Smoking causes a rise in blood pressure. The reason why smoking is dangerous is because it is responsible for causing high blood pressure as well as many other diseases. Different ways are there to help quit smoking. It is advisable to use an option which has no side effects and is effective too. An increase in blood pressure is not caused by smoking alone. The constriction of the blood vessels is caused by the chemicals in cigarettes. The heart has to pump with greater force to circulate blood to all the tissues of the body when the blood vessels are narrowed. The heart rate will increase, besides a rise in the blood pressure. The oxygen in your system will get replaced by the chemicals which are in the cigarette when you are smoking it and inhaling nicotine. The oxygen circulating in the body will be much lesser this way. The nicotine is responsible for causing the adrenal gland to secrete the hormone adrenaline, which leads to the constriction or narrowing of the blood vessels.