Types of Medications | What They Are Prescribed For | How Diuretics Work | Precautions While Taking a Diuretic | Dosing and Missed Doses | Possible Side Effects

Types of Medications

There are different types of diuretics (water pills) that are used to treat many health conditions. These include:

  • Loop diuretics
  • Potassium-sparing diuretics
  • Thiazide diuretics
  • Potassium-sparing and hydrochlorothiazide combination

What They Are Prescribed For

Diuretics may be prescribed to treat:

  • High blood pressure —sustained high force of blood flow against artery walls
  • Heart failure —inadequate circulation causes swelling resulting from fluid build-up
  • Lymphedema —inadequate lymph circulation causes swelling resulting from fluid build-up
  • Hypercalcemia—excess calcium levels in the blood
  • Hirsutism —excess hair growth in women that appears in places similar to men
  • Diabetes insipidus —water in the body is improperly removed from the circulatory system by the kidneys

How Diuretics Work

Diuretics act on the kidneys to increase the production of urine. Unlike other types, potassium-sparing diuretics do not cause your body to lose potassium.

Precautions While Taking a Diuretic

It is important that your doctor checks your progress at regular visits to allow for dosage adjustments and to manage any side effects. Before you have any type of surgery, including dental surgery, emergency treatment, or medical tests, make sure the doctor or dentist knows that you are taking a diuretic.

Thiazide diuretics, and especially loop diuretics, may cause an excessive loss of potassium from your body. To help prevent this, your doctor may recommend that you:

  • Choose foods and drinks that are high in potassium. Potassium is found in many foods, especially fruits and vegetables. Examples include dried figs, avocados, potatoes, bananas, oranges, and raisins.
  • Take a potassium supplement.
  • Take another diuretic or medication to help prevent the loss of potassium.

To prevent the loss of too much water and potassium, tell your doctor if you become sick, especially with severe or continuing vomiting or diarrhea.

Do not make any dietary changes, even if you are on a special diet, without talking to your doctor first. Some diuretics do not cause potassium loss and may not require any dietary adjustment.

Diuretics are generally not useful for treating the normal swelling of hands and feet that can occur with pregnancy. Diuretics should not be taken during pregnancy unless recommended by your doctor. You also need to be cautious about taking medication when you are breastfeeding. Diuretics are not recommended for nursing mothers.

Tell your doctor about all of the medications that you take. Some should not be taken with diuretics, while others may require a different dosage level. If you are taking any type of diuretic to control high blood pressure, check with your doctor before taking any over-the-counter medications, including those to treat colds, cough, and allergies.

The presence of other conditions may affect the use of diuretics. Tell your doctor if you have any other conditions, especially diabetes, kidney, liver, heart, and autoimmune disorders.

Medications are only part of the treatment for high blood pressure. Research has shown that you can help control your blood pressure by eating a low-sodium diet that is rich in fruits, vegetables, and low-fat dairy. Exercising regularly and maintaining a healthy weight are also essential lifestyle factors to manage high blood pressure.

When you are taking a diuretic, you may have dizziness, or lightheadedness that can lead to fainting. This may happen when you get up from a lying or sitting position. Getting up slowly may help. These symptoms are also more likely to occur if you drink alcohol, stand for long periods of time, exercise vigorously, or if the weather is hot. If the problem continues or worsens, tell your doctor.

Some diuretics may cause your skin to be more sensitive to sunlight. Exposure to sunlight, even for brief periods of time, may cause a rash, itching, redness, or sunburn. If you have skin problems because of the sun, follow these precautions:

  • Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m.
  • Wear protective clothing, including a hat and sunglasses.
  • Apply sunscreen and sunblock lip balm with an SPF of at least 30.
  • Do not use a sunlamp or tanning bed or booth.
  • If you have a severe reaction from the sun, tell your doctor.

It is essential to take your medication even if you feel fine and do not have any symptoms, which is often the case with high blood pressure. You must continue to take the medication as directed in order to keep your blood pressure under control. It may be possible to taper off the medication, particularly if you make lifestyle changes, such as diet and exercise, recommended by your doctor. If high blood pressure persists without treatment, it can lead to heart attacks, heart failure, blood vessel diseases, stroke, kidney failure, and/or blindness.

Dosing and Missed Doses

Take each dose at the same time each day. Since diuretics work by increasing the amount of urine you produce, try to take your medication early in the day so that your need to urinate will not disrupt your sleep.

  • If you take a single dose, take it after breakfast.
  • If you take more than one dose, take the last dose no later than 6:00 p.m., unless otherwise directed by your doctor.

If the diuretic upsets your stomach, it may be taken with food or drink. If stomach upset continues or gets worse, or if you suddenly get severe diarrhea, tell your doctor.

If you miss a dose, take it as soon as possible. But if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Possible Side Effects

The side effects listed here are most commonly encountered with at least one type of diuretic drug, not necessarily all of them. Many of the effects of diuretics are similar, these side affects may occur with any one of these medications, although they may be more common with some more than with others. Side effects may be more prevalent in the elderly.

Side effects may include:

Diuretics are generally well tolerated by most people. If you are having problems with side effects talk to your doctor. You may be able to get your dose adjusted or try a different medication.