Hi.. Thanks for the query.. Bleeding from mouth can occur due to a number of causes like localised gum infection while bleeding can also be from upper respiratory tract, throat, sinuses and upper digestive tract.. You should immediately consult an Emergency room and get evaluated.. A thorough clinical examination can be done followed by investigations to narrow done the cause like upper G.I Endoscopy, sinus x ray, chest x ray, laryngoscopy etc can help.. Treatment can be advised only after the cause is ruled out.. Hope this helps.. Regards..