What is Periactin (cyproheptadine)?

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From the Guidelines

Periactin (cyproheptadine) is a first-generation antihistamine medication that blocks H1 histamine receptors and also has antiserotonergic and anticholinergic properties, primarily used to treat allergic reactions and sometimes prescribed off-label as an appetite stimulant.

Key Points

  • Periactin is used to treat allergic reactions, including hay fever, allergic skin reactions, and itching 1.
  • It is also used as an appetite stimulant, particularly in underweight children or adults experiencing appetite loss due to medical conditions or treatments 1.
  • The typical dosage for adults is 4 mg taken three to four times daily, while children's dosages are based on weight and age.
  • Common side effects include drowsiness, dry mouth, dizziness, and increased appetite.
  • Patients should be aware that Periactin may cause sedation, so activities requiring mental alertness should be avoided until the response to the medication is known.
  • Periactin should not be taken with alcohol or other central nervous system depressants, and patients with certain conditions like glaucoma, urinary retention, or certain cardiovascular disorders should use it with caution 1.

Usage and Dosage

  • The medication works by preventing histamine from binding to H1 receptors in the body, thereby reducing allergic symptoms, while its effect on serotonin and certain brain pathways explains its appetite-stimulating properties.
  • 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 1.
  • The pediatric dosage is usually 0.25 mg/kg per day.

Important Considerations

  • Periactin may be used to treat gastrointestinal symptoms in patients with mast cell activation syndrome (MCAS) or systemic mastocytosis (SM) 1.
  • Cognitive decline has been reported for H1 blockers that have anticholinergic effects, especially in the elderly population 1.

From the FDA Drug Label

Cyproheptadine is a serotonin and histamine antagonist with anticholinergic and sedative effects. Cyproheptadine hydrochloride is an antihistaminic and antiserotonergic agent.

Periactin (cyproheptadine) is an antihistaminic and antiserotonergic agent, which acts as a serotonin and histamine antagonist with anticholinergic and sedative effects 2, 2.

From the Research

What is Periactin (Cyproheptadine)?

Periactin, also known as cyproheptadine, is a first-generation antihistamine that is available in over-the-counter cold medications and is used to treat allergic-type symptoms 3.

Uses of Cyproheptadine

Some of the uses of cyproheptadine include:

  • Appetite stimulation: Cyproheptadine has been shown to be an effective appetite stimulant in patients with cystic fibrosis 4 and in children with cancer/treatment-related cachexia 5.
  • Treatment of chronic urticaria: Cyproheptadine has been compared with other antihistamines in the treatment of chronic urticaria and has been shown to be effective 6.
  • Weight gain: Cyproheptadine has been shown to promote weight gain in thin but otherwise normal volunteers 7 and in patients with cancer/treatment-related cachexia 5.

Side Effects of Cyproheptadine

Some of the side effects of cyproheptadine include:

  • Drowsiness: This is a common side effect of cyproheptadine, especially at higher doses 4, 5, 7.
  • Sedation: Cyproheptadine has been shown to have a sedative effect, especially when compared with other antihistamines 6.
  • Increased appetite: Cyproheptadine has been shown to increase appetite and food intake in patients 4, 5, 7.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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