Doxylamine Succinate is a medicine which is used to provide relief from the symptoms of hay fever, common cold, flu, & allergy. It is a type of first generation anti-histamine agent which works by blocking acetylcholine & histamine produced by the body. This medicine also relieves runny nose, watery eyes, and sneezing symptoms of allergic conditions. It is administered orally and gets metabolized in the liver. With the biological half life of about 10 to 12 hours, it is excreted in urine & feces.