(British Approved Name, US Adopted Name, rINN)
Drug Nomenclature
International Nonproprietary Names (INNs) in main languages (French, Latin, Russian, and Spanish):
Synonyms: 311C90; Tsolmitriptaani; Zolmitriptán; Zolmitriptan; ZolmitriptanumAdverse Effects and Precautions
As for Sumatriptan.
Zolmitriptan should also be avoided in patients with Wolff-Parkinson-White syndrome or arrhythmias associated with accessory cardiac conduction pathways. It should be given with caution in patients with moderate to severe hepatic impairment.
Ischaemia
A spinal cord lesion related to the use of zolmitriptan has been reported in a 50-year-old woman; clinical features suggested that the lesion was an ischaemic infarct.
Medication-overuse headache
For a report of an association between zolmitriptan and medication-overuse headache, see under Adverse Effects of Sumatriptan.
Interactions
As for Sumatriptan.
It is recommended that the maximum dose of zolmitriptan in 24 hours should be reduced in patients receiving cimetidine (see Uses and Administration, below). A similar reduction in zolmitriptan dosage is anticipated if it is given with drugs, such as fluvoxam-ine and ciprofloxacin, that inhibit the cytochrome P450 isoenzyme CYP1A2. Opinion varies on the use of zolmitriptan with inhibitors of monoamine oxidase type A such as moclobemide. In the UK licensed product information recommends that the maximum dose of zolmitriptan should be reduced when used with inhibitors of monoamine oxidase type A (see Uses and Administration, below), whereas in the USA such combinations are contra-indicated.
Beta blockers
Propranolol increased plasma-zolmitriptan concentrations in a study in 12 healthy subjects, but the changes were not thought to be clinically important enough to warrant dosage adjustment during concomitant use.
Pharmacokinetics
The absolute bioavailability of zolmitriptan after oral and intranasal doses is about 40%, and peak plasma concentrations are achieved in about 1.5 to 3 hours after oral doses, depending on the formulation, and in about 3 hours with the intranasal spray. Plasma protein binding is about 25%. Zolmitriptan undergoes hepatic metabolism, principally to the indole acetic acid, and also the N-oxide and N-desmethyl analogues. The N-desmethyl metabolite (183C91) was more active than the parent compound in animal studies, and would be expected to contribute to the therapeutic effect of zolmitriptan.
The primary metabolism of zolmitriptan is mediated mainly by the cytochrome P450 isoenzyme CYP1A2 while monoamine oxidase type A is responsible for further metabolism of the N-desmethyl metabolite. Over 60% of a dose is excreted in the urine, mainly as the indole acetic acid, and about 30% appears in the faeces, mainly as unchanged drug. The elimination half-life is 2.5 to 3 hours, and is prolonged in patients with liver disease. Distribution into milk has been found in studies in rats.
Uses and Administration
Zolmitriptan is a selective serotonin (5-HT1) agonist with actions and uses similar to those of sumatriptan. It is used for the acute treatment of migraine attacks. Zolmitriptan should not be used for prophylaxis.
The recommended dose in the UK is 2.5 mg orally. A clinical response can be expected within 1 hour. If symptoms persist or return within 24 hours, a second dose may be taken not less than 2 hours after the first dose. If a patient does not achieve satisfactory relief with a dose of 2.5 mg, subsequent attacks may be treated with doses of 5 mg. The maximum dose of zolmitriptan in 24 hours is 10 mg. Recommended doses in the USA are somewhat lower; the dose is 1.25 or 2.5 mg with a maximum dose of 10 mg in 24 hours. When used intranasally a clinical response can be expected in 15 minutes. The usual dose is 5 mg as a single dose into one nostril. If symptoms persist or return within 24 hours, a second dose may be given after at least 2 hours, up to a maximum of 10 mg daily.
Dose reductions are recommended in patients taking certain other drugs. The maximum dose of zolmitriptan in 24 hours should be 5 mg in those receiving cimetidine or an inhibitor of monoamine oxidase type A (although use with inhibitors of monoamine oxidase type A is contra-indicated in the USA). A similar reduction is also recommended in those taking drugs, such as fluvoxamine and ciprofloxacin, that inhibit the cytochrome P450 isoenzyme CYP1A2. For dosage in hepatic or renal impairment see below.
Administration in hepatic impairment
A study has indicated that while there is no need to reduce the size of the initial dose of zolmitriptan in patients with moderate or severe hepatic impairment, accumulation may occur with repeated doses in patients with severe impairment and their total daily dosage should be reduced.
A maximum oral dose of 5 mg in 24 hours is recommended by licensed product information in the UK in patients with moderate to severe impairment. A dose of less than 2.5 mg is recommended in the USA.
Administration in renal impairment
Although renal clearance of zolmitriptan and its metabolites was reduced in patients with moderate to severe impairment, the resulting effect was unlikely to be of clinical importance and adjustment of zolmitriptan dosage in patients with renal impairment was considered unnecessary.
Migraine and cluster headache
For comparison of the relative benefits of different triptans in migraine, see under Sumatriptan.
Single-ingredient Preparations
Argentina: Zomigon;
Australia: Zomig;
Austria: Zomig;
Belgium: Zomig;
Brazil: Zomig;
Canada: Zomig;
Czech Republic: Zomig;
Denmark: Zomig;
Finland: Zomig;
France: Zomig; Zomigoro;
Germany: AscoTop;
Greece: Zomigon;
Hong Kong: Zomig;
Hungary: Zomig;
Ireland: Zomig;
Israel: Zomig;
Italy: Zomig;
Mexico: Zomig;
Netherlands: Zomig;
Norway: Zomig;
Portugal: Zomig;
Russia: Zomig (Зомиг);
South Africa: Zomig;
Singapore: Zomig;
Spain: Flezol; Zomig;
Sweden: Zomig;
Switzerland: Zomig;
Thailand: Zomig;
United Kingdom: Zomig;
United States: Zomig;
Venezuela: Zomig
Jennifer is a clinical pharmacologist. She helps doctors of all medical specialties choose medications. Jennifer consults about drug dosage, interactions, and side effects.