## **Core Concept**
Isoniazid-induced peripheral neuritis is a well-known side effect of isoniazid, a first-line antitubercular medication. This condition arises due to the interference of isoniazid with pyridoxine (vitamin B6) metabolism. Pyridoxine plays a crucial role in the synthesis of neurotransmitters and maintaining the health of the nervous system.

## **Why the Correct Answer is Right**
The correct answer, , indicates that patients with **slow acetylator status** are more prone to isoniazid-induced peripheral neuritis. Isoniazid is metabolized by acetylation, a process that converts it into a less active form. Individuals who are slow acetylators have lower levels of the enzyme responsible for this conversion, leading to higher and more sustained levels of isoniazid in the body. This increases the risk of peripheral neuritis because higher levels of isoniazid lead to greater interference with pyridoxine metabolism.

## **Why Each Wrong Option is Incorrect**
- **Option A:** - This option is incorrect because **fast acetylators** would actually have lower levels of isoniazid in their system due to quicker metabolism, reducing the risk of peripheral neuritis.
- **Option B:** - This option does not directly relate to the acetylator status or any well-known risk factor for isoniazid-induced peripheral neuritis.
- **Option C:** - Similarly, this option does not provide a relevant or accurate risk factor for the condition.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that **pyridoxine supplementation** can prevent or treat isoniazid-induced peripheral neuritis. It is recommended to give pyridoxine (usually 10 mg/day) to patients on isoniazid, especially those at higher risk, such as pregnant women, individuals with malnutrition, and those with a history of neuropathy.

## **Correct Answer:** . Slow acetylator.