Why is vitamin B6 (pyridoxine) prescribed alongside isoniazid?

Vitamin B6, also known as pyridoxine, is prescribed alongside isoniazid primarily to prevent the development of peripheral neuropathy, which is a common side effect of isoniazid treatment. Isoniazid can deplete levels of pyridoxine in the body, leading to neurological symptoms such as nerve inflammation or neuropathy. This is particularly important in patients who may already be at risk for these adverse effects due to pre-existing conditions or nutritional deficiencies.

Administering pyridoxine helps to mitigate these risks by replenishing vitamin B6 levels and promoting proper nerve function, thus reducing the likelihood of uncomfortable and potentially debilitating nerve-related side effects. This consideration is particularly critical in long-term treatments of tuberculosis where isoniazid is commonly used, ensuring patient safety and comfort during their therapy.