Relpax (Eletriptan Hydrobromide) - Drug Interactions, Contraindications, Overdosage

DRUG INTERACTIONS

Ergot-containing drugs

Ergot-containing drugs have been reported to cause prolonged vasospastic reactions. Because these effects may be additive, use of ergotamine-containing or ergot-type medications (like dihydroergotamine [DHE] or methysergide) and eletriptan within 24 hours of each other is not recommended (see CONTRAINDICATIONS).

CYP3A4 Inhibitors

Eletriptan is metabolized primarily by CYP3A4 (see WARNINGS regarding use with potent CYP3A4 inhibitors).

Monoamine Oxidase Inhibitors

Eletriptan is not a substrate for monoamine oxidase (MAO) enzymes; therefore, there is no expectation of an interaction between eletriptan and MAO inhibitors.

Propranolol

The C_max and AUC of eletriptan were increased by 10 and 33% respectively in the presence of propranolol. No interactive increases in blood pressure were observed. No dosage adjustment appears to be needed for patients taking propranolol (see CLINICAL PHARMACOLOGY).

Selective Serotonin Reuptake Inhibitors/Serotonin Norepinephrine Reuptake Inhibitors and Serotonin Syndrome

Cases of life-threatening serotonin syndrome have been reported during combined use of selective serotonin reuptake inhibitors (SSRIs) or serotonin norepinephrine reuptake inhibitors (SNRIs) and triptans (See WARNINGS).

Other 5-HT₁ agonists

Concomitant use of other 5-HT₁ agonists within 24 hours of RELPAX treatment is not recommended (see CONTRAINDICATIONS).

OVERDOSAGE

No significant overdoses in premarketing clinical trials have been reported. Volunteers (N=21) have received single doses of 120 mg without significant adverse effects. Daily doses of 160 mg were commonly employed in Phase III trials. Based on the pharmacology of the 5-HT_1B/1D agonists, hypertension or other more serious cardiovascular symptoms could occur on overdose.

The elimination half-life of eletriptan is about 4 hours (see CLINICAL PHARMACOLOGY) and therefore monitoring of patients after overdose with eletriptan should continue for at least 20 hours, or longer should symptoms or signs persist.

There is no specific antidote to eletriptan. In cases of severe intoxication, intensive care procedures are recommended, including establishing and maintaining a patent airway, ensuring adequate oxygenation and ventilation, and monitoring and support of the cardiovascular system.

It is unknown what effect hemodialysis or peritoneal dialysis has on the serum concentration of eletriptan.

CONTRAINDICATIONS

RELPAX Tablets should not be given to patients with ischemic heart disease (e.g., angina pectoris, history of myocardial infarction, or documented silent ischemia) or to patients who have symptoms, or findings consistent with ischemic heart disease, coronary artery vasospasm, including Prinzmetal's variant angina, or other significant underlying cardiovascular disease (see WARNINGS).

RELPAX Tablets should not be given to patients with cerebrovascular syndromes including (but not limited to) strokes of any type as well as transient ischemic attacks (see WARNINGS).

RELPAX Tablets should not be given to patients with peripheral vascular disease including (but not limited to) ischemic bowel disease (see WARNINGS).

Because RELPAX Tablets may increase blood pressure, it should not be given to patients with uncontrolled hypertension (see WARNINGS).

RELPAX Tablets should not be administered to patients with hemiplegic or basilar migraine.

RELPAX Tablets should not be used within 24 hours of treatment with another 5-HT₁ agonist, an ergotamine-containing or ergot-type medication such as dihydroergotamine (DHE) or methysergide.

RELPAX Tablets should not be used in patients with known hypersensitivity to eletriptan or any of its inactive ingredients.

RELPAX Tablets should not be given to patients with severe hepatic impairment.