Possible Causes:a. Black discoloration on the tongue may be due to "black hairy tongue," often triggered by medications or poor oral hygiene.b. Discoloration on the penis is less common and should be evaluated by a healthcare professional.

Immediate Actions:a. Stop taking Neurobion Forte and consult your doctor promptly.b. Maintain good oral hygiene and monitor for other symptoms like pain or swelling.

Consultation:a. Your doctor may recommend stopping the medication and suggest alternative treatments or tests.b. Seek emergency care if you experience symptoms like difficulty breathing or severe rash.