Smoking and second-hand smoke from cigarettes, cigars, and pipes can contribute to headaches for both the smoker and the non-smoker. Nicotine, one of the components of tobacco, stimulates the blood vessels in the brain to constrict (narrow). Smoking also stimulates the nerves in the back of the throat, contributing to headache pain.
Usually, by removing the stimulus (nicotine), headaches will be relieved. Quitting smoking or reducing exposure to second-hand smoke is especially helpful for those with cluster headaches. In one study of people with cluster headaches, those who reduced their tobacco use by less than one-half pack of cigarettes per day found their headaches decreased by 50%.
Silent migraines are a medical oddity. How can you have a migraine "headache" without headache pain? The answer lies in the still unfolding mystery of migraine. WebMD explains silent migraines, including their unusual symptoms.