In the last article I began a series on blood pressure and, as promised, will be continuing the discussion on some of the anti-hypertensive medications.

The first class of anti-hypertensive medications we will be addressing are the diuretics. Diuretics are commonly called ‘water pills’, because they cause the removal of water and sodium from the kidneys. They are the oldest and least expensive class of drugs used to treat hypertension. By forcing the kidneys to eliminate sodium and water from the body they cause the decrease of blood volume, so that the heart has to pump less blood with each beat. This in turn causes a lowering of the blood pressure. Loop diuretics and thiazide diuretics are so named because they each affect a different part of the kidney tubule.

One of the drawbacks of diuretics is that they deplete potassium, so if a patient takes these drugs he may need potassium supplements. Doctors do sometimes prescribe a potassium-sparing diuretic, to counteract potassium depletion. However, these drugs can in turn cause dangerously high levels of potassium in some patients. They also directly or indirectly block aldosterone, a hormone that raises blood pressure, by causing the kidneys to conserve sodium and water.

Diuretics are thought to be especially effective for the salt-sensitive patient with hypertension, and older patients with isolated systolic hypertension (hypertension as a result of a high systolic value on blood pressure). We are commonly led to believe that everyone is salt-sensitive. However, the truth is that this condition affects only a small percentage of the population.

Common side effects of the loop and thiazide diuretics include weakness, confusion, potassium depletion, gout, fatigue, thirst, cardiac arrhythmias, hyperglycemia, which can lead to diabetes, frequent urination, lightheadedness, muscle cramps, diarrhea, or constipation, increased sensitivity to sunlight, allergic reaction in people sensitive to sulfa drugs, and impotence. Special mention should be made of the loop diuretic furosemide which causes thiamine deficiency that can lead to heart failure. If one is taking this drug it is imperative the B vitamins be supplemented. And the potassium diuretics have other side effects like excessive potassium levels, especially in patients with kidney disease, breast enlargement and erectile dysfunction in men, menstrual irregularities in women, headache, dizziness, diarrhea, fatigue, upset stomach, and breast tenderness.

Diuretics seem to perform as well or slightly better than the newer drugs in controlling blood pressure and preventing complications such as stroke and heart failure. These results and the low cost of diuretics prompted the JNC to recommend thiazide diuretics as the first line of treatment for most people with hypertension. For people with certain health problems, including diabetes, kidney disease, or heart failure, other medications may be a safer first choice.

Each of the above-mentioned drugs is designed to reduce the volume of blood in the body by removing water and sodium from the system. Although they are considered the best first choice most of the time there are obviously several side effects which can result from taking them. So again, the one question that I habitually ask is, if the blood pressure is elevated can a pathological cause be identified that is causing this to occur? If not, then is it really necessary to force the blood pressure down into a ‘normal’ range? If we listen to the highly promoted medical think then we are destined to end up on some type of high blood pressure medication if the blood pressure exceeds 140/90. What used to be considered as high-normal is now considered to be the first stage of hypertension and medication is thought to be the solution. If this is the case, then in five or ten years where will the lines be drawn? Is this numbers game going to follow the whole cholesterol numbers game? It seems likely. I submit to you that in order to promote the pharmaceutical profiteering industry a pattern has been set and as long as the public buys into it the control of big Pharma will continue to expand.

In my next article I will continue to discuss more of the anti-hypertensive meds. If you have any input I welcome your comments.

Until then, here’s to your good health.

Dr. Jon R. Link