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trademark for preparations of cyproheptadine hydrochloride, an antihistamine used for relief of allergy and itching.

cyproheptadine hydrochloride

Periactin (UK), PMS-Cyproheptadine (CA)

Pharmacologic class: Piperidine (nonselective)

Therapeutic class: Antihistamine

Pregnancy risk category B


Antagonizes effects of histamine at histamine1-receptor sites, preventing histamine-mediated responses. Also blocks effects of serotonin, causing increased appetite.


Syrup: 2 mg/5 ml

Tablets: 4 mg

Indications and dosages

Allergy symptoms caused by histamine release (including seasonal and perennial allergic rhinitis); chronic urticaria; angioedema; dermographism; cold urticaria; adjunctive therapy for anaphylactic reactions

Adults: Initially, 4 mg P.O. q 8 hours. Maintenance dosage is 4 to 20 mg/day in three divided doses, to a maximum dosage of 0.5 mg/kg/day.

Children ages 7 to 14: 2 to 4 mg P.O. q 12 hours. Don't exceed 16 mg/day.

Children ages 2 to 6: 2 mg P.O. q 12 hours. Don't exceed 12 mg/day.

Off-label uses

• Vascular cluster headaches
• Anorexia nervosa
• Cushing's syndrome


• Hypersensitivity to drug
• Alcohol intolerance (syrup only)
• Bladder neck obstruction
• Angle-closure glaucoma
• Ulcer disease
• Symptomatic prostatic hypertrophy
• MAO inhibitor use within past 14 days


Use cautiously in:
• hepatic impairment
• elderly patients
• pregnant patients (safety not established)
• breastfeeding patients.


• Give with food or milk to decrease GI upset.

Adverse reactions

CNS: drowsiness, dizziness, excitation (especially in children), fatigue, sedation, hallucinations, disorientation, tremor

CV: palpitations, hypotension, arrhythmias

EENT: blurred vision, nasal dryness and congestion, dry throat

GI: constipation, dry mouth

GU: urinary retention, urinary frequency, ejaculatory inhibition, early menses

Respiratory: thickened bronchial secretions

Skin: rash, photosensitivity

Other: weight gain


Drug-drug.CNS depressants (including opioid analgesics, sedative-hypnotics): increased CNS depression

MAO inhibitors: intensified, prolonged anticholinergic effects

Drug-diagnostic tests.Allergy skin tests: false-negative reactions

Drug-behaviors.Alcohol use: increased CNS depression

Patient monitoring

• Monitor patient for excessive anti-cholinergic effects.
• Assess for excessive CNS depression.
• Discontinue drug 4 days before diagnostic skin testing.

Patient teaching

• Advise patient to take drug with food to minimize GI upset.
• Caution patient not to use other CNS depressants, sleep aids, or alcohol during therapy.
• Instruct patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.


A trademark for the drug cyproheptadine hydrochloride.


a trademark for an antihistamine and antipruritic used to treat rash and other symptoms of allergies (cyproheptadine hydrochloride).
A substance that had transient currency with some atheletes as it was believed to stimulate the appetite


A brand name for CYPROHEPTADINE.
References in periodicals archive ?
I continued to use moisturizing creams and lotions, Opticrom eye drops, OTC eye drops, hydrocortisone creams, Periactin, Tagamet and antihistamines, and of course ZOLOFT
Her doctor also prescribed Periactin, thinking migraines could be causing her behavior.
Antihistamines (Combination, cold/hay fever products with decongestants) -- Chlor-trimeton (Ornade, Isochlor), Dimetane (Dimetapp), Benadryl, Tavist, Ambodryl, Clistin, Decapryn, Polaramine, Forhistal, Actidil (Actifed), PBZ, Histadyl, Tacaryl, Phenergan, Temaril, Atarax/Vistaril, Optimine, Periactin, Seldane, Hismanal