Disulfiram-like reaction is caused by: Kerala 11
**Core Concept**
A disulfiram-like reaction is a pharmacological phenomenon characterized by the inhibition of aldehyde dehydrogenase, an enzyme responsible for the breakdown of acetaldehyde, a toxic byproduct of ethanol metabolism. This reaction leads to the accumulation of acetaldehyde, causing symptoms such as flushing, nausea, vomiting, and palpitations.
**Why the Correct Answer is Right**
Metronidazole, an antibiotic used to treat various infections, including amoebiasis and giardiasis, is known to cause a disulfiram-like reaction. This is due to its ability to inhibit aldehyde dehydrogenase, leading to the accumulation of acetaldehyde. The mechanism involves the reduction of nitro group in metronidazole by cellular enzymes, resulting in the formation of reactive intermediates that inhibit aldehyde dehydrogenase.
**Why Each Wrong Option is Incorrect**
**Option A:** Acamprosate is a medication used to treat alcohol dependence by stabilizing glutamate and GABA neurotransmission, but it does not cause a disulfiram-like reaction.
**Option C:** Tetracycline, an antibiotic, does not have a known mechanism of action that involves the inhibition of aldehyde dehydrogenase.
**Option D:** Digitalis, a cardiac glycoside used to treat heart failure and atrial fibrillation, does not have a disulfiram-like reaction.
**Clinical Pearl / High-Yield Fact**
It is essential to note that patients taking metronidazole should avoid consuming alcohol, as it can lead to a disulfiram-like reaction. This is a critical consideration in forensic medicine, as it can be a clue in cases of suspected tampering or poisoning.
**✓ Correct Answer: B. Metronidazole**