Which drug has keratolytic action and reduces sebum production by up to 90 percent?

• A. Isotretinoin
• B. Clindamycin
• C. Benzoyl peroxide
• D. Azelaic acid

Answer: (A)

Isotretinoin stands out because it tackles acne in two powerful ways: it acts as a keratolytic by normalizing the shedding of follicular epithelium, which prevents comedone formation, and it dramatically decreases the activity of the sebaceous glands, reducing sebum production by as much as about 90 percent. That combination meaningfully lowers the oily environment that acne bacteria thrive in and reduces the plugs that clog pores, leading to a substantial and lasting improvement.

Other options provide useful effects but don’t match this dual action. Benzoyl peroxide primarily offers antibacterial benefit with mild keratolysis and does not meaningfully suppress sebum production. Clindamycin is an antibiotic that reduces inflammation and bacterial load but leaves sebum levels largely unchanged. Azelaic acid has keratolytic and anti-inflammatory effects and helps with hyperpigmentation, but its impact on sebum production is not the dramatic reduction seen with isotretinoin.

Because of its unique combination of keratolytic activity and far-reaching suppression of sebaceous output, isotretinoin is the best choice for severe cases where reducing sebum by such a large amount is crucial. Note that isotretinoin requires careful monitoring and awareness of safety considerations due to teratogenicity and potential systemic side effects.