Pharmacology – MCQ 137 – Pyridoxine – drug interactions

Clinically significant drug interaction occurs between pyridoxine and all the following drugs except?
A. Isoniazid
B. Cyclosporine
C. Levodopa
D. Hydralazine

Correct answer : B. Cyclosporine

Pyridoxine – drug interactions :

• INH – induces a pyridoxine deficiency state
• Levodopa – pyridoxine promotes peripheral conversion of levodopa to dopamine – thus it decreases therapeutic action of levodopa in the brain
• Oral contraceptive pills – decrease pyridoxine levels in some females
• Hydralazine – impairment of pyridoxine utilisation
• 4-deoxy pyridoxine – pyridoxine antagonist