BROMOCRIPTINE

BROMOCRIPTINE

BRAND NAME:-  PROCTINAL, SICRIPTIN,PARLODEL,1.25,2.5mg tabs, ENCRIPT 2.5,5mg tabs.

BROMOCRIPTINE is synthetic ergot derivative 2- bromo- alpha - ergocryptine is a potent dopamine agonist; most of its actions are based on this property. It has greater action on D2 receptors, while at certain dopamine sites in the brain it acts as a partial agonist or antagonist of D1 receptors. It is also a weak alpha adrenergic blocker but not an oxytocic .

PHARMACOKINETICS:-

Only ⅓ of an oral dose of bromocriptine is absorbed; bioavailability is further lowered by high first pass metabolism in liver . Even then ,it has higher oral: parenteral activity ration than ergotamine. Metabolites are excerted mainly in bile. Its plasma t½ is 3-6hours.

MECHANISM OF ACTION:- 

BROMOCRIPTINE has greater action on D2 receptors, while at certain dopamine sites in the brain it acts as a partial agonist or antagonist of D1 receptors. It is also a weak alpha adrenergic blocker but not an oxytocic.

• Decrease prolactin release from pituitary by activating dopaminergic receptors on lactotrope cells: is a strong antigalactopoietic .

• Increases GH release in normal individuals,but Decreases the same from pituitary tumors that cause acromegaly.

• Has levodopa like action in CNS — anti–parkinsonian and behavioral effects.

• Produces nausea and vomiting by stimulating dopaminergic receptors in the CTZ .

• Hypotension — dur to central suppression of postural reflexes and weak peripheral a adrenergic blockade.

• Decreases Gastrointestinal motility.

USED:-

Used in treatment of Hyperpolactinemia, Acromegaly, Parkinosonism, Diabetes mellitus (DM), Hepatic coma & 

Bromocriptine suppresses lactation and breast engorgement in case of neonatal death,but is not recommended due to unfavorable risk : benefit ratio 

SIDE EFFECTS:-

Are frequent and dose related.

EARLY:- Nausea, vomiting, constipation,nasal blockage. Postural Hypotension may be marked at initiation of therapy — syncope may occur if starting dose is High. Hypotension is more likely in patients taking antihypertensive.

LATE :- Behaviour alterations, mental confusion, hallucinations, psychosis —are more prominent than with levodopa.

Abnormal movement,livedo reticularis .

DOSE:-  Initially 1.25 mg once at night, increase as needed upto 5mg TDS .