Which of the following is a common side effect of TB medications?

Hepatotoxicity is indeed a common side effect associated with many tuberculosis (TB) medications, particularly first-line drugs such as isoniazid and rifampicin. These medications can lead to inflammation and damage to the liver, which is critical to monitor due to the severe implications it can have on a patient's overall health. Regular liver function tests are often recommended during TB treatment to detect any signs of hepatotoxicity early, as managing this side effect is essential for the safe continuation of TB therapy.

The other options, while they may occur in certain populations or under specific circumstances, are not as directly associated with TB medications. Weight gain can be influenced by various factors, including overall health and nutrition, but it is not a typical side effect of the medications used to treat TB. Hypotension is also not commonly linked to TB drug treatments as a major side effect. Diarrhea may occur due to antibiotic use or secondary infections but is less severe than hepatotoxic effects and not as characteristic of TB therapies. Understanding the prominent risks of hepatotoxicity helps align patient care and monitoring during treatment for tuberculosis.