In what way might INH affect patients with a history of seizures?

Isoniazid (INH) can adversely affect individuals with a history of seizures by decreasing the seizure threshold. This means that in patients who have a predisposition to seizures, the likelihood of experiencing a seizure may rise when they are treated with INH.

The mechanism behind this is related to the pharmacological effects of INH on the central nervous system. Isoniazid can lead to the accumulation of certain neurotransmitters or metabolic byproducts that may provoke neuronal excitability, subsequently increasing the risk of seizures. This effect is particularly concerning for patients with a known history of seizures, as it can exacerbate their condition.

In contrast, options like improved seizure control or having no effect on seizure activity do not accurately reflect the potential risks associated with INH. Therefore, the understanding that INH can lower seizure thresholds is crucial for managing patients with a history of seizures effectively.