- Diseases, Disorders & Conditions
A Quick Guide to Your Anti-Hypertensive Medications
Hypertension is defined by an elevated systolic blood pressure of more than 140 or diastolic blood pressure of more than 90. Hypertension could cause end-organ damage as mentioned in my hub “Knowing Hypertension and Its Dreaded Complications”. Controlling hypertension to acceptable levels is the target of all physicians among their hypertensive patients. This hub is a quick guide to the common anti-hypertensive medications so you’ll be familiar with them when a doctor would prescribe you one.
Diuretics are anti-hypertensive medications that would eventually make you urinate. They can be used as first line agents against hypertension unless there are contraindications in their use. Diuretics are subdivided into the following:
This type lowers blood pressure by increasing sodium and water excretion. This would in turn lower extracellular volume and eventually decrease blood pressure. Since they take action in the kidneys, they are not that effective when the kidney function is impaired. Thiazides could decrease body potassium and increase uric acid. Potassium levels should be monitored when taking this diueretic. Example of this is Hydroclorothiazide.
This type compared to your thiazides exerts its action even though the kidney is not functioning well and could decrease renal vascular resistance hence decreased blood pressure. Example of this type is Furosemide.
In contrast to your thiazides, this type could decrease potassium excretion in the urine but has the same mechanism of lowering blood pressure as the thiazides. Example of this type is Spironolactone.
This anti-hypertensive decreased blood pressure by decreasing cardiac output because they tend to slow down your heart. They could also sodium and water retention by decreasing production of the hormone “renin” in the kidneys. Beta blockers are effective anti-hypertensive agents in patients with other disease especially in someone who has a previous heart attack. Since beta blockers slow down your heart, this is one of their side effects, they could cause bradycardia (heart rate below 60). Aside from bradycardia, they could also cause insomnia and sexual dysfunction in males. This drug is contraindicated among patients with asthma and COPD. Examples of this group are Metoprolol, and Propranolol.
ACE stands for angiotensin-converting enzyme, an enzyme which could elevate blood pressure to a number of mechanisms. By blocking this enzyme, this group lowers blood pressure by lowering peripheral resistance. It could also decrease sodium and water retention by inhibiting aldosterone, a hormone responsible for water and sodium retention. Side effects include cough, rash, hypotension (BP below normal) and renal failure could occur if given to someone with bilateral renal artery stenosis (a blockage in the renal artery). Examples of this group include your Captopril and Enalapril.
ARB stands for angiotensin receptor blocker, which is part in the cascade of producing angiotensin II which is a potent inhibitor. It has the same effects of ACE inhibitors but its side effects are less troublesome than the ACE inhibitors. ARB blockers are given to patients who are intolerant to ACE inhibitors. Examples in this group include your Losartan, Irbesartan and Telmisartan.
Same with the previous two classes of anti-hypertensives, this class also inhibits renin which is part in the cascade of producing angiotensin II. Side effects include diarrhea, cough and even angioedema. The example for this group is Aliskiren.
Calcium Channel Blockers
This group of anti-hypertensives could decrease blood pressure among patients with diabetes and patients with angina symptoms (chest pain). They decreased blood pressure by blocking calcium, an electrolyte important in maintain the vascular tone of blood vessels both in the heart and the peripheral vessels. By blocking calcium, the mentioned vessels would dilate and therefore decrease blood pressure. Side effects include constipation, headache and dizziness. Examples of this group are Amlodipine, Verapamil, and Nifedipine.
Alpha receptor blocker
This group decrease blood pressure by decreasing peripheral vascular resistance by relaxing both arterial and venous smooth muscles. Aside from hypertension, this group could also be used in the treatment of prostatic hyperplasia. Syncope and tachycardia are its side effects. Examples of this group are Prazosin and Terazosin.
There are still anti-hypertensive medications not discuss in this group, but the ones listed above are the commonly used in the treatment against hypertension. Before trying any anti-hypertensives, seek consult with your physician for proper prescription of anti-hypertensive medications