For isoniazid, what is the most common toxicity symptom to monitor?

For isoniazid, what is the most common toxicity symptom to monitor?

• A. Hair loss
• B. Nausea
• C. Peripheral neuropathy
• D. Rash

Answer: (C)

Isoniazid commonly affects nerve function because it depletes vitamin B6 (pyridoxine), which is essential for normal nerve health. The most common toxicity symptom to monitor is peripheral neuropathy, which shows up as numbness, tingling, or burning sensations in the hands and feet. This is a hallmark sign and can be prevented or mitigated by giving vitamin B6 alongside isoniazid. While liver toxicity and skin rashes can occur with isoniazid, they are less frequent than neuropathy, and nausea is not as characteristic of its toxicity profile. Regularly asking patients about sensory changes and performing simple nerve checks helps catch this early so supplementation can be used effectively.

Isoniazid commonly affects nerve function because it depletes vitamin B6 (pyridoxine), which is essential for normal nerve health. The most common toxicity symptom to monitor is peripheral neuropathy, which shows up as numbness, tingling, or burning sensations in the hands and feet. This is a hallmark sign and can be prevented or mitigated by giving vitamin B6 alongside isoniazid. While liver toxicity and skin rashes can occur with isoniazid, they are less frequent than neuropathy, and nausea is not as characteristic of its toxicity profile. Regularly asking patients about sensory changes and performing simple nerve checks helps catch this early so supplementation can be used effectively.