warnings and cautions
5 WARNINGS AND PRECAUTIONS Myocardial ischemia/infarction and Prinzmetal's angina: Perform cardiac evaluation in patients with multiple cardiovascular risk factors. ( 5.1 ) Arrhythmias: Discontinue naratriptan if occurs . ( 5.2 ) Chest/throat/neck/jaw pain, tightness, pressure, or heaviness: Generally not associated with myocardial ischemia; evaluate for CAD in patients at high risk. ( 5.3 ) Cerebral hemorrhage, subarachnoid hemorrhage, and stroke: Discontinue naratriptan if occurs . ( 5.4 ) Gastrointestinal ischemic reactions and peripheral vasospastic reactions: Discontinue naratriptan if occurs. ( 5.5 ) Medication overuse headache: Detoxification may be necessary. ( 5.6 ) Serotonin syndrome: Discontinue naratriptan if occurs. ( 5.7 ) 5.1 Myocardial Ischemia, Myocardial Infarction, and Prinzmetal's Angina Naratriptan 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 naratriptan. Some of these reactions occurred in patients without known CAD. Naratriptan 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 naratriptan. If there is evidence of CAD or coronary artery vasospasm, naratriptan is contraindicated. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administering the first dose of naratriptan in a medically supervised setting and performing an electrocardiogram (ECG) immediately following administration of naratriptan. For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of naratriptan. 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 naratriptan if these disturbances occur. Naratriptan 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, and pressure in the chest, throat, neck, and jaw commonly occur after treatment with naratriptan and are usually non-cardiac in origin. However, perform a cardiac evaluation if these patients are at high cardiac risk. 5-HT 1 agonists, including naratriptan, are 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 naratriptan if a cerebrovascular event occurs. Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with symptoms atypical for migraine, exclude other potentially serious neurological conditions. Naratriptan is contraindicated in patients with a history of stroke or TIA. 5.5 Other Vasospasm Reactions Naratriptan 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 receiving additional doses of naratriptan. 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 naratriptan, particularly during co-administration with selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and monoamine oxidase (MAO) inhibitors [see Drug Interactions (7.3) ]. 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 naratriptan 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 naratriptan. Naratriptan is contraindicated in patients with uncontrolled hypertension. 5.9 Anaphylactic Reactions There have been reports of anaphylaxis and hypersensitivity reactions, including angioedema, in patients receiving naratriptan. 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. Naratriptan is contraindicated in patients with a history of hypersensitivity reaction to naratriptan.