Diuretics refer to foods or medications that promote removal of excess water and salt (sodium) from your body, in the form of urine. If required, doctors prescribe specific medicines that act as diuretics and help lose excess water from your body. These medications are generally referred to as 'water pills'. These are usually administered to treat heart failure, high blood pressure, liver cirrhosis, certain kidney diseases, glaucoma, and edema (accumulation of fluids in one's tissues).

How Diuretics Work
Under certain conditions, when the kidneys are not be able to work properly, they may absorb larger amounts of water and salts back into the bloodstream during the process of blood purification. This creates problems for the heart as it has to pump a larger volume of blood through the body. Besides, the excess amount of water may leak into other organs of the body causing other health problems. Diuretics reduce the amount of water and salt that the kidneys reabsorb into the bloodstream. Hence, more water and salts are lost from the body. This prevents the problem of water logging of the tissues and improves the functioning of the heart.

Common Side Effects of Diuretics
Taking diuretics is considered as safe; but like other medications, they also come with certain side effects. The side effects are a result of the change in the amount of levels of minerals in the body. Some of the most common effects are listed below.
  • Increased urination
  • Electrolyte disturbance
  • Headache
  • Muscle cramps
  • Increased thirst
  • Irregular menstruation
  • High blood sugar levels
  • Low blood sodium levels
  • Abnormal heart rhythm
  • Weakness, Extreme tiredness / Fatigue
  • Dizziness, Lightheadedness
  • Skin rash
  • Loss of appetite
  • Nausea
  • They may interfere with your routine medication. So, you should inform your physician about the prescribed and non-prescribed medication that you are likely to take and should follow the instructions of your physician religiously.
Sometimes, diuretics can lead to 'enlargement of breasts (gynecomastia)' in men.

Types of Diuretics
The following are the major types:
  • Thiazides, Examples: Indapamide, Chlorothiazide
  • Loop diuretics, Examples: Bumetanide, Furosemide (Lasix)
  • Potassium sparing diuretics, Examples: Amiloride, Spironolactone (Aldactone). These are used more often in the treatment of congestive heart failure.
Some pills may contain combinations of the different types. Vegetables like asparagus, tomatoes and oats are examples of natural diuretic foods.

Thiazide Diuretics
  • As the body tries to adjust to the medication, the initial side effects of thiazide diuretics may reflect as loss of appetite, itching, blurred vision, headache, stomach upset and weakness.
  • Some individuals even feel dizzy and light-headed during the first few days. To minimize such a feeling, if you are lying or sleeping and want to get up and move around, rise slowly.
  • In case one develops side effects like nausea, vomiting, trouble breathing or muscle cramps, the physician should be contacted immediately.
  • Some may even have allergic reactions to thiazide diuretics. Such reactions may manifest as rash, itching, dizziness and difficulty in breathing.
  • Excessive use of these pills may result in low blood potassium levels, impaired glucose tolerance, high serum cholesterol, and elevated serum uric acid levels.
  • Those who have gout may have more gout attacks after taking them.
  • They are known for a weak action on the kidneys. So, urine output is not drastically increased (as with loop diuretics).
  • Moreover, they lead to dilation of blood vessels. This may eventually lead to low blood pressure.
  • Some patients experience increased sensitivity to sunlight, impotence, as side effects; but these problems often disappear on stopping the treatment.
Loop Diuretics
  • Loop diuretics are used in the treatment of heart failure and certain liver and kidney disorders. Fluid accumulation in lungs often leads to difficulty in breathing. These pills help get rid of the excess fluid.
  • The first time an individual takes a loop diuretic, he may need to pass a large volume of urine which may require him to make regular trips to the washroom. This effect may be felt within an hour of having taken it, and may last up to 6 hours.
  • The most common side effect is dizziness or lightheadedness, specially when one tries to get up from a sitting or lying position.
  • They may cause a change in the levels of potassium and other electrolytes in the blood. If one feels excessive thirst, dry mouth, decrease in urination, drowsiness and lethargy, one should get his blood tested for reduced levels of potassium which is a condition medically known as hypokalemia.
  • Some may experience increase in the uric acid and sugar levels in blood.
  • In some cases, they may cause a decrease in the amount of magnesium in the blood.
  • They may lead to high calcium levels, and low sodium and potassium levels.
  • The less common side effects include loss of appetite, diarrhea, nausea, vomiting, fatigue, confusion, temporary loss of hearing, jaundice, irregular heartbeats, male impotence, certain blood disorders leading to weak immune system and acute gout attacks.
Potassium Sparing Diuretics
  • Consumption of these diuretics can result in high blood potassium levels in people who already have a high potassium level or who have kidney disease.
  • Although this does away with the possibility of low levels of this mineral in a patient's body, one should be aware of the symptoms of high level of potassium in the body, like irregular heartbeat, confusion or numbness, unusual tiredness, weakness or a heavy feeling in the legs, confusion or nervousness and breathing problems.
Those who have diabetes or gout need to take extra care while taking diuretics, otherwise they may experience worsening of the condition. Pregnant and lactating women should use them only if clearly needed and under the supervision of the doctor. Another aspect to be taken into consideration is that many patients taking diuretics develop a resistance to them. So, consulting a physician before and after taking diuretics; and monitoring the effectiveness of the diuretics is very important. Patients who take higher doses are at a greater risk of developing the side-effects. Older patients are more likely to suffer from the side effects and may require close observation. The doctor may lower their doses after knowing about the symptoms of the side effects.

Disclaimer: This Buzzle article is for informative purposes only, and should not be used as a replacement for expert medical advice.