Eye drops of which sulphonamide is used clinically ?
**Core Concept**
The sulphonamide group of antimicrobials is used to treat various bacterial infections, including conjunctivitis. The pharmacological principle being tested relates to the application of topical antimicrobials in ophthalmology. **Sulphonamides** are a class of antimicrobials that inhibit bacterial synthesis of folic acid, thereby exerting their bacteriostatic effects.
**Why the Correct Answer is Right**
The correct sulphonamide used clinically in eye drops is **Sulfacetamide**. It is a prodrug that is converted to **sulfanilamide**, which then inhibits the bacterial enzyme **dihydropteroate synthase**. This enzyme is necessary for the synthesis of folic acid, a vital compound for bacterial growth and replication. By inhibiting this enzyme, sulfacetamide exerts its bacteriostatic effects on susceptible bacteria, making it an effective treatment for conjunctivitis.
**Why Each Wrong Option is Incorrect**
* **Option A:** This is not a sulphonamide used in eye drops.
* **Option B:** This is not a sulphonamide used in eye drops.
* **Option C:** This is not a sulphonamide used in eye drops.
**Clinical Pearl / High-Yield Fact**
When using topical antimicrobials like sulfacetamide, it's essential to note that the efficacy of treatment can be compromised by **resistance development**. Regular surveillance of bacterial susceptibility patterns is crucial to ensure the continued effectiveness of these medications.
**Correct Answer:** B. Sulfacetamide