What should you know about diuretics?

What are diuretics? Diuretics which are also known as emictory are healthcare products that helps to enforce the urine flow in kidneys. These pharmaceutical products can be divided into two main groups and few types of diuretics, they can be of natural or synthetic origin. Due to the enforced urine flow we can observe water and salts excretion, reduction liquid volume in tissues and cavities of the body, reduction of the swelling.

Diuretics are used to relief a number of various symptoms, and many people know about diuretics for the hypertension, or high blood pressure. As well they can be used to treat mild congestive heart failure, rang of liver diseases, some kinds of impaired blood circulation, since such health issues lead to liquid retention. Sometimes herbal diuretics are needed for the eliminating of bloating which is comorbid to premenstrual syndrome or can be observed during menstruation itself. Exact following instructions for the prescription of diuretics regarding method and frequency of usage will reduce greatly possibility of having strong side effects of diuretics providing certain level of safety.

Meanwhile modern gynecologists do not recommend to take diuretics during pregnancy to reduce swelling and to fight with preeclampsia, yet just decade ago there was a whole list of diuretics to treat such condition. However, later it was confirmed that taking diuretics during gestation can be harmful as for mother as fetus.

Classification of diuretics

Using diuretics for high blood pressure has started more than 50 years ago. So, what are diuretics? Or how could we define diuretics? In fact diuretics are anti hypertension products of heterogeneous class which can vary by having various targets in nephron and differences in anti hypertensive and diuretic effectiveness, the duration of action and shown metabolic effects.

Thiazide-type diuretics:

– Hydrochlorotiaside,

– Indapamide,

– Chlortalidone,

– Metazolone,

– Xipamide,

– Bendroflumetathiazide.

Loop diuretics list:

– Furosemide,

– Torasemide.

Potassium-sparing diuretics, or k-sparing diuretics:

– Aldosterone antagonist (spironolactone),

– Potassium tubular release inhibitors (triamterene, amiloride).

Diuretics and blood pressure in modern medicine are tightly linked. To treat hypertension with preserved kidneys function the low dosage of thiazide-type diuretics are common to use. Quite often they can be used as monotherapy.

Loop-type diuretics for high blood pressure is limited due to loop diuretics mechanism of action, in particular, their low anti hypertensive efficacy, and of course, due to the loop diuretics side effects, which are more frequent compare to the thiazide diuretics side effects. But on the other hand, using loop diuretics is necessary in terms of congestive heart failure and chronic renal insufficiency.

Potassium sparing diuretics possess low anti hypertensive effectiveness, therefore due to such diuretics mechanism of action they cannot be used as monotherapy for the treatment of hypertension. Usually they are combined with thiazide diuretics in order to prevent development of hypokalaemia, or hypopotassemia (especially in absence of other diuretics), and as well the treatment includes prescription of angiotensine transforming enzyme inhibitors, β-adrenoreceptor blocking agents, NSAIDs, potassic agents; such combination can be used for treating diabetes and kidney diseases, too.

Individual characteristics of diuretics action

Thiazide-type diuretics:

– Hydrochlorotiaside: May lead to the development of erectile dysfunction. Reduces potassium excretion with the urine flow, thus can be used in presence of nephrolithiasis and osteoporosis. This diuretic can reduce extraction ratio of lithium, which in turn lead to increase toxicity of lithium-containing medicine. This common diuretics may cause hyponatraemia more often than loop diuretics;

– Chlortalidone: Has longer effect compare to hydrochlortiaside, higher risk of hypomagnesaemia;

– Indapamide: This diuretics has less side effects as chlortalidone and hydrochlortiaside, the potassium loss is reduced and metabolic effects are less visible.

Loop diuretics:

– Furosemide: This loop diuretic has shorter duration of action, it has to be taken few times a day to avoid sodium retention;

Torasemide: It has longer duration of action and vasodepressing effect.

Potassium-sparing diuretics:

– Amiloride: Can lead to the development hypokaliemia, reduce potassium excretion better than hydrochlortiaside, has magnesium-saving effect, can be used to treat hypomagnaemia induced by amphotericine or platina-based medicine. It can also reduce polyuria associated with using lithium drugs;

– Spironolactone: It can be used to treat hyperaldosteronism. However its side effects include dose-related gynecomastia and longer elimination half-life, hyperpotassaemia and increased level of digoxin in blood;

– Triamterene: Can lead to the development of hyperpotassaemia, which in turn may lead to a developing triamterene kidney stones. Combination with NSAIDs will increase risk of neurotoxic effects. It also has impact on tubular secretion of creatinine (organic cation) and reduces informative value of identifying creatinine level as marker of kidneys functioning.

What do diuretics do for treating hypertension?

The best diuretics have not lesser impact to the so called hard spots compare to other anti hypertensive drugs. It has been proved that synthetic and natural diuretics for high blood pressure are more effective among elder patients compare to beta-adrenoreceptors blocking agents. So called otc, or over-the-counter, diuretics, are drugs of the first line in treating high blood pressure. According to current guidelines common diuretics are seen as starting therapy with simple hypertension without complications. Due to the high importance of BP control and reduction of cardiovascular risks metabolic effects of diuretics play key role in terms of their impact on comorbid diseases and organ protective features.