Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern.. As per your complain drainage down the throat also known as Post nasal drip can occur due to causes like Sinusitis, Upper Respiratory Track infection, acid reflux, allergies etc.. It can cause irritation and infection in throat that is lead to cough reflex.. I would suggest you to consult an Otolaryngologist and get evaluated and a thorough clinical evaluation and investigations like PNS View x ray, nasal endoscopy, upper G.I Endoscopy etc can help in diagnosis and treatment can be planned accordingly.. In case of infection you can be advised to take a course of antibiotics, ant-inflammatory painkiller, decongestants oral as well as nasal spray, anti allergics and mucolytics.. As of now you can take anti allergics like Levocetrizine, Mucolytics like Ambroxol.. If it is due to acid reflux antacids and proton pump inhibitors like Omeprzole and diet modifications can be advised.. In case of allergies anti allergics and preventing exposure to allergen can be advised.. Do warm saline gargles and steam inhalations.. Limit exposure to dust and also avoid chilled foods.. Sip on warm water.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.