Prototype Drug Unit 3 & 4- Finasteride (Proscar)

Question 1

Therapeutic classification

Answer 1

Drug for BPH

Question 2

Pharmacologic classification

Answer 2

Antiandrogen, 5-alpha reductase inhibitor

Question 3

Therapeutic effects and uses

Answer 3

Inhibits the metabolism of testosterone. Shrinks enlarged prostates, helping to restore urinary function. Prescribed in combination with doxazosin to reduce the risk of symptomatic progression of BPH.

Question 4

Mechanism of action

Answer 4

Acts by inhibiting 5-alpha reductase, which is the enzyme responsible for converting testosterone to one of its metabolites. Promotes regression of prostate epithelial tissue and decreases mechanical obstruction of the urethra

Question 5

Route

Answer 5

PO

Question 6

Absorption

Answer 6

Well absorbed

Question 7

Distribution

Answer 7

Crosses the blood-brain barrier; found in semen; 90% bound to plasma protein

Question 8

Metabolism

Answer 8

Hepatic

Question 9

Excretion

Answer 9

39% renal, 57% feces

Question 10

Adverse effects

Answer 10

sexual dysfunction, decreased libido, decreased ejaculate volume, gynecomastia

Question 11

Contraindications/Precautions

Answer 11

Contraindications: hypersensitivity, pregnancy, lactation, females, and children. (Pregnant nurse or pharmacist should avoid handling crushed medication because it may be absorbed through the skin.

Precautions: hepatic or renal impairment

Question 12

Drug interactions

Answer 12

Anticholinergics may decrease the effects. Testosterone will result in a reduction in the effects of both drugs

Question 13

Herbal/food interactions

Answer 13

Saw palmetto may potentiate the effects of finasteride

Question 14

Pregnancy Category

Answer 14

X