5 WARNINGS AND PRECAUTIONS
RELPAX should only be used where a clear diagnosis of migraine has been established.
5.1 Myocardial Ischemia, Myocardial Infarction, and Prinzmetal's Angina
RELPAX 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 RELPAX. Some of these reactions occurred in patients without known CAD. RELPAX may cause coronary artery vasospasm (Prinzmetal's angina), even in patients without a history of CAD.
Perform a cardiovascular evaluation in triptan-naïve patients who have multiple cardiovascular risk factors (e.g., increased age, diabetes, hypertension, smoking, obesity, strong family history of CAD) prior to receiving RELPAX. Do not use RELPAX if there is evidence of CAD or coronary artery vasospasm [see Contraindications (4)]. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administering the first RELPAX dose in a medically-supervised setting and performing an electrocardiogram (ECG) immediately following administration of RELPAX. For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of RELPAX.
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-HT1 agonists. Discontinue RELPAX if these disturbances occur. RELPAX is contraindicated in patients with Wolff-Parkinson-White syndrome or arrhythmias associated with other cardiac accessory conduction pathway disorders [see Contraindications (4)].
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 RELPAX and are usually non-cardiac in origin. However, perform a cardiac evaluation if these patients are at high cardiac risk. RELPAX is contraindicated in patients with CAD or Prinzmetal's variant angina [see Contraindications (4)].
5.4 Cerebrovascular Events
Cerebral hemorrhage, subarachnoid hemorrhage, and stroke have occurred in patients treated with 5-HT1 agonists, and some have resulted in fatalities. In a number of cases, it appears possible that the cerebrovascular events were primary, the 5-HT1 agonist having been administered in the incorrect belief that the symptoms experienced were a consequence of migraine, when they were not.
Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with symptoms atypical of migraine, other potentially serious neurological conditions need to be excluded. RELPAX is contraindicated in patients with a history of stroke or TIA [see Contraindications (4)].
5.5 Other Vasospasm Reactions
RELPAX may cause non-coronary vasospastic reactions, such as peripheral vascular ischemia, gastrointestinal vascular ischemia and infarction (presenting with abdominal pain and bloody diarrhea), and Raynaud's syndrome. In patients who experience symptoms or signs suggestive of a vasospastic reaction following the use of any 5-HT1 agonist, rule out a vasospastic reaction before receiving additional RELPAX doses [see Contraindications (4)].
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 acute migraine 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 RELPAX, particularly during co-administration with selective serotonin reuptake inhibitors (SSRIs), serotonin and 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 RELPAX 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-HT1 agonists, including patients without a history of hypertension. Monitor blood pressure in patients treated with RELPAX. RELPAX is contraindicated in patients with uncontrolled hypertension [see Contraindications (4)].
5.9 Anaphylactic/Anaphylactoid Reactions
There have been reports of anaphylaxis, anaphylactoid, and hypersensitivity reactions including angioedema in patients receiving RELPAX. 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. RELPAX is contraindicated in patients with a history of hypersensitivity reaction to RELPAX [see Contraindications (4)].