(British Approved Name, rINN)
Drug Nomenclature
Synonyms: BC-105; Pitsotifeeni; Pizotifen; Pizotifeno; PizotifenumPharmacopoeias. In China.
Pizotifen Malate
(British Approved Name Modified, rINNM)
Drug Nomenclature
Pharmacopoeias. In British.
British Pharmacopoeia 2008 (Pizotifen Malate). A white or slightly yellowish-white, odourless or almost odourless, crystalline powder. Very slightly soluble in water; slightly soluble in alcohol and in chloroform; sparingly soluble in methyl alcohol. Protect from light.
Adverse Effects and Precautions
As for the sedating antihistamines in general.
Increased appetite and weight gain may occur with pizotifen. Drowsiness may be troublesome.
Incidence of adverse effects
Adverse effects were noted in 22 of 47 patients with severe migraine given pizotifen 1 to 2 mg daily. These reactions included weight increase (15), muscle pain or cramps (3), heavy or restless legs (3), fluid retention (3), drowsiness (2), more frequent milder headaches (2), facial flushing (1), reduced libido (1), exacerbation of epilepsy (1), and dreaming (2). Adverse effects necessitating withdrawal occurred in 11 patients.
Interactions
As for the sedating antihistamines in general.
Antihypertensives
After a report of loss of blood pressure control when treatment with pizotifen was started in a patient receiving debrisoquine the manufacturer suggested that since pizotifen had a similar chemical structure to the tricyclic antidepres-sants it might antagonise the actions of adrenergic neurone blockers in a similar manner.
Pharmacokinetics
Pizotifen is well absorbed from the gastrointestinal tract, peak plasma concentrations occurring about 5 hours after a single oral dose. Over 90% is bound to plasma proteins. Pizotifen undergoes extensive metabolism. Over half of a dose is excreted in the urine, chiefly as metabolites; a significant proportion is excreted in the faeces. The primary metabolite of pizotifen (N-glucuronide conjugate) has a long elimination half-life of about 23 hours.
Distribution into milk has been found in animal studies.
Uses and Administration
Pizotifen is a sedating antihistamine that has strong serotonin antagonist and weak antimuscarinic properties. It also antagonises the action of tryptamine. Pizotifen is used, usually as the malate, for the prophylaxis of migraine and for the prevention of headache attacks during cluster periods. It is not effective in treating an acute attack. Doses of pizotifen malate are expressed in terms of the base; pizotifen malate 1.45 mg is equivalent to about 1 mg of pizotifen. The usual adult oral dose is 1.5 mg daily either in three divided doses or as a single dose at night; children aged over 2 years may also be given up to 1.5 mg daily, although the maximum single dose (at night) should not exceed 1 mg.
Gradual increase from an initial dose of 500 micrograms may help to avoid undue drowsiness. Doses in adults may vary from 500 micrograms up to a maximum of 4.5 mg daily; not more than 3 mg should be given as a single dose. Pizotifen hydrochloride has also been used in the management of migraine.
Abdominal migraine
Abdominal migraine is a recurrent disorder seen mainly in children and characterised by episodic mid-line abdominal pain lasting for up to 72 hours. The pain is severe enough to disrupt normal activities and may be associated with pallor, anorexia, nausea, and vomiting. Sleep, and sometimes vomiting, terminate the attack.
Pizotifen was found to be effective for the prophylaxis of abdominal pain in children with abdominal migraine. Prophylactic treatment with propranolol or cyproheptadine may also be of benefit.
Migraine and cluster headache
Pizotifen has been widely used for the prophylaxis of migraine but evidence for its efficacy is limited. It has also been tried in the management of cluster headache to prevent headache attacks during a cluster period.
Preparations
British Pharmacopoeia 2008: Pizotifen Tablets.
Single-ingredient Preparations
The symbol ¤ denotes a preparation which is discontinued or no longer actively marketed.
Argentina: Sandomigran;
Australia: Sandomigran;
Austria: Sandomigran¤;
Belgium: Mosegor¤; Sandomigran;
Brazil: Sandomigran;
Canada: Sandomigran¤;
Czech Republic: Sandomigran;
Denmark: Sandomigrin;
France: Sanmigran;
Germany: Mosegor; Sandomigran¤;
Greece: Mosegor¤;
Hong Kong: Sandomigran;
Hungary: Sandomigran;
Ireland: Sanomigran;
Israel: Sandomigran¤;
Italy: Sandomigran;
Malaysia: Sandomigran;
Netherlands: Sandomigran;
Norway: Sandomigrin¤;
New Zealand: Sandomigran;
South Africa: Sandomigran;
Spain: Mosegor; Sandomigran;
Sweden: Sandomigrin;
Switzerland: Mosegor; Sandomigran¤;
Thailand: Anorsia; Mosegor; Moselar; Pizomed; Zofen;
United Kingdom: Sanomigran;
Venezuela: Sandomiran
Jennifer is a clinical pharmacologist. She helps doctors of all medical specialties choose medications. Jennifer consults about drug dosage, interactions, and side effects.