Wednesday, February 14, 2018

Dexchlorpheniramine Antihistamincs drug and its Pharmacology

INTRODUCTION-  It is an antihistamine with anticholinergic properties used to treat allergic conditions .
It is the pharmacologically active dextrorotatory isomer of chlorpheniramine.

MECHANISM OF ACTION-
 Its primary mechanism of action being its ability to reduce acetylcholine levels in the brain.

PHARMACOKINETICS-
Distribution-69% to 72% protein bound
Elimination-The t 1/2 is 20 to 24 h. Approximately 19% of dose is excreted in urine as parent drug and metabolites in 24 h.

DRUG DRUG INTERACTIONS-
DEXCHLORPHENIRAMINE+ALCOHOL= Will potentiate the sedative effects of dexchlorpheniramine.
DEXCHLORPHENIRAMINE+MAOs = May cause severe hypotension.

SIDE EFFECTS-
*  allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
*  agitated, nervous, excitable
*  breathing problems
*  changes in vision
*  fast, irregular heartbeat
*  seizures

CONTRAINDICATIONS-
Treatment of lower respiratory tract symptoms; MAOI therapy; any component of the product or other antihistamines of similar chemical structure. Antihistamines also are contraindicated in newborn or premature infants, and breast-feeding mothers.

THERAPEUTIC USES-
 Treatment of:
* perennial and seasonal allergic rhinitis.
* vasomotor rhinitis.
* allergic conjunctivitis.
* mild, uncomplicated allergic skin manifestations of urticaria and angioedema.
* amelioration of allergic reactions to blood or plasma.
* Dermographism.
* adjunctive anaphylactic therapy.

REFERENCE: Tripathi K.D, "Essentials of Medical pharmacology", Edition 7th, page no.-164

No comments:

Post a Comment