Unit 13 Genitourinary and Arthritis Agents

Question 0

Colchicine is a substrate for CYP3A4 and P-gp. Which antimicrobials should be avoided ?

Answer 0

Antimicrobials that can inhibit both 3A4 and P-gp :
Macrolides: erythromycin and clarithromycin (not Azithromycin)

Result: colchicine toxicity- rhabdomyolysis, pancytopemia, multiple organ failure, GI toxicity, can be fatal !

Question 1

Phosphodiesterase inhibitors such as Sildenafil (Viagra), Tadalafil (Cialis), and Vardenafil (Levitra) should not be used with :

Answer 1

Alpha 1 Adrenergic Antagonists such as the vasodilators, terazosin (Hytrin) and doxazosin (Cardura).

Can produce additive effects of drugs used for ED and hypotension !

Question 2

Primary treatment for BPH

Answer 2

Surgery

Finasteride to prevent growth of prostate over long term