, refusal to undergo appropriate examination, testing or referral, repeated “loss” of prescriptions, tampering with prescriptions and reluctance to provide prior medical records or contact information for other treating physician(s). “Doctor shopping” to obtain additional prescriptions is common among drug abusers and people suffering from untreated addiction. Abuse and addiction are separate and distinct from physical dependence and tolerance. Physicians should be aware that addiction may be accompanied by concurrent tolerance and symptoms of physical dependence. In addition, abuse of opioids can occur in the absence of true addiction and is characterized by misuse for non-medical purposes, often in combination with other psychoactive substances. Since DURAGESIC may be diverted for non-medical use, careful recordkeeping of prescribing information, including quantity, frequency, and renewal requests is strongly advised. Proper assessment of the patient, proper prescribing practices, periodic reevaluation of therapy, and proper dispensing and storage are appropriate measures that help to limit abuse of opioid drugs. Dependence Tolerance is a state of adaptation in which exposure to a drug induces changes that result in a diminution of one or more of the drug's effects over time. Tolerance may occur to both the desired and undesired effects of drugs, and may develop at different rates for different effects. Physical dependence is a state of adaptation that is manifested by an opioid specific withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, decreasing blood concentration of the drug, and/or administration of an antagonist. The opioid abstinence or withdrawal syndrome is characterized by some or all of the following: restlessness, lacrimation, rhinorrhea, yawning, perspiration, chills, piloerection, myalgia, mydriasis, irritability, anxiety, backache, joint pain, weakness, abdominal cramps, insomnia, nausea, anorexia, vomiting, diarrhea, or increased blood pressure, respiratory rate, or heart rate. In general, opioids should not be abruptly discontinued [see DOSAGE AND ADMINISTRATION]. Last reviewed on RxList: 10/29/2013
This monograph has been modified to include the generic and brand name in many instances.

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DURAGESIC is a transdermal formulation of fentanyl indicated for the management of persistent, moderate to severe chronic pain in opioid-tolerant patients 2 years of age and older when a continuous, around-the-clock opioid analgesic is required for an extended period of time, and the patient cannot be managed by other means such as non-steroidal analgesics, opioid combination products, or immediate-release opioids. Patients considered opioid-tolerant are those who are taking at least 60 mg of morphine daily, or at least 30 mg of oral oxycodone daily, or at least 8 mg of oral hydromorphone daily, or an equianalgesic dose of another opioid for a week or longer.

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DURAGESIC is contraindicated in the following patients and situations due to the risk of fatal respiratory depression:

• in patients who are not opioid-tolerant [see WARNINGS AND PRECAUTIONS].
• in the management of acute or intermittent pain, or in patients who require opioid analgesia for a short period of time [see WARNINGS AND PRECAUTIONS].
• in the management of post-operative pain, including use after out-patient or day surgeries, (e.g., tonsillectomies) [see WARNINGS AND PRECAUTIONS].
• in the management of mild pain [see WARNINGS AND PRECAUTIONS].
• in patients with significant respiratory compromise, especially if adequate monitoring and resuscitative equipment are not readily available [see WARNINGS AND PRECAUTIONS].
• in patients who have acute or severe bronchial asthma [see WARNINGS AND PRECAUTIONS].

DURAGESIC is also contraindicated:

• in patients who have or are suspected of having paralytic ileus
• in patients with known hypersensitivity to fentanyl or any components of the transdermal system. Severe hypersensitivity reactions, including anaphylaxis have been observed with DURAGESIC [see ADVERSE REACTIONS].

Last reviewed on RxList: 10/29/2013
This monograph has been modified to include the generic and brand name in many instances.

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Clinical Presentation Acute overdosage with opioids can be manifested by respiratory depression, somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and sometimes bradycardia, hypotension and death. The pharmacokinetic characteristics of DURAGESIC must also be taken into account when treating the overdose. Even in the face of improvement, continued medical monitoring is required because of the possibility of extended effects. Deaths due to overdose have been reported with abuse and misuse of DURAGESIC. Treatment Give primary attention to the reestablishment of a patent airway and institution of assisted or controlled ventilation. Employ supportive measures (including oxygen and vasopressors) in the management of circulatory shock and pulmonary edema accompanying overdose as indicated. Cardiac arrest or arrhythmias will require advanced life support techniques. Remove all DURAGESIC systems. The pure opioid antagonists, such as naloxone, are specific antidotes to respiratory depression from opioid overdose. Since the duration of reversal is expected to be less than the duration of action of fentanyl, carefully monitor the patient until spontaneous respiration is reliably reestablished. After DURAGESIC system removal, serum fentanyl concentrations decline gradually, falling about 50% in approximately 20-27 hours. Therefore, management of an overdose must be monitored accordingly, at least 72 to 96 hours beyond the overdose. Only administer opioid antagonists in the presence of clinically significant respiratory or circulatory depression secondary to hydromorphone overdose. In patients who are physically dependent on any opioid agonist including DURAGESIC, an abrupt or complete reversal of opioid effects may precipitate an acute abstinence syndrome. The severity of the withdrawal syndrome produced will depend on the degree of physical dependence and the dose of the antagonist administered. Please see the prescribing information for the specific opioid antagonist for details of their proper use.

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Dosage Forms And Strengths DURAGESIC is available as:

• DURAGESIC 12 mcg/hour* Transdermal System (system size 5.25 cm²).
• DURAGESIC 25 mcg/hour Transdermal System (system size 10.5 cm²).
• DURAGESIC 50 mcg/hour Transdermal System (system size 21 cm²).
• DURAGESIC 75 mcg/hour Transdermal System (system size 31.5 cm²).
• DURAGESIC 100 mcg/hour Transdermal System (system size 42 cm²).

*This lowest dosage is designated as 12 mcg/hour (however, the actual dosage is 12.5 mcg/hour) to distinguish it from a 125 mcg/h dosage that could be prescribed by multiple patches. Storage And Handling DURAGESIC (fentanyl transdermal system) is supplied in cartons containing 5 individually packaged systems. See chart for information regarding individual systems. DURAGESIC Dose (mcg/h) System Size (cm²) Fentanyl Content (mg) NDC Number DURAGESIC-12* 5.25 2.1 50458-090-05 DURAGESIC-25 10.5 4.2 50458-091-05 DURAGESIC-50 21 8.4 50458-092-05 DURAGESIC-75 31.5 12.6 50458-093-05 DURAGESIC-100 42 16.8 50458-094-05 *This lowest dosage is designated as 12 mcg/h (however, the actual dosage is 12.5 mcg/h) to distinguish it from a 125 mcg/h dosage that could be prescribed by using multiple patches. Store in original unopened pouch. Store up to 25°C (77°F); excursions permitted to 15 -30°C (59 -86°F). Manufactured by: ALZA Corporation, Vacaville, CA 95688. Manufactured for: Janssen Pharmaceuticals, Inc., Titusville, NJ 08560. Sep 2013. Last reviewed on RxList: 10/29/2013
This monograph has been modified to include the generic and brand name in many instances.

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Abuse Potential DURAGESIC contains fentanyl, an opioid agonist and a Schedule II controlled substance with an abuse liability similar to other opioid analgesics. Schedule II opioid substances which include hydromorphone, morphine, oxycodone, fentanyl, oxymorphone and methadone have the highest potential for abuse and risk of fatal overdose due to respiratory depression. DURAGESIC can be abused in a manner similar to other opioid agonists, legal or illicit. These risks should be considered when administering, prescribing, or dispensing DURAGESIC in situations where the healthcare professional is concerned about increased risk of misuse, abuse, or diversion [see Drug Abuse and Dependence]. Assess patients for their clinical risks for opioid abuse or addiction prior to being prescribed opioids. Routinely monitor all patients receiving opioids for signs of misuse, abuse and addiction since use of opioid analgesic products carries the risk of addiction even under appropriate medical use. Persons at increased risk for opioid abuse include those with a personal or family history of substance abuse (including drug or alcohol abuse or addiction) or mental illness (e.g., major depression). Patients at increased risk may still be appropriately treated with modified-release opioid formulations; however these patients will require intensive monitoring for signs of misuse, abuse, or addiction. Concerns about abuse, addiction, and diversion should not prevent the proper management of pain. Contact local state professional licensing board or state controlled substances authority for information on how to prevent and detect abuse or diversion of this product. Respiratory Depression and Death Respiratory depression is the chief hazard of DURAGESIC. Respiratory depression, if not immediately recognized and treated, may lead to respiratory arrest and death. DURAGESIC has a narrow indication and should be prescribed only by healthcare professionals who are knowledgeable in the administration of potent opioids and management of chronic pain [see INDICATIONS AND USAGE]. DURAGESIC is contraindicated for use in conditions in which the risk of life-threatening respiratory depression is significantly increased, including use as an as-needed analgesic, use in non-opioid tolerant patients, acute pain, and postoperative pain [see CONTRAINDICATIONS]. Proper dosing and titration of DURAGESIC are essential [see DOSAGE AND ADMINISTRATION ]. Overestimating the DURAGESIC dose when converting patients from another opioid medication, can result in fatal overdose with the first dose. However, respiratory depression has also been reported with use of DURAGESIC in patients who are opioid-tolerant, even when DURAGESIC has been used as recommended and not misused or abused. The mean half-life of fentanyl when delivered by DURAGESIC is approximately 20-27 hours. Serum fentanyl concentrations continue to rise for the first two system applications. In addition, significant amounts of fentanyl continue to be absorbed from the skin for 24 hours or more after the patch is removed [see CLINICAL PHARMACOLOGY]. Respiratory depression from opioids is manifested by a reduced urge to breathe and a decreased rate of respiration, often associated with a “sighing” pattern of breathing (deep breaths separated by abnormally long pauses). Carbon dioxide retention from opioid-induced respiratory depression can exacerbate the sedating effects of opioids. While serious, life-threatening or fatal respiratory depression can occur at any time during the use of DURAGESIC, the potential for serious, life threatening, or fatal respiratory depression is greatest during the first two applications following initiation of dosing, or following an increase in dosage. Closely monitor patients for respiratory depression when initiating therapy with DURAGESIC, especially within the initial 24-72 hours when serum concentrations from the initial patch will peak, and following increases in dosage. Because significant amounts of fentanyl continue to be absorbed from the skin for 24 hours or more after the patch is removed, respiratory depression may persist beyond the removal of DURAGESIC. Monitor patients for respiratory depression after patch removal to ensure that the patient's respiration has stabilized for at least 24 to 72 hours or longer as clinical symptoms dictate. Management of respiratory depression may include close observation, supportive measures, and use of opioid antagonists, depending on the patient's clinical status [see OVERDOSE]. Accidental Exposure A considerable amount of active fentanyl remains in DURAGESIC even after use as directed. Death and other serious medical problems have occurred when children and adults were accidentally exposed to DURAGESIC. Accidental or deliberate application or ingestion by a child or adolescent will cause respiratory depression that could result in death. Placing DURAGESIC in the mouth, chewing it, swallowing it, or using it in ways other than indicated may cause choking or overdose that could result in death. Advise patients about strict adherence to the recommended handling and disposal instructions in order to prevent accidental exposure to DURAGESIC (see DOSAGE AND ADMINISTRATION]. Elderly, Cachectic, and Debilitated Patients Respiratory depression is more likely to occur in elderly, cachectic, or debilitated patients as they may have altered pharmacokinetics due to poor fat stores, muscle wasting, or altered clearance. Therefore, monitor these patients closely, particularly when initiating therapy with DURAGESIC and when given in conjunction with other drugs that depress respiration [see Use in Specific Populations]. Chronic Pulmonary Disease Monitor patients with significant chronic obstructive pulmonary disease or cor pulmonale, and patients having a substantially decreased respiratory reserve, hypoxia, hypercapnia, or pre-existing respiratory depression for respiratory depression, particularly when initiating therapy with DURAGESIC, as in these patients, even usual therapeutic doses of DURAGESIC may decrease respiratory drive to the point of apnea. Consider the use of alternative non-opioid analgesics in these patients if possible. Head Injuries and Increased Intracranial Pressure Avoid use of DURAGESIC in patients who may be particularly susceptible to the intracranial effects of CO2 retention such as those with evidence of increased intracranial pressure, impaired consciousness, or coma. In addition, opioids may obscure the clinical course of patients with head injury. Monitor patients with brain tumors who may be susceptible to the intracranial effects of CO2 retention for signs of sedation and respiratory depression, particularly when initiating therapy with DURAGESIC, as DURAGESIC may reduce respiratory drive and CO2 retention can further increase intracranial pressure. Interactions with Other CNS Depressants, Alcohol, and Drugs of Abuse The concomitant use of DURAGESIC with other central nervous system depressants, including, but not limited to, other opioids, sedatives, hypnotics, tranquilizers (e.g., benzodiazepines), general anesthetics, phenothiazines, skeletal muscle relaxants, and alcohol, may cause respiratory depression, hypotension, and profound sedation or coma. Monitor patients prescribed concomitant CNS active drugs for signs of sedation and respiratory depression, particularly when initiating therapy with DURAGESIC, and reduce the dose of one or both agents. Interactions with CYP3A4 Inhibitors The concomitant use of DURAGESIC with a CYP3A4 inhibitors (such as ritonavir, ketoconazole, itraconazole, troleandomycin, clarithromycin, nelfinavir, nefazadone, amiodarone, amprenavir, aprepitant, diltiazem, erythromycin, fluconazole, fosamprenavir, verapamil) may result in an increase in fentanyl plasma concentrations, which could increase or prolong adverse drug effects and may cause potentially fatal respiratory depression. Carefully monitor patients receiving DURAGESIC and any CYP3A4 inhibitor for signs of sedation and respiratory depression for an extended period of time, and make dosage adjustments if warranted [see DRUG INTERACTIONS and CLINICAL PHARMACOLOGY]. Application of External Heat Exposure to heat may increase fentanyl absorption and there have been reports of overdose and death as a result of exposure to heat. A clinical pharmacology study conducted in healthy adult subjects has shown that the application of heat over the DURAGESIC system increased fentanyl exposure [see CLINICAL PHARMACOLOGY]. Warn patients to avoid exposing the DURAGESIC application site and surrounding area to direct external heat sources [see DOSAGE AND ADMINISTRATION]. Patients with Fever Based on a pharmacokinetic model, serum fentanyl concentrations could theoretically increase by approximately one-third for patients with a body temperature of 40°C (104°F) due to temperature-dependent increases in fentanyl released from the system and increased skin permeability. Monitor patients wearing DURAGESIC systems who develop fever closely for opioid side effects and reduce the DURAGESIC dose if necessary. Warn patients to avoid strenuous exertion that leads to increased core body temperature while wearing DURAGESIC to avoid the risk of potential overdose and death. Cardiac Disease DURAGESIC may produce bradycardia. Monitor patients with bradyarrhythmias closely for changes in heart rate, particularly when initiating therapy with DURAGESIC. Hepatic Impairment A clinical pharmacology study with DURAGESIC in patients with cirrhosis has shown that systemic fentanyl exposure increased in these patients. Because of the long half-life of fentanyl when administered as DURAGESIC and hepatic metabolism of fentanyl, avoid use of DURAGESIC in patients with severe hepatic impairment. Insufficient information exists to make precise dosing recommendations regarding the use of DURAGESIC in patients with impaired hepatic function. Therefore, to avoid starting patients with mild to moderate hepatic impairment on too high of a dose, start with one half of the usual dosage of DURAGESIC. Closely monitor for signs of sedation and respiratory depression, including at each dosage increase. [see DOSING AND ADMINISTRATION, Use In Specific Populations and CLINICAL PHARMACOLOGY]. Renal Impairment A clinical pharmacology study with intravenous fentanyl in patients undergoing kidney transplantation has shown that patients with high blood urea nitrogen level had low fentanyl clearance. Because of the long half-life of fentanyl when administered as DURAGESIC, avoid the use of DURAGESIC in patients with severe renal impairment. Insufficient information exists to make precise dosing recommendations regarding the use of DURAGESIC in patients with impaired renal function. Therefore, to avoid starting patients with mild to moderate renal impairment on too high of a dose, start with one half of the usual dosage of DURAGESIC. Closely monitor for signs of sedation and respiratory depression, including at each dosage increase [see DOSING AND ADMINISTRATION, Use In Specific Populations and CLINICAL PHARMACOLOGY]. Use in Pancreatic/Biliary Tract Disease DURAGESIC may cause spasm of the sphincter of Oddi. Monitor patients with biliary tract disease, including acute pancreatitis for worsened symptoms. DURAGESIC may cause increases in the serum amylase concentration. Avoidance of Withdrawal Opioid withdrawal symptoms (such as nausea, vomiting, diarrhea, anxiety, and shivering) are possible in some patients after conversion to another opioid or when decreasing or discontinuing DURAGESIC. Gradual reduction of the dose of DURAGESIC is recommended [see DOSAGE AND ADMINISTRATION and Drug Abuse and Dependence]. Driving and Operating Machinery Strong opioid analgesics impair the mental or physical abilities required for the performance of potentially dangerous tasks, such as driving a car or operating machinery. Warn patients not to drive or operate dangerous machinery unless they are tolerant to the effects of the DURAGESIC. Patient Counseling Information See FDA-approved patient labeling (Medication Guide and Instructions for Use) Provide patients receiving DURAGESIC patches the following information:

• DURAGESIC patches contain fentanyl, an opioid pain medicine that can cause serious breathing problems and death, especially if used in the wrong way and therefore should be taken only as directed. Instruct patients to call their doctor immediately or seek emergency medical help if they experience breathing problems while taking DURAGESIC.
• DURAGESIC contains fentanyl which has a high potential for abuse. Instruct patients, family members, and caregivers to protect DURAGESIC from theft or misuse in the work or home environment.
• Instruct patients to never give DURAGESIC to anyone other than the individual for whom it was prescribed because of the risk of death or other serious medical problems to that person for whom it was not intended.
• Advise patients never to change the dose of DURAGESIC or the number of patches applied to the skin unless instructed to do so by the prescribing healthcare professional.
• Warn patients of the potential for temperature-dependent increases in fentanyl release from the patch that could result in an overdose of fentanyl. Instruct patients to contact their healthcare provider if they develop a high fever. Instruct patients to:
  • avoid strenuous exertion that can increase body temperature while wearing the patch
  • avoid exposing the DURAGESIC application site and surrounding area to direct external heat sources including heating pads, electric blankets, sunbathing, heat or tanning lamps, saunas, hot tubs or hot baths, and heated water beds.
• Keep DURAGESIC in a secure place out of the reach of children due to the high risk of fatal respiratory depression. DURAGESIC can be accidentally transferred to children. Instruct patients to take special precautions to avoid accidental contact when holding or caring for children.
• If the patch dislodges and accidentally sticks to the skin of another person, to immediately take the patch off, wash the exposed area with water and seek medical attention for the accidentally exposed individual as accidental exposure may lead to death or other serious medical problems.
• To properly disposal of used and unneeded, unused DURAGESIC, remove them from their pouches, fold them so that the adhesive side of the patch adheres to itself, and flush them down the toilet.
• DURAGESIC may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating machinery). Instruct patients to refrain from any potentially dangerous activity when starting on DURAGESIC or when their dose is being adjusted, until it is established that they have not been adversely affected.
• Advise women of childbearing potential who become, or are planning to become pregnant, to consult a healthcare provider prior to initiating or continuing therapy with DURAGESIC.
• Instruct patients not to use alcohol or other CNS depressants (e.g. sleep medications, tranquilizers) while using DURAGESIC because dangerous additive effects may occur, resulting in serious injury or death.
• Advise patients of the potential for severe constipation.
• When no longer needed, DURAGESIC should not be stopped abruptly to avoid the risk of precipitating withdrawal symptoms.

Nonclinical Toxicology Carcinogenesis, Mutagenesis, and Impairment of Fertility Carcinogenesis In a two-year carcinogenicity study conducted in rats, fentanyl was not associated with an increased incidence of tumors at subcutaneous doses up to 33 μg/kg/day in males or 100 μg/kg/day in females (0.16 and 0.39 times the human daily exposure obtained via the 100 mcg/h patch based on AUC0-24h comparison). Mutagenesis There was no evidence of mutagenicity in the Ames Salmonella mutagenicity assay, the primary rat hepatocyte unscheduled DNA synthesis assay, the BALB/c 3T3 transformation test, and the human lymphocyte and CHO chromosomal aberration in-vitro assays. Impairment of Fertility The potential effects of fentanyl on male and female fertility were examined in the rat model via two separate experiments. In the male fertility study, male rats were treated with fentanyl (0, 0.025, 0.1 or 0.4 mg/kg/day) via continuous intravenous infusion for 28 days prior to mating; female rats were not treated. In the female fertility study, female rats were treated with fentanyl (0, 0.025, 0.1 or 0.4 mg/kg/day) via continuous intravenous infusion for 14 days prior to mating until day 16 of pregnancy; male rats were not treated. Analysis of fertility parameters in both studies indicated that an intravenous dose of fentanyl up to 0.4 mg/kg/day to either the male or the female alone produced no effects on fertility (this dose is approximately 1.6 times the daily human dose administered by a 100 mcg/hr patch on a mg/m² basis). In a separate study, a single daily bolus dose of fentanyl was shown to impair fertility in rats when given in intravenous doses of 0.3 times the human dose for a period of 12 days. Use In Specific Populations Pregnancy Teratogenic Effects Pregnancy C: There are no adequate and well-controlled studies in pregnant women. DURAGESIC should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. The potential effects of fentanyl on embryo-fetal development were studied in the rat, mouse, and rabbit models. Published literature reports that administration of fentanyl (0, 10, 100, or 500 μg/kg/day) to pregnant female Sprague-Dawley rats from day 7 to 21 via implanted microosmotic minipumps did not produce any evidence of teratogenicity (the high dose is approximately 2 times the daily human dose administered by a 100 mcg/hr patch on a mg/m² basis). In contrast, the intravenous administration of fentanyl (0, 0.01, or 0.03 mg/kg) to bred female rats from gestation day 6 to 18 suggested evidence of embryotoxicity and a slight increase in mean delivery time in the 0.03 mg/kg/day group. There was no clear evidence of teratogenicity noted. Pregnant female New Zealand White rabbits were treated with fentanyl (0, 0.025, 0.1, 0.4 mg/kg) via intravenous infusion from day 6 to day 18 of pregnancy. Fentanyl produced a slight decrease in the body weight of the live fetuses at the high dose, which may be attributed to maternal toxicity. Under the conditions of the assay, there was no evidence for fentanyl induced adverse effects on embryo-fetal development at doses up to 0.4 mg/kg (approximately 3 times the daily human dose administered by a 100 mcg/hr patch on a mg/m² basis). Nonteratogenic Effects Chronic maternal treatment with fentanyl during pregnancy has been associated with transient respiratory depression, behavioral changes, or seizures characteristic of neonatal abstinence syndrome in newborn infants. Symptoms of neonatal respiratory or neurological depression were no more frequent than expected in most studies of infants born to women treated acutely during labor with intravenous or epidural fentanyl. Transient neonatal muscular rigidity has been observed in infants whose mothers were treated with intravenous fentanyl. The potential effects of fentanyl on prenatal and postnatal development were examined in the rat model. Female Wistar rats were treated with 0, 0.025, 0.1, or 0.4 mg/kg/day fentanyl via intravenous infusion from day 6 of pregnancy through 3 weeks of lactation. Fentanyl treatment (0.4 mg/kg/day) significantly decreased body weight in male and female pups and also decreased survival in pups at day 4. Both the mid-dose and high-dose of fentanyl animals demonstrated alterations in some physical landmarks of development (delayed incisor eruption and eye opening) and transient behavioral development (decreased locomotor activity at day 28 which recovered by day 50). The mid-dose and the high-dose are 0.4 and 1.6 times the daily human dose administered by a 100 mcg/hr patch on a mg/m² basis. Labor and Delivery Fentanyl readily passes across the placenta to the fetus; therefore, DURAGESIC is not recommended for analgesia during labor and delivery. Nursing Mothers Fentanyl is excreted in human milk; therefore, DURAGESIC is not recommended for use in nursing women because of the possibility of effects in their infants. Pediatric Use The safety of DURAGESIC was evaluated in three open-label trials in 289 pediatric patients with chronic pain, 2 years of age through 18 years of age. Starting doses of 25 mcg/h and higher were used by 181 patients who had been on prior daily opioid doses of at least 45 mg/day of oral morphine or an equianalgesic dose of another opioid. Initiation of DURAGESIC therapy in pediatric patients taking less than 60 mg/day of oral morphine or an equianalgesic dose of another opioid has not been evaluated in controlled clinical trials. The safety and effectiveness of DURAGESIC in children under 2 years of age have not been established. To guard against excessive exposure to DURAGESIC by young children, advise caregivers to strictly adhere to recommended DURAGESIC application and disposal instructions [see DOSAGE AND ADMINISTRATION and WARNINGS AND PRECAUTIONS]. Geriatric Use Clinical studies of DURAGESIC did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy. Data from intravenous studies with fentanyl suggest that the elderly patients may have reduced clearance and a prolonged half-life. Moreover, elderly patients may be more sensitive to the active substance than younger patients. A study conducted with the DURAGESIC patch in elderly patients demonstrated that fentanyl pharmacokinetics did not differ significantly from young adult subjects, although peak serum concentrations tended to be lower and mean half-life values were prolonged to approximately 34 hours [see CLINICAL PHARMACOLOGY]. Monitor geriatric patients closely for signs of sedation and respiratory depression, particularly when initiating therapy with DURAGESIC and when given in conjunction with other drugs that depress respiration [see WARNINGS AND PRECAUTIONS]. Hepatic Impairment The effect of hepatic impairment on the pharmacokinetics of DURAGESIC has not been fully evaluated. A clinical pharmacology study with DURAGESIC in patients with cirrhosis has shown that systemic fentanyl exposure increased in these patients. Because there is in-vitro and in-vivo evidence of extensive hepatic contribution to the elimination of DURAGESIC, hepatic impairment would be expected to have significant effects on the pharmacokinetics of DURAGESIC. Avoid use of DURAGESIC in patients with severe hepatic impairment [see DOSING AND ADMINISTRATION, WARNINGS AND PRECAUTIONS and CLINICAL PHARMACOLOGY]. Renal Impairment The effect of renal impairment on the pharmacokinetics of DURAGESIC has not been fully evaluated. A clinical pharmacology study with intravenous fentanyl in patients undergoing kidney transplantation has shown that patients with high blood urea nitrogen level had low fentanyl clearance. Because there is in-vivo evidence of renal contribution to the elimination of DURAGESIC, renal impairment would be expected to have significant effects on the pharmacokinetics of DURAGESIC. Avoid the use of DURAGESIC in patients with severe renal impairment [see DOSING AND ADMINISTRATION, WARNINGS AND PRECAUTIONS and CLINICAL PHARMACOLOGY]. Neonatal Opioid Withdrawal Syndrome Chronic maternal use of fentanyl can affect the neonate with subsequent withdrawal signs. Neonatal withdrawal syndrome presents as irritability, hyperactivity, and abnormal sleep pattern, high pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. The onset, duration and severity of neonatal withdrawal syndrome vary based on the drug used, duration of use, the dosage of last maternal use, and rate of elimination of the drug by the newborn. Neonatal opioid withdrawal syndrome, unlike opioid withdrawal syndrome in adults, may be life-threatening and should be treated according to protocols developed by neonatology experts. Last reviewed on RxList: 10/29/2013
This monograph has been modified to include the generic and brand name in many instances.

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