Trade names Sandomigran Molar mass 295.443 g/mol Protein binding 91% | Pregnancycategory AU: B1 ATC code N02CX01 (WHO) Bioavailability 78% | |
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AHFS/Drugs.com International Drug Names Legal status AU: S4 (Prescription only)CA: ℞-onlyUK: POM (Prescription only) | ||
Pizotifen (INN) or pizotyline (USAN), trade name Sandomigran, is a benzocycloheptene-based drug used as a medicine, primarily as a preventative to reduce the frequency of recurrent migraine headaches.
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Uses
The main medical use for pizotifen is for the prevention of vascular headache including migraine and cluster headache. Pizotifen is one of a range of medications used for this purpose, other options include propranolol, topiramate, valproic acid and amitriptyline. While pizotifen is reasonably effective, 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. 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. Animal studies also suggest that pizotyline could be used in the treatment of serotonin syndrome or MDMA overdose in a similar manner to the closely related antihistamine/antiserotonin drug cyproheptadine.
Adverse effects
Side effects include sedation, dry mouth, drowsiness, increased appetite and weight gain. Occasionally it may cause nausea, headaches, or dizziness. In rare cases, anxiety, aggression and depression may also occur.
Contraindications
Caution is required in patients having closed angle glaucoma and in patients with a predisposition to urinary retention as the drug exhibits a relatively small anticholinergic effect. Dose adjustment is required in patients having renal insufficiency. Hepatic injury has also been reported. Pizotifen treatment should be discontinued if there is any clinical evidence of hepatic 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, also Pizotifen is contraindicated in gastric outlet obstruction, pregnancy, angle-closure glaucoma and difficulty urinating.
Mechanism of Action
Pizotifen is a serotonin antagonist acting mainly at the 5-HT2A and 5HT2C receptors. It also has some activity as an antihistamine as well as some anticholinergic activity.