## **Core Concept**
Gastric wash, also known as gastric lavage, is a procedure where the stomach is flushed with liquids to remove harmful substances. The decision to perform a gastric wash is influenced by the risk of aspiration and the potential benefit of removing toxic substances. It is crucial to consider the patient's condition and the timing of the ingestion.

## **Why the Correct Answer is Right**
The correct answer, corrosive poisoning (option C), is a condition where gastric wash is contraindicated because the corrosive substances can cause severe damage to the esophagus and stomach. Performing a gastric wash in such cases can lead to further damage, including perforation of the esophagus or stomach.

## **Why Each Wrong Option is Incorrect**
- **Option A:** In cases of drug overdose, gastric lavage might be considered if the patient presents early after ingestion, but it's not a strict contraindication. The decision is based on the timing and the substance ingested.
- **Option B:** In gastrointestinal bleeding, gastric lavage might be used diagnostically or therapeutically to clear the stomach of blood, but it's not universally contraindicated.
- **Option D:** In food poisoning, gastric lavage is rarely indicated and usually not recommended due to the risk of aspiration and the fact that most pathogens have already been absorbed.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that in cases of corrosive ingestion, the primary goal is to assess and stabilize the patient, with a focus on endoscopic evaluation rather than immediate gastric lavage. The mnemonic "DO NOT DO" can help recall that in corrosive poisoning, one should not perform gastric lavage.

**Correct Answer: C. Corrosive poisoning**