When teaching a client about isoniazid and rifampin therapy, which instruction is essential to include?

When educating a client about isoniazid and rifampin therapy, it is essential to emphasize the importance of limiting alcohol intake. Both medications can have hepatotoxic effects, meaning they can potentially cause liver damage. Alcohol is also a hepatotoxin, and its consumption can exacerbate the liver-related side effects associated with these drugs, particularly isoniazid. By limiting or avoiding alcohol, patients can reduce their risk of liver injury and ensure that the medications work effectively without unnecessary complications.

In contrast, taking these medications with dairy products is not advisable because isoniazid can bind to calcium, which may reduce its effectiveness. Doubling the dosage if a dose is missed is not recommended because it could lead to toxicity or increased side effects. Additionally, taking the medication with antacids can interfere with the absorption of both isoniazid and rifampin, potentially decreasing their effectiveness. Therefore, stressing the importance of limiting alcohol intake is crucial for the safe and effective use of these medications.