Blood pressure medications are life-saving treatments but each is associated with its own risks and benefits, which dictates customizing the selection of drugs for each individual. According to the National Institutes of Health more than one medication from different classes is usually required to lower blood pressure, which further complicates individualized selection. Combination products are available if taking more than one medication causes problems in compliance to the treatment plan over time.
Classes
The large number of blood pressure drugs available are grouped into several classes depending on their method of action for lowering blood pressure. The American Heart Association reports the common classes of blood pressure medicines to include diuretics, beta blockers, angiotensin-converting enzyme inhibitors, or ACEs, angiotensin-receptor blockers, or ARBs, calcium-channel blockers, alpha blockers and vasodilators.
Actions
The different classes of medications, notes the AHA, have different actions: Diuretics help the kidneys to remove extra salt and water from the body so there is less fluid in the blood vessels, which lowers blood pressure. Beta blockers lower blood pressure by decreasing heart rate, the amount of work done by the heart and the amount of blood pumped by the heart. ACEs and ARBs work by different methods to prevent the actions of a hormone called angiotensin II, which makes blood vessels tighten. The result is more relaxed and open blood vessels and lowered blood pressure. CCBs slow the entry of calcium into the muscle cells of blood vessels, which opens blood vessels and lowers blood pressure. Alpha blockers lower blood pressure by blocking the hormone norepinephrine from making blood vessels tighten, resulting in more relaxed and open blood vessels which let blood flow more easily. Vasodilators work by relaxing the muscle in blood vessels, which opens the blood vessels, eases blood flow, and lowers blood pressure.
Single Products
Three types of diuretics are available which include thiazide, loop and potassium-sparing diuretics. Examples of thiazide diuretics include chlorothiazide, hydrochlorothiazide, indapamide, and metolazone. Loop diuretics are bumetanide, furosemide and torsemide. Potassium-sparing diuretics include amiloride, spironolactone and triamterene. Examples of beta blockers are acebutolol, atenolol, betaxolol, bisoprolol, metoprolol, nadolol, penbutolol, pindolol, propranolol and timolol. Beta blockers that have an additional alpha blocking action are carvedilol and labetalol. The ACE class includes benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, perindopril, quinapril, ramipril, and trandolapril. ARBs include candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, and valsartan. Medications in the CCB class include amlodipine, bepridil, diltiazem, felodipine, isradipine, nicardipine, nifedipine, nisoldipine, and verapamil. Alpha blockers include doxazosin, prazosin, and terazosin. Examples of vasodilators are hydralazine and minoxidil.
Combination Products
Beta blocker and diuretic combination products include bisoprolol-hydrochlorothiazide, metoprolol-hydrochlorothiazide and timolol-hydrochlorothiazide. Examples of ACE and diuretic combinations are benazepril-hydrochlorothiazide, captopril-hydrochlorothiazide, and enalapril-hydrochlorothiazide. Combinations of ACEIs and CCBs include amlodipine-benazepril hydrochloride, enalapril-felodipine, and trandolapril-verapamil. ARB and diuretic combinations include candesartan-hydrochlorothiazide, losartan-hydrochlorothiazide, and valsartan-hydrochlorothiazide. CCB and ARB combinations include amlodipine-valsartan and amlodipine-olmesartan.
Newer Generation
Renin inhibitors are examples of a newer generation of products for lowering blood pressure, according to 2009 information from the Harvard Medical School. These medications work by inhibiting an enzyme called renin whose action is to control angiotensin II levels in the body. Lowering angiotensin II by blocking renin results in the opening of blood vessels and lowering of blood pressure. Aliskiren, which was FDA approved in 2007, is an example of a currently available renin inhibitor.
References
- National Institutes of Health: The Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure
- American Heart Association: Types of Blood Pressure Medications
- U.S. Food and Drug Administration: High Blood Pressure Medicines
- Harvard Medical School: Medications for Treating Hypertension
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