Hi doc, i was a smoker, i feel my heart beat run fast after i smoke & it feel so strong goes to the brain. what is happening?

Smoking: Smoking is one of the risk factors for heart disease and stroke, if you have other risk factors such as hypertension, diabetes, your risk of heart disease and stroke is even higher, i would suggest you see your doctor for evaluation.

Nicotine effect: Once you stop smoking, with time your body tends to forget how to manage the big amounts of nicotine he was used to when you were smoking. If you smoke again, the body needs to get rid of this but is unable to do it in a short period of time and the effects on heart and blood vessels are more noticeable. If you resume your habit these symptoms will become less noticeable.