RIZATRIPTAN BENZOATE
(ri-za-trip'tan ben'zo-ate)
Maxalt, Maxalt-MLT
Classifications: autonomic nervous system agent; adrenergic antagonist (sympatholytic); serotonin 5-htib/id receptor agonist
Prototype: Sumatriptan
Pregnancy Category: C

Availability

5 mg, 10 mg tablets; 5 mg, 10 mg disintegrating tablets

Actions

Selective (5-HT1B/1D) receptor agonist. The agonist effects at 5-HT1B/1D reverse the vasodilation of cranial blood vessels associated with a migraine.

Therapeutic Effects

Activation of the 5-HT1B/1D receptors reduces the pain pathways associated with the migraine headache as well as reversing vasodilation of cranial blood vessels.

Uses

Acute migraine headaches with or without aura.

Contraindications

Hypersensitivity to rizatriptan; CAD; Prinzmetal's angina (potential for vasospasm); risk factors for CAD such as hypertension, hypercholesterolemia, obesity, diabetes, smoking, and strong family history; concurrent administration with ergotamine drugs or sumatriptan; concurrent administration with MAOIs; basilar or hemiplegic migraine.

Cautious Use

Hypersensitivity to sumatriptan; renal or hepatic impairment; pregnancy (category C), lactation; hypertension; asthmatic patients. Safety and effectiveness in patients <18 y are not established.

Route & Dosage

Acute Migraine
Adult: PO 5–10 mg, may repeat in 2 h if necessary (max: 30 mg/24 h); 5 mg with concurrent propranolol (max: 15 mg/24 h)

Administration

Oral

Adverse Effects (1%)

Body as a Whole: Asthenia, fatigue, pain, pressure sensation, paresthesias, throat pressure, warm/cold sensations. CNS: Somnolence, dizziness, headache, hypesthesia, decreased mental acuity, euphoria, tremor. CV: Coronary artery vasospasm, transient myocardial ischemia, MI, ventricular tachycardia, ventricular fibrillation, chest pain/tightness/heaviness, palpitations. GI: Dry mouth, nausea, vomiting, diarrhea. Respiratory: Dyspnea. Skin: Flushing. Endocrine: Hot flashes.

Interactions

Drug: Propranolol may increase concentrations of rizatriptan, use smaller rizatriptan doses; dihydroergotamine, methysergide, other 5-ht 1 agonists may cause prolonged vasospastic reactions; ssris have rarely caused weakness, hyperreflexia, and incoordination; maois should not be used with 5-HT1 agonists. Herbal: St. John's wort may increase triptan toxicity.

Pharmacokinetics

Absorption: 45% of oral dose reaches systemic circulation. Peak: 1–1.5 h for oral tabs; 1.6–2.5 h for orally disintegrating tablets. Metabolism: Metabolized via oxidative deamination by monoamine oxidase A. Elimination: Excreted primarily in urine (82%). Half-Life: 2–3 h.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education


Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug