Hi Dear , Welcome to HCM. Understanding your concern. As per your query you have persistent cough despite taking Promethazine . The symptoms you mentioned in query are pointing towards condition known as severe upper respiratory tract infection. The infection is probably a strep throat which due to lack of treatment has spread to ear through eustachian tube and deep in to respiratory track and causing respiratory problem. The symptoms can also occur due to allergic reaction like asthma. You may have lung infection or bronchitis. Do warm saline gargles with pinch of salt water. Take expectorants. Steam inhalation is very effective for you. I would suggest you to consult ENT specialist without any delay . Doctor may order blood test , throat swab test or virus culture test. You should get an x ray of the chest and Immunoglobulin G levels checked for further treatment and also consult chest specialist . Doctor may prescribe amoxicillin or penicillin at least for 10 days along with decongestants and mucolytic agents . For now do warm saline rinses , take rest. Mast cell stablizers such as sodium cromoglycate is effective to prevent infection. You should avoid hot, sharp and spicy foods. . Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari