Pizotifen, also known as pizotyline and sold under the brand names Sandomigran and Mosegor among others, is an antimigraine agent of the tricyclic group which is used primarily as a prophylaxis to reduce the frequency of recurrent migraine headaches.
Medical uses
Migraine headaches
The main medical use for pizotifen is for the prevention of
migraine and
cluster headache. Pizotifen is one of a range of medications used for this purpose, other options include
propranolol,
topiramate,
valproic acid,
cyproheptadine and
amitriptyline. While pizotifen is effective in adults,
evidence of efficacy in children is limited,
and its use is limited by side effects, principally drowsiness and weight gain, and it is usually not the first choice medicine for preventing migraines, instead being used as an alternative when other drugs have failed to be effective.
It is not effective in relieving migraine attacks once in progress.
Other uses
Pizotifen has also been reported as highly effective in a severe case of
erythromelalgia, a rare neurovascular disease that is sometimes refractory to the other drugs named above.
Other applications for which pizotifen may be used include as an antidepressant, or for the treatment of anxiety or social phobia.
Pizotifen might be useful as a trip killer in blocking the effects of serotonergic psychedelics like psilocybin.
Contraindications
Caution is required in patients having closed angle
glaucoma and in patients with a predisposition to urinary retention as the medication exhibits a relatively small anticholinergic effect. Dose adjustment is required in people who have chronic kidney disease. Liver injury has also been reported. Pizotifen treatment should be discontinued if there is any clinical evidence of liver dysfunction during treatment. Caution is advised in patients having a history of
epilepsy.
Withdrawal symptoms like depression, tremor, nausea, anxiety, malaise, dizziness, sleep disorder and weight decrease have been reported following abrupt cessation of pizotifen.
Pizotifen is contraindicated in patients who suffer from hypersensitivity to any of its components or have gastric outlet obstruction, angle-closure glaucoma, and difficulty urinating.
Adverse effects
Side effects include
sedation,
dry mouth, drowsiness, increased appetite and weight gain.
[Crowder D, Maclay WP. Pizotifen once daily in the prophylaxis of migraine: results of a multi-centre general practice study. Current Medical Research and Opinion. 1984;9(4):280-5.] Occasionally it may cause nausea, headaches, or dizziness. In rare cases, anxiety, aggression and depression may also occur.
Pharmacology
Pharmacodynamics
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Note: The smaller the value, the more avidly the compound binds to or activates the site. Refs: |
Pizotifen is a serotonin antagonist acting mainly at the 5-HT2A, 5-HT2B, and 5-HT2C receptors. It also has some activity as an antihistamine as well as some anticholinergic activity.
Pizotifen is able to dose dependence and fully antagonize the discriminative stimulus effects of the serotonin–norepinephrine–dopamine releasing agent and serotonin 5-HT2 receptor agonist MDMA in rodent drug discrimination tests.
The antimigraine activity of pizotifen might be specifically due to serotonin 5-HT2B receptor blockade.
Chemistry
Pizotifen is a tricyclic compound and is specifically a benzocycloheptene.
Close analogues of pizotifen include ketotifen and cyproheptadine, among others.
History
Pizotifen was first described in the literature by 1964.
Society and culture
Names
Pizotifen is the
generic term of the drug and its and , while
pizotyline is its .
Brand names of pizotifen include Sandomigran, Mosegor, and Litec, among others.
Availability
Pizotifen is available widely throughout the world, including in
Europe.
External links
