Side Effects of Relpax (eletriptan)

Migraine headaches are believed to result from abnormal brain activity that causes blood vessels on the surface of the brain and surrounding tissues to dilate.

The dilation of blood vessels is associated with inflammation. The triptan class of drugs, including Relpax, constricts blood vessels to prevent migraine headaches.

While highly effective in relieving migraines, Relpax does not prevent or reduce the frequency of attacks. It was shown to be more effective than sumatriptan in relieving migraine pain within two hours in a large study.

Common side effects of Relpax include:

Serious side effects of Relpax include:

• heart attacks,
• abnormal heartbeats,
• severe blood pressure elevation,
• stroke,
• bleeding, and
• seizures.

Relpax may interact with ergots (e.g., dihydroergotamine and ergotamine tartrate) or methysergide, causing blood vessel constriction. These effects may amplify the effects of Relpax.

• Ergot-containing drugs should not be used within 24 hours of Relpax.
• Ketoconazole, itraconazole, nefazodone, clarithromycin, ritonavir, and nelfinavir may increase Relpax levels in the blood by inhibiting an enzyme in the liver that eliminates Relpax.
• Relpax should not be taken within 72 hours of taking any of these medications.
• Other drugs that inhibit the same enzyme include diltiazem, Verapamil, fluconazole, voriconazole, indinavir, and erythromycin.

The safe use of Relpax during pregnancy and breastfeeding has not been established. Consult your doctor before breastfeeding.

Side Effects of Relpax (eletriptan)

Common side effects include:

• dizziness,
• nausea,
• weakness,
• tiredness,
• drowsiness,
• abdominal cramps, and
• chest, jaw, or neck pain.

More serious side effects include:

• heart attacks,
• abnormal heartbeats,
• severe blood pressure elevation,
• stroke,
• bleeding, and
• seizures.

Side Effects of Relpax (eletriptan) for Healthcare Professionals

The following adverse reactions are described in other sections of the prescribing information:

• Myocardial ischemia and myocardial infarction, and Prinzmetal’s angina
• Arrhythmias
• Chest, throat, neck, and/or jaw pain/tightness/pressure
• Cerebrovascular events
• Other vasospasm reactions
• Medication overuse headache
• Serotonin syndrome
• Increase in blood pressure
• Hypersensitivity reactions

Clinical Trials Experience

Because clinical studies are conducted under varying conditions, it is not possible to directly compare adverse reaction rates between drugs. The most common adverse reactions reported in short-term placebo-controlled trials with Relpax were asthenia, nausea, dizziness, and somnolence. These reactions appear to be dose-related.

In long-term open-label studies, where patients treated multiple migraine attacks for up to 1 year, 8.3% of patients discontinued treatment due to adverse reactions out of 1,544 patients.

Table 1 lists adverse reactions in patients who received eletriptan doses of 20 mg, 40 mg, and 80 mg or placebo in worldwide placebo-controlled clinical trials. Only adverse reactions that were more frequent in the Relpax treatment group with an incidence greater than or equal to 2% are included in Table 1.

Table 1: Adverse Reactions Incidence in Placebo-Controlled Migraine Clinical Trials: Reactions Reported by ≥ 2% Patients Treated with Relpax and More Than Placebo

The frequency of adverse reactions in clinical trials did not increase when up to 2 doses of Relpax were taken within 24 hours. The incidence of adverse reactions in controlled clinical trials was not affected by gender, age, or race of the patients.

Adverse reactions were also unchanged with concomitant use of drugs commonly taken for migraine prophylaxis (e.g., SSRIs, beta blockers, calcium channel blockers, tricyclic antidepressants), estrogen replacement therapy, or oral contraceptives.

Postmarketing Experience

The following adverse reactions have been reported after approval of Relpax. Due to the voluntary nature of these reports, it is not always possible to establish their frequency or a causal relationship to drug exposure.

Drug Interactions with Relpax (eletriptan)

Ergot-Containing Drugs Including Other 5-HT1B/1D Agonists

• Ergot-containing drugs have been reported to cause prolonged vasospastic reactions.
• Concurrent use of ergotamine-containing or ergot-type medications (e.g., dihydroergotamine [DHE] or methysergide) and Relpax within 24 hours is contraindicated due to potential additive effects.
• Concurrent use of other 5-HT1 agonists within 24 hours of Relpax treatment is contraindicated.

CYP3A4 Inhibitors

• Potent CYP3A4 inhibitors significantly increase Relpax exposure. Relpax should not be used within 72 hours of treatment with potent CYP3A4 inhibitors.

Selective Serotonin Reuptake Inhibitors/Serotonin And Norepinephrine Reuptake Inhibitors And Serotonin Syndrome

• Cases of serotonin syndrome have been reported during co-administration of triptans and SSRIs, SNRIs, TCAs, and MAO inhibitors.

Summary

Relpax is a triptan used for treating migraines. Common side effects include dizziness, nausea, weakness, tiredness, drowsiness, abdominal cramps, chest pain, jaw pain, and neck pain. Serious side effects include heart attacks, abnormal heartbeats, severe blood pressure elevation, stroke, bleeding, and seizures. The safe use of Relpax during pregnancy or while breastfeeding has not been established.