How does weight affect the dosing of INH?

The dosing of isoniazid (INH) is indeed based on body weight, which is critical for ensuring efficacy while minimizing the risk of toxicity. Isoniazid is an antimicrobial medication primarily used to treat tuberculosis, and its pharmacokinetics can be influenced by the individual's body weight.

When dosing is tailored according to weight, it allows for a more precise calculation of the required amount of drug necessary to achieve therapeutic effects. For example, in adults, the recommended dosage is often expressed as a certain milligram amount per kilogram of body weight. This approach acknowledges that individuals with higher body weights may require higher absolute doses to achieve effective drug concentrations, while those with lower body weights may need less.

This individualized dosing helps avoid complications, such as underdosing, which could lead to treatment failure, or overdosing, which could increase the risk of adverse effects. Therefore, tailoring the INH dosage on the basis of body weight is a crucial component of effective tuberculosis treatment.