Drug information of Cyproheptadine


Drug group:

Cyproheptadine is a serotonin antagonist and a histamine H1 blocker used as antipruritic, appetite stimulant, antiallergic, and for the post-gastrectomy dumping syndrome, etc.

Mechanism of effect

• Serotonin and histamine antagonist; competitively inhibits H1 receptor, mediating bronchial constriction, smooth-muscle contraction, edema, hypotension, CNS depression, and cardiac arrhythmias.
• prevents histamine release in blood vessels and is more effective in preventing histamine response than in reversing it; may be useful in patients with syndromes sustained by histamine-producing tumors
• Moderate anticholinergic activity with low sedative effect
• May have anti-5HT2 effects
• May have some calcium-channel blocking activity


Cyproheptadine is a piperidine antihistamine. Unlike other antihistamines, this drug also antagonizes serotonin receptors. This action makes Cyproheptadine useful in conditions such as vascular headache and anorexia.
Cyproheptadine does not prevent the release of histamine but rather competes with free histamine for binding at HA-receptor sites. Cyproheptadine competitively antagonizes the effects of histamine on HA-receptors in the GI tract, uterus, large blood vessels, and bronchial smooth muscle.
• Most antihistamines possess significant anticholinergic properties, but Cyproheptadine exerts only weak anticholinergic actions.
• Blockade of central muscarinic receptors appears to account for Cyproheptadine's antiemetic effects, although the exact mechanism is unknown.
• Cyproheptadine also competes with serotonin at receptor sites in smooth muscle in the intestines and other locations.
• Antagonism of serotonin on the appetite center of the hypothalamus may account for Cyproheptadine's ability to stimulate appetite.
• Cyproheptadine also has been used to counter vascular headaches, which many believe are caused by changes in serotonin activity, however it is unclear how Cyproheptadine exerts a beneficial effect on this condition.


Peak plasma time : 6-9 hr
Metabolized by glucuronidation via UGT1A
Metabolites: Quaternary ammonium glucuronide conjugate
Excretion: Urine (40%), feces (2-20%)

Drug indications

Migraine , Urticaria , Allergic Rhinitis


Hypersensitivity Reaction
4 mg PO q8hr initially; maintenance: 4-20 mg/day, up to 32 mg/day divided q8hr in some patients; not to exceed 0.5 mg/kg/day
Spasticity Associated With Spinal Cord (Off-label)
2-4 mg PO q8hr initially; not to exceed 24 mg/day
Migraine Headache Prophylaxis (Off-Label)
2 mg PO q12hr with or without propanol
Decreased Appetite Secondary to Chronic Disease (Off-label)
2 mg PO q6hr for one week; THEN 4 mg PO q6hr
Drug-Induced Sexual Dysfunction (Off-label)
4-12 mg PO 1-2 hours before anticipated coitus or 1-16 mg/day
Serotonin Syndrome (Off-Label)
12 mg initially PO, followed by 2 mg q2hr or 4-8 mg PO q6hr as needed to control symptoms


• Use caution in cardiovascular disease, including hypertension and ischemic heart disease, patients with increased intraocular pressure, history of asthma or other chornic breathing disorders, thyroid dysfunction and renal insufficiency.
• Avoid use in elderly because of high incidence of anticholinergic effects; may exacerbate existing lower urinary conditions or benign prostatic hyperplasia; if used, administer at low end of dosage range
• May cause CNS depression, which may impair mental abilities; use caution when operating heavy machinery
• Use with care in children.Do not give this medicine ( cyproheptadine tablets ) to a premature baby or a newborn.
• You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.

Points of recommendation

• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine ( cyproheptadine tablets ) affects you.
• Take with or without food. Take with food if it causes an upset stomach.

Pregnancy level


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