Medical Today

Pharmacology.

Leflunomide’s active metabolite (M1) inhibits dihydro-oratate dehydrogenase, thereby inhibiting pyrimidine biosynthesis. M1 exhibits immunomodulating and anti-inflammatory effects.

Administration and Adult Dosage.

PO for rheumatoid arthritis 100 mg/day for 3 days, then 20 mg/day. Reduce dose to 10 mg if 20 mg is not tolerated.

Pediatric Dosage.

Safety and efficacy not established.

Geriatric Dosage.

Same as adult dosage.

Dosage Forms.

Sildenafil (Viagra) was developed more than 10 years ago as an antihypertensive and antianginal drug. It proved ineffective in these applications but was shown to affect the smooth muscles of the penis.

Pharmacology.