What symptoms should prompt immediate medical attention in a patient taking INH?

The symptoms of jaundice, severe abdominal pain, or unusual bleeding indicate potential severe liver complications, which are crucial to recognize in patients taking isoniazid (INH). INH is known for its hepatotoxicity, meaning it can cause liver damage, which may lead to hepatitis or liver failure.

Jaundice manifests as a yellowing of the skin and eyes, indicating an accumulation of bilirubin due to liver dysfunction. Severe abdominal pain can suggest acute liver inflammation or injury, while unusual bleeding points to a possible drop in liver function affecting the body's ability to produce clotting factors. Given the severity of these symptoms and the risk of significant liver damage associated with INH, they warrant immediate medical evaluation and intervention to prevent serious health consequences.

In contrast, minor headaches, fatigue, sleepiness, and skin itching may not require urgent medical attention and can often be managed with closer monitoring or symptomatic treatment. Recognizing the more severe manifestations allows for timely medical intervention, which can significantly improve patient outcomes.