Derek Burnett
Derek Burnett is a Contributing Writer at Bottom Line Personal, where he writes frequently on health and wellness. He is also a contributing editor with Reader’s Digest magazine.
Even after making lifestyle changes such as a low-sodium diet, exercising, and improved sleep patterns, many people continue to struggle to control their blood pressure. Fortunately, there are numerous hypertension medications that are effective in lowering blood pressure. Your doctor will probably urge you to begin taking an antihypertensive drug if you meet the following criteria:
While blood pressure medications are effective, it’s usually not as simple as starting a drug one day and seeing immediate results. Instead, you may need to take multiple drugs from different classes of medications, gradually raising the dose of each one to find its optimal amount. For some people, this process takes weeks or even months.
Doctors choose from among several classes of drugs based on predicted benefit, interactions with other drugs you might be taking, and potential side effects, which can vary by class. Broadly speaking, the side effects of blood pressure medications may include frequent urination, low potassium, dizziness, dehydration, nausea, thirst, constipation, digestive issues and dry cough. Your healthcare providers will take into account your reaction to whatever drugs you try, looking for the medication or combination of medications deemed most effective and best tolerated by you.
Your doctor’s first choice will likely come from one of four “first-line” classes of antihypertensive drugs: diuretics, angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and calcium channel blockers.
First line: Diuretics
You probably have known people who took diuretics and complained about the common side effect of frequent urination. That occurs because diuretics work by stimulating the kidneys to flush out excess water and sodium, lowering the blood’s total volume. Within the diuretics class are thiazide (and thiazide-like drugs), loop diuretics (often prescribed when there is a fluid overload), and potassium-sparing diuretics.
The most common blood pressure medication within the group of thiazide-like drugs is hydrochlorothiazide (Aquazide, Esidrix, Hydrodiuril and Microzide). But the group also contains two longer-acting drugs, chlorthalidone (Hygroton and Thalitone) and indapamide (Lozol). The longer-acting thiazides appear to be more effective than hydrochlorothiazide, both in lowering blood pressure and in reducing risk of cardiovascular events. Besides increased urination, thiazides can cause fatigue, drowsiness, low blood pressure, erectile dysfunction, increased blood sugar, and gastrointestinal problems. If you have a history of gout, tell your doctor before starting on a thiazide.
Loop diuretics are generally prescribed to people who have heart failure, edema (fluid retention) or kidney disease. The family of loop diuretics includes bumetanide (Bumex), ethacrynic acid (Edecrin), furosemide (Lasix) and torsemide (Demadex). In addition to frequent urination, loop diuretics can cause diarrhea, nausea, dizziness, constipation, headache, dehydration, numbness and tingling and, in the case of furosemide (Lasix), blurred vision.
One of the reasons low potassium is a potential side effect of diuretics is that the body’s potassium gets flushed out along with sodium and water. The potassium-sparing diuretics limit the amount of potassium lost through the drugs’ action. They’re usually prescribed to people whose potassium levels are low, a condition called hypokalemia. The potassium-sparing diuretics are amiloride (Midamor), triamterene (Dyrenium), eplerenone (Inspra) and spironolactone (Aldactone and CaroSpir). People taking potassium-sparing diuretics are at increased risk of high potassium levels (hyperkalemia), nausea, vomiting, headache and increased thirst. Spironolactone specifically may cause breast swelling or tenderness and erectile dysfunction. People with kidney dysfunction should not take potassium-sparing diuretics.
First-line: ACE Inhibitors
When a hormone in our bodies called angiotensin is naturally converted into another form called angiotensin II, the blood vessels become restricted, raising blood pressure. The ACE inhibitors block the conversion of angiotensin into angiotensin II, keeping blood pressure low. ACE inhibitors include benazepril (Lotensin), captopril (Capoten), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil and Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace) and trandolapril (Mavik).
Although most people tolerate ACE inhibitors well, some people do experience headache, loss of taste, nausea, itchy rash, and dizziness. And up to one third of patients develop a persistent dry cough.
First-line: ARBs
While ACE inhibitors work by stopping angiotensin from being converted to angiotensin II, ARBs stop angiotensin II from causing the blood vessels to restrict after it’s already been formed. The family of ARBs consists of azilsartan (Edarbi), candesartan (Atacand), eprosartan (Teveten), irbesartan (Avapro), losartan (Cozaar), olmesartan (Benicar), telmisartan (Micardis) and valsartan (Diovan and Prexxartan). ARBs may cause stuffy or runny nose, back pain, dizziness, fatigue, headache and gastrointestinal problems.
First-line: Calcium channel blockers
You may not think of your arteries as containing muscle tissue, but they do. In order to contract, muscle cells need calcium. Calcium channel blockers work by keeping calcium away from the arteries’ muscle cells so that they remain dilated and blood pressure stays low. There are two subclasses of calcium channel blockers, dihydropyridines and non-dihydropyridines.
The dihydropyridines include amlodipine (Norvasc, Norliqva, Katerzia and Lotrel), felodipine (Plendil), isradipine (DynaCirc), nicardipine (Cardene), nifedipine (Adalat, Afeditab, Nifediac, Nifedical and Procardia) and nisoldipine (Sular).
The non-hydropyridine calcium channel blockers include diltiazem (Cardizem, Dilacor and Tiazac) and verapamil (Calan, Covera, Isoptin and Verelan).
Side effects of calcium channel blockers may include acid reflux, rash, heart palpitations, dizziness, flushing, headache, constipation, and swollen feet and ankles. Calcium channel blockers also have some positive side effects: they sometimes bring relief to people with migraines and other headaches, and they can help with some irregular heart rhythms and with esophageal spasms.
Sometimes a doctor will suggest one of a few different types of blood pressure medications either instead of or in addition to drugs within the four classes that fall into the first-line group.
Alpha Blockers ease blood pressure by relaxing the smooth muscle tissue in the blood vessels. They include doxazosin (Cardura), phentolamine (Regitine), prazosin (Minipress, Prazin and Prazo), and terazosin (Hytrin).
Beta Blockers slow the force and pace of your heart’s beating. Examples include acebutolol (Sectral), atenolol (Tenormin), betaxolol (Kerlone), bisoprolol (Zebeta), metropolol (Lopressor and Toprol), nadolol (Corgard), nebivolol (Bystolic) and propranolol (Inderal and InnoPran).
As their name implies, Alpha-Beta Combo Blockers work similarly to beta blockers and alpha blockers. They are carvedilol (Coreg) and labetalol (Trandate and Normodyne).
Not unlike Beta Blockers, the Alpha-2 Receptor Agonist known as methyldopa slows the heart, by reducing the effects of adrenaline on the sympathetic nervous system.
Central-Acting Adrenergic Inhibitors disrupt signals coming from the brain that would make the heart beat faster and cause the blood vessels to constrict. They include clonidine (Catapres, Duracion, Jenloga, Kapvay and Nexiclon), guanfacine (Tenex and Intuniv), alpha methyldopa (Aldomet) and guanabenz acetate (Wytensin).
Peripheral Adrenergic Inhibitors keep smooth muscle cells from constricting. A drug of last resort, the class includes guanadrel (Hylorel), guanethidine (Ismelin) and reserpine (Serpasil).
Vasodilators work directly on the blood vessels, causing them to expand. Examples are hydralazine (Apresoline) and minoxidil (Loniten).
A Direct Renin Inhibitor called aliskiren (Tekturna) blocks an enzyme called renin which is a precursor to angiotensin. As we’ve seen, angiotensin, in turn, is a precursor to angiotensin II, which causes blood vessels to constrict and blood pressure to rise. Inhibiting renin prevents that process from occurring, keeping blood pressure low.
