Smoking is one of the worst habits for blood pressure and overall health. Smoking can damage the lining of the blood vessels, increase plaque buildup, narrow the arteries, and raise blood pressure. Smoking can also reduce the effectiveness of some blood pressure medications, such as beta-blockers and calcium channel blockers. Therefore, people who are taking blood pressure medicine should avoid smoking at all costs. Smoking can also interfere with the metabolism of some cannabinoids, such as THC and CBD. This means that smoking cannabis may alter the effects and duration of these compounds in the body.