Sumatriptan

INDICATIONS AND USAGE Sumatriptan injection is indicated in adults for (1) the acute treatment of migraine, with or without aura, and (2) the acute treatment of cluster headache. Limitations of Use: Use only if a clear diagnosis of migraine or cluster headache has been established. If a patient has no response to the first migraine or cluster headache attack treated with sumatriptan injection, reconsider the diagnosis before sumatriptan injection is administered to treat any subsequent attacks. Sumatriptan injection is not indicated for the prevention of migraine or cluster headache attacks. SUMATRIPTAN injection, for subcutaneous use Sumatriptan injection is a serotonin (5-HT1B/1D) receptor agonist (triptan) indicated for: Acute treatment of migraine with or without aura in adults. ( 1 ) Acute treatment of cluster headache in adults. ( 1 ) Limitations of Use: Use only if a clear diagnosis of migraine or cluster headache has been established. ( 1 ) Not indicated for the prophylactic therapy of migraine or cluster headache attacks. ( 1 )

DOSAGE AND ADMINISTRATION Recommended dose: 22 mg, administered by use of one nosepiece (11 mg) in each nostril ( 2.1 ) Maximum dose in a 24-hour period should not exceed two doses (44 mg) separated by at least 2 hours ( 2.1 ) 2.1 Dosing Information The recommended dosage of ONZETRA is 22 mg of sumatriptan nasal powder (2 nosepieces), administered using the Xsail breath-powered delivery device. If the migraine has not resolved by 2 hours after taking ONZETRA Xsail, or returns after a transient improvement, a second dose of 22 mg may be administered at least 2 hours after the first dose. The maximum recommended dose that may be given in 24 hours is two doses of ONZETRA Xsail (44 mg/4 nosepieces) or one dose of ONZETRA Xsail and one dose of another sumatriptan product, separated by at least 2 hours. The safety of treating an average of more than 4 headaches in a 30 day period has not been established. 2.2 Administration Instructions The recommended dose of 22 mg is administered by using one 11 mg nosepiece in each nostril [see Patient Counseling Information (17) ] . For administration of ONZETRA Xsail, the patient removes the clear device cap from the reusable delivery device, then removes a disposable nosepiece from its foil pouch and clicks the nosepiece into the device body. The patient then fully presses and promptly releases the white piercing button on the device body to pierce the capsule inside the nosepiece. The white piercing button should only be pressed once and released prior to administration to each nostril. The nosepiece is then inserted into the nostril so that it makes a tight seal. Keeping the nosepiece in the nose, the device is rotated to place the mouthpiece into the mouth. The patient blows forcefully through the mouthpiece to deliver the sumatriptan powder into the nasal cavity. Vibration (e.g., a rattling noise) may occur, and indicates that the patient is blowing forcefully, as directed. Once the medication in the first nosepiece has been administered, the patient removes and discards the nosepiece. The same process must then be repeated using a second 11 mg nosepiece into the other nostril to administer the remainder of the total recommended 22 mg dose [see Patient Counseling Information (17) ] .

WARNINGS AND PRECAUTIONS Myocardial ischemia/infarction and Prinzmetal’s angina: Perform cardiac evaluation in patients with multiple cardiovascular risk factors. ( 5.1 ) Arrhythmias: Discontinue sumatriptan nasal spray if occurs. ( 5.2 ) Chest/throat/neck/jaw pain, tightness, pressure, or heaviness: Generally not associated with myocardial ischemia; evaluate for coronary artery disease in patients at high risk. ( 5.3 ) Cerebral hemorrhage, subarachnoid hemorrhage, and stroke: Discontinue sumatriptan nasal spray if occurs. ( 5.4 ) Gastrointestinal ischemic reactions and peripheral vasospastic reactions: Discontinue sumatriptan nasal spray if occurs. ( 5.5 ) Medication overuse headache: Detoxification may be necessary. ( 5.6 ) Serotonin syndrome: Discontinue sumatriptan nasal spray if occurs. ( 5.7 ) Seizures: Use with caution in patients with epilepsy or a lowered seizure threshold. ( 5.11 ) 5.1 Myocardial Ischemia, Myocardial Infarction, and Prinzmetal’s Angina The use of sumatriptan nasal spray is contraindicated in patients with ischemic or vasospastic CAD. There have been rare reports of serious cardiac adverse reactions, including acute myocardial infarction, occurring within a few hours following administration of sumatriptan nasal spray. Some of these reactions occurred in patients without known CAD. Sumatriptan nasal spray may cause coronary artery vasospasm (Prinzmetal’s angina), even in patients without a history of CAD. Perform a cardiovascular evaluation in triptan-naive patients who have multiple cardiovascular risk factors (e.g., increased age, diabetes, hypertension, smoking, obesity, strong family history of CAD) prior to receiving sumatriptan nasal spray. If there is evidence of CAD or coronary artery vasospasm, sumatriptan nasal spray is contraindicated. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administering the first dose of sumatriptan nasal spray in a medically supervised setting and performing an electrocardiogram (ECG) immediately following administration of sumatriptan nasal spray. For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of sumatriptan nasal spray. 5.2 Arrhythmias Life-threatening disturbances of cardiac rhythm, including ventricular tachycardia and ventricular fibrillation leading to death, have been reported within a few hours following the administration of 5-HT 1 agonists. Discontinue sumatriptan nasal spray if these disturbances occur. Sumatriptan nasal spray is contraindicated in patients with Wolff-Parkinson-White syndrome or arrhythmias associated with other cardiac accessory conduction pathway disorders. 5.3 Chest, Throat, Neck, and/or Jaw Pain/Tightness/Pressure Sensations of tightness, pain, pressure, and heaviness in the precordium, throat, neck, and jaw may occur after treatment with sumatriptan nasal spray and are usually non-cardiac in origin. However, perform a cardiac evaluation if these patients are at high cardiac risk. The use of sumatriptan nasal spray is contraindicated in patients with CAD and those with Prinzmetal’s variant angina. 5.4 Cerebrovascular Events Cerebral hemorrhage, subarachnoid hemorrhage, and stroke have occurred in patients treated with 5-HT 1 agonists, and some have resulted in fatalities. In a number of cases, it appears possible that the cerebrovascular events were primary, the 5-HT 1 agonist having been administered in the incorrect belief that the symptoms experienced were a consequence of migraine when they were not. Also, patients with migraine may be at increased risk of certain cerebrovascular events (e.g., stroke, hemorrhage, TIA). Discontinue sumatriptan nasal spray if a cerebrovascular event occurs. Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with atypical symptoms, exclude other potentially serious neurological conditions. Sumatriptan nasal spray is contraindicated in patients with a history of stroke or TIA. 5.5 Other Vasospasm Reactions Sumatriptan nasal spray may cause non-coronary vasospastic reactions, such as peripheral vascular ischemia, gastrointestinal vascular ischemia and infarction (presenting with abdominal pain and bloody diarrhea), splenic infarction, and Raynaud’s syndrome. In patients who experience symptoms or signs suggestive of non-coronary vasospasm reaction following the use of any 5-HT 1 agonist, rule out a vasospastic reaction before using additional sumatriptan nasal spray. Reports of transient and permanent blindness and significant partial vision loss have been reported with the use of 5‑HT 1 agonists. Since visual disorders may be part of a migraine attack, a causal relationship between these events and the use of 5-HT 1 agonists have not been clearly established. 5.6 Medication Overuse Headache Overuse of acute migraine drugs (e.g., ergotamine, triptans, opioids, or combination of these drugs for 10 or more days per month) may lead to exacerbation of headache (medication overuse headache). Medication overuse headache may present as migraine-like daily headaches or as a marked increase in frequency of migraine attacks. Detoxification of patients, including withdrawal of the overused drugs, and treatment of withdrawal symptoms (which often includes a transient worsening of headache) may be necessary. 5.7 Serotonin Syndrome Serotonin syndrome may occur with sumatriptan nasal spray, particularly during co-administration with selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and MAO inhibitors [see Drug Interactions (7.4) ] . Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). The onset of symptoms usually occurs within minutes to hours of receiving a new or a greater dose of a serotonergic medication. Discontinue sumatriptan nasal spray if serotonin syndrome is suspected. 5.8 Increase in Blood Pressure Significant elevation in blood pressure, including hypertensive crisis with acute impairment of organ systems, has been reported on rare occasions in patients treated with 5-HT 1 agonists, including patients without a history of hypertension. Monitor blood pressure in patients treated with sumatriptan. Sumatriptan nasal spray is contraindicated in patients with uncontrolled hypertension. 5.9 Local Irritation Local irritative symptoms such as burning, numbness, paresthesia, discharge, and pain or soreness were reported in approximately 5% of patients in controlled clinical trials and were noted to be severe in about 1%. The symptoms were transient and generally resolved in less than 2 hours. Limited examinations of the nose and throat did not reveal any clinically noticeable injury in these patients. The consequences of extended and repeated use of sumatriptan nasal spray on the nasal and/or respiratory mucosa have not been systematically evaluated in patients. 5.10 Anaphylactic/Anaphylactoid Reactions Anaphylactic/anaphylactoid reactions have occurred in patients receiving sumatriptan. Such reactions can be life threatening or fatal. In general, anaphylactic reactions to drugs are more likely to occur in individuals with a history of sensitivity to multiple allergens. Sumatriptan nasal spray is contraindicated in patients with a history of hypersensitivity reaction to sumatriptan. 5.11 Seizures Seizures have been reported following administration of sumatriptan. Some have occurred in patients with either a history of seizures or concurrent conditions predisposing to seizures. There are also reports in patients where no such predisposing factors are apparent. Sumatriptan nasal spray should be used with caution in patie

CONTRAINDICATIONS Sumatriptan succinate tablets are contraindicated in patients with: • Ischemic coronary artery disease (CAD) (angina pectoris, history of myocardial infarction, or documented silent ischemia) or coronary artery vasospasm, including Prinzmetal's angina [see Warnings and Precautions ( 5.1 )] • Wolff-Parkinson-White syndrome or arrhythmias associated with other cardiac accessory conduction pathway disorders [see Warnings and Precautions ( 5.2 )] • History of stroke or transient ischemic attack (TIA) or history of hemiplegic or basilar migraine because these patients are at a higher risk of stroke [s ee Warnings and Precautions ( 5.4 )] • Peripheral vascular disease [see Warnings and Precautions ( 5.5 )] • Ischemic bowel disease [see Warnings and Precautions ( 5.5 )] • Uncontrolled hypertension [see Warnings and Precautions ( 5.8 )] • Recent use (i.e., within 24 hours) of ergotamine-containing medication, ergot-type medication (such as dihydroergotamine or methysergide), or another 5-hydroxytryptamine1 (5-HT 1 ) agonist [see Drug Interactions ( 7.1 , 7.3 )] • Concurrent administration of a monoamine oxidase (MAO)-A inhibitor or recent (within 2 weeks) use of an MAO-A inhibitor [see Drug Interactions ( 7.2 ), Clinical Pharmacology ( 12.3 )] • Hypersensitivity to sumatriptan succinate tablets (angioedema and anaphylaxis seen) [see Warnings and Precautions ( 5.9 )] • Severe hepatic impairment [see Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] • History of coronary artery disease or coronary artery vasospasm ( 4 ) • Wolff-Parkinson-White syndrome or other cardiac accessory conduction pathway disorders ( 4 ) • History of stroke, transient ischemic attack, or hemiplegic or basilar migraine ( 4 ) • Peripheral vascular disease ( 4 ) • Ischemic bowel disease ( 4 ) Uncontrolled hypertension ( 4 ) • Recent (within 24 hours) use of another 5-HT 1 agonist (e.g., another triptan) or of an ergotamine-containing medication. ( 4 ) • Concurrent or recent (past 2 weeks) use of monoamine oxidase-A inhibitor. ( 4 ) • Hypersensitivity to sumatriptan succinate tablets (angioedema and anaphylaxis seen). ( 4 ) • Severe hepatic impairment. ( 4 )

Drug Interactions Monoamine Oxidase Inhibitors (MAO) Treatment with MAO-A inhibitors generally leads to an increase of sumatriptan plasma levels (see CONTRAINDICATIONS and PRECAUTIONS ). Due to gut and hepatic metabolic first-pass effects, the increase of systemic exposure after coadministration of an MAO-A inhibitor with oral sumatriptan is greater than after coadministration of the monoamine oxidase inhibitors (MAOI) with subcutaneous sumatriptan. In a study of 14 healthy females, pretreatment with an MAO-A inhibitor decreased the clearance of subcutaneous sumatriptan. Under the conditions of this experiment, the result was a 2-fold increase in the area under the sumatriptan plasma concentration x time curve (AUC), corresponding to a 40% increase in elimination half-life. This interaction was not evident with an MAO-B inhibitor. A small study evaluating the effect of pretreatment with an MAO-A inhibitor on the bioavailability from a 25 mg oral sumatriptan tablet resulted in an approximately 7-fold increase in systemic exposure. Alcohol Alcohol consumed 30 minutes prior to sumatriptan ingestion had no effect on the pharmacokinetics of sumatriptan. Drug Interactions Selective Serotonin Reuptake Inhibitors/Serotonin Norepinephrine Reuptake Inhibitors and Serotonin Syndrome: Cases of life‑threatening serotonin syndrome have been reported during combined use of SSRIs or SNRIs and triptans (see WARNINGS ). Ergot-Containing Drugs Ergot-containing drugs have been reported to cause prolonged vasospastic reactions. Because there is a theoretical basis that these effects may be additive, use of ergotamine-containing or ergot-type medications (like dihydroergotamine or methysergide) and sumatriptan within 24 hours of each other should be avoided (see CONTRAINDICATIONS ). Monoamine Oxidase-A Inhibitors MAO-A inhibitors reduce sumatriptan clearance, significantly increasing systemic exposure. Therefore, the use of sumatriptan tablets in patients receiving MAO-A inhibitors is contraindicated (see CLINICAL PHARMACOLOGY and CONTRAINDICATIONS ).

ADVERSE REACTIONS Serious cardiac events, including some that have been fatal, have occurred following the use of sumatriptan succinate injection or tablets. These events are extremely rare and most have been reported in patients with risk factors predictive of CAD. Events reported have included coronary artery vasospasm, transient myocardial ischemia, myocardial infarction, ventricular tachycardia, and ventricular fibrillation (see CONTRAINDICATIONS , WARNINGS , and PRECAUTIONS ) . Significant hypertensive episodes, including hypertensive crises, have been reported on rare occasions in patients with or without a history of hypertension (see WARNINGS ). Incidence in Controlled Clinical Trials Table 2 lists adverse events that occurred in placebo-controlled clinical trials in patients who took at least 1 dose of study drug. Only events that occurred at a frequency of 2% or more in any group treated with sumatriptan tablets and were more frequent in that group than in the placebo group are included in Table 2. The events cited reflect experience gained under closely monitored conditions of clinical trials in a highly selected patient population. In actual clinical practice or in other clinical trials, these frequency estimates may not apply, as the conditions of use, reporting behavior, and the kinds of patients treated may differ. Table 2. Treatment Emergent Adverse Events Reported by at Least 2% of Patients in Controlled Migraine Trials a Adverse Event Type Percent of Patients Reporting Placebo (N = 309) Sumatriptan 25 mg (N = 417) Sumatriptan 50 mg (N = 771) Sumatriptan 100 mg (N = 437) Atypical sensations 4% 5% 6% 6% Paresthesia (all types) 2% 3% 5% 3% Sensation warm/cold 2% 3% 2% 3% Pain and other pressure sensations 4% 6% 6% 8% Chest - pain/tightness/pressure and/or heaviness 1% 1% 2% 2% Neck/throat/jaw - pain/ tightness/pressure <1% <1% 2% 3% Pain - location specified 1% 2% 1% 1% Other - pressure/tightness/ heaviness 2% 1% 1% 3% Neurological Vertigo <1% <1% <1% 2% Other Malaise/fatigue <1% 2% 2% 3% aEvents that occurred at a frequency of 2% or more in the group treated with sumatriptan tablets and that occurred more frequently in that group than the placebo group. Other events that occurred in more than 1% of patients receiving sumatriptan tablets and at least as often on placebo included nausea and/or vomiting, migraine, headache, hyposalivation, dizziness, and drowsiness/sleepiness. Sumatriptan tablets are generally well tolerated. Across all doses, most adverse reactions were mild and transient and did not lead to long-lasting effects. The incidence of adverse events in controlled clinical trials was not affected by gender or age of the patients. There were insufficient data to assess the impact of race on the incidence of adverse events. Other Events Observed in Association With the Administration of Sumatriptan Tablets In the paragraphs that follow, the frequencies of less commonly reported adverse clinical events are presented. Because the reports include events observed in open and uncontrolled studies, the role of sumatriptan tablets in their causation cannot be reliably determined. Furthermore, variability associated with adverse event reporting, the terminology used to describe adverse events, etc., limit the value of quantitative frequency estimates provided. Event frequencies are calculated as the number of patients who used sumatriptane tablets (25, 50, or 100 mg) and reported an event divided by the total number of patients (N = 6,348) exposed to sumatriptan tablets. All reported events are included except those already listed in the previous table, those too general to be informative, and those not reasonably associated with the use of the drug. Events are further classified within body system categories and enumerated in order of decreasing frequency using the following definitions: frequent adverse events are defined as those occurring in at least 1/100 patients, infrequent adverse events are those occurring in 1/100 to 1/1,000 patients, and rare adverse events are those occurring in fewer than 1/1,000 patients. Atypical Sensations Frequent were burning sensation and numbness. Infrequent was tight feeling in head. Rare were dysesthesia. Cardiovascular Frequent were palpitations, syncope, decreased blood pressure, and increased blood pressure. Infrequent were arrhythmia, changes in ECG, hypertension, hypotension, pallor, pulsating sensations, and tachycardia. Rare were angina, atherosclerosis, bradycardia, cerebral ischemia, cerebrovascular lesion, heart block, peripheral cyanosis, thrombosis, transient myocardial ischemia, and vasodilation. Ear, Nose, and Throat Frequent were sinusitis, tinnitus; allergic rhinitis; upper respiratory inflammation; ear, nose, and throat hemorrhage; external otitis; hearing loss; nasal inflammation; and sensitivity to noise. Infrequent were hearing disturbances and otalgia. Rare was feeling of fullness in the ear(s). Endocrine and Metabolic Infrequent was thirst. Rare were elevated thyrotropin stimulating hormone (TSH) levels; galactorrhea; hyperglycemia; hypoglycemia; hypothyroidism; polydipsia; weight gain; weight loss; endocrine cysts, lumps, and masses; and fluid disturbances. Eye Rare were disorders of sclera, mydriasis, blindness and low vision, visual disturbances, eye edema and swelling, eye irritation and itching, accommodation disorders, external ocular muscle disorders, eye hemorrhage, eye pain, and keratitis and conjunctivitis. Gastrointestinal Frequent were diarrhea and gastric symptoms. Infrequent were constipation, dysphagia, and gastroesophageal reflux. Rare were gastrointestinal bleeding, hematemesis, melena, peptic ulcer, gastrointestinal pain, dyspeptic symptoms, dental pain, feelings of gastrointestinal pressure, gastritis, gastroenteritis, hypersalivation, abdominal distention, oral itching and irritation, salivary gland swelling, and swallowing disorders. Hematological Disorders Rare was anemia. Musculoskeletal Frequent was myalgia. Infrequent was muscle cramps. Rare were tetany; muscle atrophy, weakness, and tiredness; arthralgia and articular rheumatitis; acquired musculoskeletal deformity; muscle stiffness, tightness, and rigidity; and musculoskeletal inflammation. Neurological Frequent were phonophobia and photophobia. Infrequent were confusion, depression, difficulty concentrating, disturbance of smell, dysarthria, euphoria, facial pain, heat sensitivity, incoordination, lacrimation, monoplegia, sleep disturbance, shivering, syncope, and tremor. Rare were aggressiveness, apathy, bradylogia, cluster headache, convulsions, decreased appetite, drug abuse, dystonic reaction, facial paralysis, hallucinations, hunger, hyperesthesia, hysteria, increased alertness, memory disturbance, neuralgia, paralysis, personality change, phobia, radiculopathy, rigidity, suicide, twitching, agitation, anxiety, depressive disorders, detachment, motor dysfunction, neurotic disorders, psychomotor disorders, taste disturbances, and raised intracranial pressure. Respiratory Frequent was dyspnea. Infrequent was asthma. Rare were hiccoughs, breathing disorders, cough, and bronchitis. Skin Frequent was sweating. Infrequent were erythema, pruritus, rash, and skin tenderness. Rare were dry/scaly skin, tightness of skin, wrinkling of skin, eczema, seborrheic dermatitis, and skin nodules. Breasts Infrequent was tenderness. Rare were nipple discharge; breast swelling; cysts, lumps, and masses of breasts; and primary malignant breast neoplasm. Urogenital Infrequent were dysmenorrhea, increased urination, and intermenstrual bleeding. Rare were abortion and hematuria, urinary frequency, bladder inflammation, micturition disorders, urethritis, urinary infections, menstruation symptoms, abnormal menstrual cycle, inflammation of fallopian tubes, and menstrual cycle symptoms. Miscellaneous Frequent was hypersensitivity. Infrequent were fever, fluid retention, and overdose. Rare were edema, hematoma, lymphadeno

CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Sumatriptan binds with high affinity to human cloned 5-HT 1B/1D receptors. Sumatriptan presumably exerts its therapeutic effects in the treatment of migraine headache through agonist effects at the 5-HT 1B/1D receptors on intracranial blood vessels and sensory nerves of the trigeminal system, which result in cranial vessel constriction and inhibition of pro-inflammatory neuropeptide release. 12.2 Pharmacodynamics Blood Pressure Significant elevation in blood pressure, including hypertensive crisis, has been reported in patients with and without a history of hypertension [see Warnings and Precautions (5.8) ]. Peripheral (Small) Arteries In healthy volunteers (N = 18), a trial evaluating the effects of sumatriptan on peripheral (small vessel) arterial reactivity failed to detect a clinically significant increase in peripheral resistance. Heart Rate Transient increases in blood pressure observed in some patients in clinical trials carried out during sumatriptan’s development as a treatment for migraine were not accompanied by any clinically significant changes in heart rate. 12.3 Pharmacokinetics Absorption The mean maximum concentration following oral dosing with 25 mg is 18 ng/mL (range: 7 to 47 ng/mL) and 51 ng/mL (range: 28 to 100 ng/mL) following oral dosing with 100 mg of sumatriptan. This compares with a C max of 5 and 16 ng/mL following dosing with a 5- and 20-mg intranasal dose, respectively. The mean C max following a 6-mg subcutaneous injection is 71 ng/mL (range: 49 to 110 ng/mL). The bioavailability is approximately 15%, primarily due to presystemic metabolism and partly due to incomplete absorption. The C max is similar during a migraine attack and during a migraine-free period, but the T max is slightly later during the attack, approximately 2.5 hours compared with 2.0 hours. When given as a single dose, sumatriptan displays dose proportionality in its extent of absorption (area under the curve [AUC]) over the dose range of 25 to 200 mg, but the C max after 100 mg is approximately 25% less than expected (based on the 25-mg dose). Effect of Food: A food effect trial involving administration of sumatriptan tablets 100 mg to healthy volunteers under fasting conditions and with a high-fat meal indicated that the C max and AUC were increased by 15% and 12%, respectively, when administered in the fed state. Distribution Protein binding, determined by equilibrium dialysis over the concentration range of 10 to 1,000 ng/mL is low, approximately 14% to 21%. The effect of sumatriptan on the protein binding of other drugs has not been evaluated. The apparent volume of distribution is 2.7 L/kg. Metabolism In vitro studies with human microsomes suggest that sumatriptan is metabolized by MAO, predominantly the A isoenzyme. Most of a radiolabeled dose of sumatriptan excreted in the urine is the major metabolite indole acetic acid (IAA) or the IAA glucuronide, both of which are inactive. Elimination The elimination half-life of sumatriptan is approximately 2.5 hours. Radiolabeled 14 C-sumatriptan administered orally is largely renally excreted (about 60%) with about 40% found in the feces. Most of the radiolabeled compound excreted in the urine is the major metabolite, IAA, which is inactive, or the IAA glucuronide. Only 3% of the doses can be recovered as unchanged sumatriptan. Specific Populations Age: The pharmacokinetics of sumatriptan in the elderly (mean age: 72 years, 2 males and 4 females) and in subjects with migraine (mean age: 38 years, 25 males and 155 females) were similar to that in healthy male subjects (mean age: 30 years). Patients with Renal Impairment: The effect of renal impairment on the pharmacokinetics of sumatriptan has not been examined. Patients with Hepatic Impairment: The liver plays an important role in the presystemic clearance of orally administered sumatriptan. Accordingly, the bioavailability of sumatriptan following oral administration may be markedly increased in patients with liver disease. In one small trial of patients with moderate liver impairment (n = 8) matched for sex, age, and weight with healthy subjects (n = 8), the hepatically-impaired patients had an approximately 70% increase in AUC and C max and a T max 40 minutes earlier compared with the healthy subjects. The pharmacokinetics of sumatriptan in patients with severe hepatic impairment has not been studied. The use of sumatriptan tablets in this population is contraindicated [see Contraindications (4) , Use in Specific Populations (8.6) ] . Male and Female Patients: In a trial comparing females to males, no pharmacokinetic differences were observed between genders for AUC, C max , T max , and half-life. Racial Groups: The systemic clearance and C max of subcutaneous sumatriptan were similar in black (n = 34) and Caucasian (n = 38) healthy male subjects. Oral sumatriptan has not been evaluated for race differences. Drug Interaction Studies Monoamine Oxidase-A Inhibitors : Treatment with MAO-A inhibitors generally leads to an increase of sumatriptan plasma levels [see Contraindications (4) , Drug Interactions (7.2) ] . Due to gut and hepatic metabolic first-pass effects, the increase of systemic exposure after coadministration of an MAO-A inhibitor with oral sumatriptan is greater than after coadministration of the MAO inhibitors with subcutaneous sumatriptan. In a trial of 14 healthy females, pretreatment with an MAO-A inhibitor decreased the clearance of subcutaneous sumatriptan, resulting in a 2-fold increase in the area under the sumatriptan plasma concentration-time curve (AUC), corresponding to a 40% increase in elimination half-life. A small trial evaluating the effect of pretreatment with an MAO-A inhibitor on the bioavailability from a 25-mg oral sumatriptan tablet resulted in an approximately 7-fold increase in systemic exposure. Alcohol: Alcohol consumed 30 minutes prior to sumatriptan ingestion had no effect on the pharmacokinetics of sumatriptan.