Your symptoms of cold, nasal blockage, and dry cough are common in viral upper respiratory infections. Ambrolite D contains chlorpheniramine (an antihistamine), dextromethorphan (a cough suppressant), and phenylephrine (a decongestant), which can help relieve these symptoms.

• Use with caution: If your nasal blockage has improved but you still have a dry cough, Ambrolite D may help reduce coughing, especially if it worsens in air-conditioned rooms.

• Considerations: Avoid using it if you have high blood pressure, glaucoma, or certain heart conditions, as phenylephrine can raise blood pressure.

• Non-medication advice: Keep the room well-ventilated, avoid dry air, and stay hydrated to ease coughing.

• When to see a doctor: If cough persists beyond 2 weeks, worsens, or you develop fever, difficulty breathing, or chest pain, seek medical evaluation.

Always follow the dosage instructions on the package or as advised by a doctor. If unsure, consult your doctor or pharmacist before starting Ambrolite D to ensure it is safe for you based on your health history.To narrow down potential causes, we will need some more information.Please provide your age and gender. Also, it sounds like you've been dealing with a cold, nasal congestion, and a dry cough.