Periactin: profile and news

Namibia: New Info in Teek's Case Apr 25, 2006
..."Whilst they were swimming, I went to lie on my bed as I had taken a Periactin tablet and had some beer to drink and I was extremely drowsy and sleepy.". ... - AllAfrica.com,

Other information

Indication
For treatment of perennial and seasonal allergic rhinitis, vasomotor rhinitis, allergic conjunctivitis due to inhalant allergens and foods, mild uncomplicated allergic skin manifestations of urticaria and angioedema, amelioration of allergic reactions to blood or plasma, cold urticaria, dermatographism, and as therapy for anaphylactic reactions adjunctive to epinephrine.

Pharmacology
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.

Mechanism Of Action
Cyproheptadine competes with free histamine for binding at HA-receptor sites. This antagonizes the effects of histamine on HA-receptors, leading to a reduction of the negative symptoms brought on by histamine HA-receptor binding.

Drug Category
Anti-allergic Agents; Gastrointestinal Agents; Antipruritics; Antihistamine derivatives; ATC:R06AX02

Brand Names/Synonyms
Cypoheptadine; Cyproheptadiene; Cyproheptadine; Cyproheptadine Hcl; Dibenzosuberonone/Cyproheptadine; Dronactin; Eiproheptadine; MK 141; Periactin; Periactine; Periactinol; Peritol

Dosage Forms
SYRUP;TABLET

Absorption
Well absorbed after oral administration.

Interactions
Interactions for Cyproheptadine:

MAO inhibitors prolong and intensify the anticholinergic effects of antihistamines. Antihistamines may have additive effects with alcohol and other CNS depressants, e.g., hypnotics, sedatives, tranquilizers, antianxiety agents.

Chemical IUPAC Name
Not Available

Chemical Formula
C21H21N

Half Life
Not Available

Drug Type
Approved Drug

# Accession No
APRD00033

CAS Registry Number
129-03-3