Periactin (cyproheptadine hydrochloride) is a first-generation antihistamine and serotonin antagonist with established clinical utility in managing allergic conditions and promoting weight gain. As a potent H1-receptor blocker, it effectively mitigates histamine-mediated symptoms while its additional mechanisms support appetite enhancement in underweight patients. This medication is particularly valuable in pediatric and geriatric populations where allergic reactions or poor nutritional intake present significant health challenges. Available by prescription, Periactin offers a dual therapeutic approach for specific clinical scenarios requiring both antihistaminic and orexigenic effects.

Features

• Contains cyproheptadine hydrochloride as active ingredient
• Available in 4mg tablets and 2mg/5mL syrup formulations
• Demonstrates potent antihistaminic and antiserotonergic properties
• Exhibits anticholinergic and sedative effects
• Typically administered two to three times daily
• Compatible with multiple therapeutic regimens when appropriately monitored

Benefits

• Effectively reduces symptoms of allergic reactions including urticaria, rhinitis, and conjunctivitis
• Promotes measurable weight gain in patients with appetite deficiencies or cachexia
• Provides relief from pruritus associated with various dermatological conditions
• May help manage serotonin syndrome in emergency situations
• Offers cost-effective therapy compared to newer alternatives
• Demonstrates rapid onset of action within 20-30 minutes of administration

Common use

Periactin is primarily indicated for the management of allergic conditions unresponsive to conventional antihistamines, including perennial and seasonal allergic rhinitis, vasomotor rhinitis, allergic conjunctivitis, mild urticaria, and angioedema. Its secondary application involves appetite stimulation in underweight patients, particularly children with failure to thrive, adults with cachexia related to chronic diseases, and individuals experiencing medication-induced appetite suppression. Off-label uses include management of serotonin syndrome, migraine prophylaxis, and treatment of night sweats associated with various conditions.

Dosage and direction

For allergic conditions in adults: 4-20 mg daily in divided doses, not to exceed 0.5 mg/kg/day. Maximum daily dose: 32 mg. For children 2-6 years: 2 mg two to three times daily, maximum 12 mg/day. For children 7-14 years: 4 mg two to three times daily, maximum 16 mg/day. For appetite stimulation: Typically 2-4 mg three times daily before meals. Geriatric patients may require lower initial doses due to increased sensitivity. Administration with food may minimize gastrointestinal discomfort. Dosage adjustments necessary for hepatic impairment.

Precautions

Exercise caution in patients with narrow-angle glaucoma, stenosing peptic ulcer, pyloroduodenal obstruction, bladder neck obstruction, prostatic hypertrophy, or elderly males with potential prostatic hypertrophy. Use cautiously in patients with hypertension, cardiovascular disease, hyperthyroidism, or bronchial asthma. May cause drowsiness; patients should avoid driving or operating machinery until response is determined. Alcohol and other CNS depressants may potentiate sedative effects. Discontinue at least 4 days before skin testing to avoid false negative results.

Contraindications

Hypersensitivity to cyproheptadine or other antihistamines of similar chemical structure. Neonates and premature infants due to increased risk of anticholinergic effects. Patients receiving monoamine oxidase inhibitors (concurrent or within 14 days). Acute asthma attacks. Breastfeeding mothers due to secretion in milk. Patients with angle-closure glaucoma. Those with gastrointestinal obstruction or urinary retention.

Possible side effect

Common: Drowsiness (affects 20-50% of patients), dizziness, dry mouth/nose/throat, nausea, headache, appetite increase, weight gain. Less common: Restlessness, excitation, nervousness, insomnia, euphoria, blurred vision, diplopia, vertigo, tinnitus, hypotension, palpitations, tachycardia, anorexia, constipation, diarrhea, urinary retention, early menses, thickening of bronchial secretions. Rare: Blood dyscrasias, hepatitis, seizures, anaphylaxis, photosensitivity.

Drug interaction

MAO inhibitors: May prolong and intensify anticholinergic effects. CNS depressants: Enhanced sedative effects with alcohol, barbiturates, tranquilizers, hypnotics. Anticholinergic drugs: Additive effects with atropine, tricyclic antidepressants. Serotonergic drugs: May reduce effectiveness of SSRIs, SNRIs, triptans. CYP3A4 inhibitors: May increase cyproheptadine levels. Epinephrine: Reverse pressor effect. Beta-blockers: Potential enhanced hypotensive effects.

Missed dose

If a dose is missed, take it as soon as remembered unless it is nearly time for the next scheduled dose. Do not double the dose to make up for a missed dose. If multiple doses are missed, contact healthcare provider for guidance. Maintain regular dosing schedule to ensure consistent therapeutic effect, particularly for appetite stimulation where timing relative to meals is important.

Overdose

Symptoms may include CNS depression (sedation, coma, respiratory depression) or CNS stimulation (insomnia, hallucinations, convulsions) especially in children. Anticholinergic effects: Dry mouth, fixed dilated pupils, flushing, gastrointestinal symptoms, urinary retention. Cardiovascular effects: Tachycardia, hypotension, hypertension, cardiac arrhythmias. Treatment: Gastric lavage if recent ingestion, activated charcoal, supportive measures. Physostigmine may be considered for severe central anticholinergic effects. Dialysis not effective.

Storage

Store at controlled room temperature (20-25°C or 68-77°F). Protect from light and moisture. Keep bottle tightly closed. Do not freeze syrup formulation. Keep out of reach of children and pets. Do not use after expiration date printed on packaging. Discard any unused medication properly according to local regulations, preferably through medication take-back programs.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Periactin is a prescription medication requiring professional medical supervision. Individual response may vary. Always consult with a qualified healthcare provider before starting, changing, or stopping any medication. The complete prescribing information should be reviewed before administration. Not all possible uses, precautions, side effects, or interactions are listed here.

Reviews

Clinical studies demonstrate Periactin’s efficacy in allergic conditions with 70-80% of patients experiencing significant symptom relief. In appetite stimulation studies, weight gain of 1-2 kg per month has been observed in appropriately selected patients. Many clinicians report particular success in pediatric patients with failure to thrive, noting improved growth parameters within 2-3 months of therapy. Some patients report satisfactory allergy control with fewer doses than required with newer antihistamines. The sedative effects are noted as limiting by some adult patients, while others find the nighttime dosing beneficial for sleep. Cost-effectiveness is frequently cited as a significant advantage over newer alternatives.