Thanks for your question on Healthcare Magic. I can understand your concern. By your history and description, you must be suffering from laryngitis. Many a times, dry cough without fever, unresponsive to treatment with antibiotics usually results from inflammation in the larynx. You can start warm salt water gargles, stay away from polluted air, avoid smoking (if you do) and give rest to your voice. If you get fever, try changing the antibiotic with your doctor. Antihistaminics like Levocetirizine must help you. Also, paracetamol will help in reducing both headache and inflammation. Even if it is mild allergic reaction, Levocetirizine will work for you. Take care, Regards