Hi! First off, clopidogrel is not a blood pressure medication. It s an antiplatelet drug, something that we use to prevent blood from clotting. The list of meds would be something that I would prescribe for someone with angina/a previous heart attack or stroke. Here s the breakdown of the drugs and what they are meant to do: 1. lisonopril - works by causing the vessels in the body to dilate (or relax and widen). This in turn causes there to be less resistance against which the heart has to pump - think of it as a water hose, if the hose has a larger diameter, the water pressure needed to push the water out of the hose is much less than if the hose was of a smaller diameter. It also works at the kidney level to control blood pressure (that s another topic for another day) 2. Metoprolol - works not only by causing the blood vessels to widen, but also decreases the tension of the heart muscle. This in turn leads to there being more blood flow and thus oxygen available to the heart muscle - taking the hose analogy one step further, imagine if the hose is really elastic, and a fat guy stands on it - no water (and in the heart s case, blood) can flow through it. Diltiazem - acts like metoprolol but by a different mechanism, it affects calcium channels in the cells. All these drugs work synergistically to lower blood pressure, it s like trying to hit the enemy at all fronts. However, less meds is always better, so unless your blood pressure is really uncontrollable by just 1 or 2, your doctor might start you on a third. Just be aware of the side effects of the medications, and have regular checks with your doctor and you should be fine.