• Allergies

Cyproheptadine Generic Name & Formulations

General Description

Cyproheptadine HCl 4mg; scored tabs.

Pharmacological Class


How Supplied

Contact supplier.

Mechanism of Action

Cyproheptadine is a serotonin and histamine antagonist with anticholinergic and sedative effects. Antiserotonin and antihistamine drugs appear to compete with serotonin and histamine, respectively, for receptor sites.

Cyproheptadine Indications


Allergic and vasomotor rhinitis, conjunctivitis, urticaria, angioedema, reactions to blood. Adjunct in anaphylaxis. Cold urticaria. Dermatographism.

Cyproheptadine Dosage and Administration


≥14yrs: initially 4mg 3 times daily; usual range 12–16mg/day; max 0.5mg/kg per day.


<2yrs: not established. 2–6yrs: 2mg 2–3 times per day; max 12mg daily. 7–14yrs: 4mg 2–3 times per day; max 16mg daily.

Cyproheptadine Contraindications


MAOIs. Peptic ulcer. Glaucoma. Prostatic hypertrophy. Bladder neck obstruction. Pyloroduodenal obstruction. Elderly. Debilitated. Newborn or premature infants. Nursing mothers.

Cyproheptadine Boxed Warnings

Not Applicable

Cyproheptadine Warnings/Precautions


Hyperthyroidism. Cardiovascular disease. Hypertension. Increased intraocular pressure. History of asthma. Pregnancy (Cat.B).


Pediatric Patients

  • Overdosage of antihistamines, especially in infants and young children, may cause hallucinations, CNS depression, convulsions, respiratory and cardiac arrest, and death.
  • Antihistamines may diminish mental alertness; however, in young children, they may occasionally cause excitation.

CNS Depressants

  • Antihistamines may have additive effects with alcohol and other CNS depressants (eg, hypnotics, sedatives, tranquilizers, antianxiety agents).

Activities Requiring Mental Alertness

  • Patients should be warned about engaging in activities requiring mental alertness and motor coordination (eg, driving a car or operating machinery).
  • Antihistamines are more likely to cause dizziness, sedation, and hypotension in elderly patients.

Pregnancy Considerations

Assessment of 2 studies in pregnant women have not shown that cyproheptadine increases the risk of abnormalities when administered during the 1st, 2nd, and 3rd trimesters of pregnancy. No teratogenic effects were observed in any of the newborns.

Although the studies in humans cannot rule out the possibility of harm, cyproheptadine should be used during pregnancy only if clearly needed.

Nursing Mother Considerations

It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, and due to the potential for serious adverse reactions in nursing infants from cyproheptadine, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Considerations

Safety and effectiveness in pediatric patients <2 years of age have not been established.

Geriatric Considerations

In general, dose selection for an elderly patient should be cautious. Start at the lower end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Cyproheptadine Pharmacokinetics


Renal, fecal.

Cyproheptadine Interactions


See Contraindications. Anticholinergic effects potentiated by MAOIs. Potentiates CNS depression with alcohol, other CNS depressants.

Cyproheptadine Adverse Reactions

Adverse Reactions

Drowsiness, dizziness, nervousness, paradoxical excitement, anticholinergic effects, gastritis, hypotension, blood dyscrasias.

Cyproheptadine Clinical Trials

See Literature

Cyproheptadine Note


Formerly known under the brand name Periactin.

Cyproheptadine Patient Counseling

Patient Counseling

Alert patients that antihistamines may diminish mental alertness; however, in young children, they may occasionally produce excitation. 

Alert patients about engaging in activities requiring mental alertness and motor coordination (eg, driving a car or operating machinery).