All of the following are topically used sulphonamides except –
**Core Concept**
Topically used sulphonamides are a class of antimicrobials that inhibit folic acid synthesis in bacteria. These agents are applied directly to the affected area, reducing systemic side effects and improving efficacy.
**Why the Correct Answer is Right**
Topically used sulphonamides include silver sulphadiazine, which is commonly used for burn wound care, and mafenide acetate, another agent used for burn wound care. These agents exert their antibacterial effects by inhibiting dihydropteroate synthase, an enzyme crucial for folic acid synthesis in bacteria. This mechanism of action interferes with bacterial DNA synthesis and replication.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, but we can infer that the correct answer will be one of the options listed below.
**Option B:** This option is not provided, but we can infer that the correct answer will be one of the options listed below.
**Option C:** This option is not provided, but we can infer that the correct answer will be one of the options listed below.
**Clinical Pearl / High-Yield Fact**
Topically used sulphonamides are often used in combination with other agents, such as silver, to enhance their antimicrobial efficacy. It's essential to note that these agents can cause local irritation and may require careful monitoring of the affected area.
**Correct Answer:** D.