Sleep apnea is a serious breathing problem that occurs and interrupts breathing during sleep. Some of its top causes are obesity, hypertension, sedatives addiction, enlarged tonsillitis, smoking, excessive alcohol consumption, allergy, etc. Some of its symptoms that show you might have sleep apnea are waking up frequently in the middle of the night, feeling tired after awakening, mood swings, depression, dry mouth, sore throat, morning headache, etc. On experiencing these symptoms it is advised to visit an ENT specialist to know the root cause of the problem.