What are the uses of Cyproheptadine (Periactin)?

From the Guidelines

Cyproheptadine is primarily used as an antihistamine to treat allergic reactions, including hay fever, allergic rhinitis, and skin reactions like hives and itching, as well as an appetite stimulant for patients with anorexia, cancer-related weight loss, or failure to thrive in children, and to manage serotonin syndrome. The medication works by blocking histamine H1 receptors and serotonin receptors, which explains its diverse effects. Common side effects include drowsiness, dry mouth, and increased appetite. Patients should be aware that it may take several days to see full effects, particularly when used for appetite stimulation, and the medication should not be abruptly discontinued after long-term use. Some key uses of cyproheptadine include:

• Treating allergic reactions, such as hay fever, allergic rhinitis, and skin reactions like hives and itching, typically at doses of 2-4 mg three to four times daily for adults and 0.25 mg/kg/day divided into 2-3 doses for children 1.
• Stimulating appetite in patients with anorexia, cancer-related weight loss, or failure to thrive in children, with a study showing a clinically relevant effect size for weight/age (z score) and body mass index for age (z score) 1.
• Managing serotonin syndrome, a potentially life-threatening condition caused by excess serotonin, at doses of 8-32 mg daily divided into multiple doses, with cyproheptadine being the most commonly used serotonin2A antagonist 1. It's sometimes used off-label for migraine prevention, nightmares, and certain neuroendocrine disorders. The dosage of cyproheptadine is usually 12 to 24 mg over 24 hours, typically starting with 12 mg, followed by 2 mg every 2 hours for continuing symptoms, and a maintenance dose of 8 mg every 6 hours, given orally, with no parenteral form available, but tablets can be crushed and administered via a nasogastric tube 1.

From the FDA Drug Label

CLINICAL PHARMACOLOGY Cyproheptadine is a serotonin and histamine antagonist with anticholinergic and sedative effects. The uses of Cyproheptadine (Periactin) are not explicitly stated in the provided drug label. No conclusion can be drawn about the specific uses of Cyproheptadine (Periactin) from the given information 2.

From the Research

Uses of Cyproheptadine (Periactin)

• Cyproheptadine is used as a serotonin antagonist in the treatment of serotonin syndrome, a life-threatening condition caused by serotonergic agents 3, 4, 5, 6.
• It is administered to patients with serotonin syndrome to provide symptomatic relief and has been shown to produce rapid reversal of mydriasis within one hour of the initial dose 6.
• Cyproheptadine can be used as a prophylactic treatment to prevent serotonin syndrome in patients taking multiple serotonergic agents, such as those requiring linezolid therapy 7.
• The medication has been used to treat patients with severe symptoms of serotonin syndrome, including hyperreflexia, clonus, tachycardia, and tremor 3, 5.
• Cyproheptadine has been administered in various dosing schedules, including a loading dose of 12 mg followed by 2 mg every 2 h for at least 24 h in ICU patients, and 4 mg three times a day in ward patients 3.

Administration and Dosage

• The dosing schedule for cyproheptadine in the treatment of serotonin syndrome is not uniform in the literature 3, 4.
• Cyproheptadine has been administered orally in doses ranging from 4-8 mg 5, 6.
• The total doses of cyproheptadine and the length of treatment have differed between patients 3.

Efficacy and Safety

• Cyproheptadine has been shown to be effective in treating serotonin syndrome, with all patients in one study showing at least some response to the medication within 24 h 3.
• The medication has been well-tolerated, with no adverse outcomes reported in some studies 5.
• However, the benefits and indications for cyproheptadine in the management of serotonin syndrome are uncertain and questionable, and future recommendations on its use should be based on diagnostic criteria, severity of symptoms, and management in conjunction with other supportive measures 4.