Skin darkening after taking anti-tuberculosis drugs may be a result of photosensitization or liver damage; treatments for different causes are different, please follow your doctor’s instructions. 1. Photosensitization: Anti-tuberculosis drugs such as pyrazinamide can cause photosensitization of the skin, which may appear reddish brown or almost black on the parts of the patient’s body that are often exposed to sunlight, and long-term users may have bronze-colored skin. Consider desensitization treatment, such as oral vitamin C as prescribed by the doctor; at the same time, daily attention to sun protection. 2. Liver damage: Anti-tuberculosis drugs such as rifampicin and isoniazid may cause liver damage, and when the liver is damaged, aminotransferases and bilirubin may be elevated, and the skin may turn black and yellow. Mainly according to the indicators of aminotransferases and bilirubin, under the guidance of the doctor to reduce or stop the drug. To summarize, when the skin turns black after taking anti-tuberculosis drugs, you should consult a doctor to find out the cause, and the doctor will give targeted treatment.