- High Blood Pressure Slideshow Pictures
- Take the Salt Quiz!
- Lowering Blood Pressure Exercise Tips Pictures
What are thiazide diuretics, and how do they work?
Thiazide diuretics (water pills) are medications that are used to treat high blood pressure (hypertension) and reduce fluid accumulation in the body. They work by reducing the ability of the kidneys to reabsorb salt and water from the urine and into the body thereby increasing the production and output of urine (diuresis).
For what conditions are thiazide diuretics used?
Thiazide diuretics are used to treat high blood pressure and congestive heart failure as well as the accumulation of fluid and swelling (edema) of the body caused by conditions such as heart failure, cirrhosis, chronic kidney failure, corticosteroid medications, and nephrotic syndrome.
What are the side effects of thiazide diuretics?
Side effects of thiazide diuretics are dose related and include:
- dizziness and lightheadedness,
- blurred vision,
- loss of appetite,
- stomach upset,
- headache, and
Other side effects and adverse reactions are:
- An increased sensitivity to sunlight (prolonged sun exposure should be avoided)
- Owing to their ability to increase the production of urine, these drugs may lower levels in the body of potassium and magnesium which also are present in urine.
- Thiazide diuretics may increase uric acid levels in blood.
- Like other antihypertensive medications, thiazides cause sexual dysfunction.
Are there any differences among the thiazide diuretics?
Thiazide diuretics are similar in effectiveness and usually are not effective in people with severe renal impairment.
With which drugs do thiazide diuretics interact?
Thiazide diuretics can lower potassium and magnesium blood levels since they are both eliminated in urine. Low levels of potassium and magnesium in the blood can result in abnormal heart rhythms, particularly in those who are also taking digoxin (Lanoxin) in addition to a thiazide. Thiazide diuretics can increase the risk of lithium (Eskalith, Lithobid) toxicity by reducing the kidney's ability to eliminate lithium in the urine.
Drugs known as nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin), naproxen (Naprosyn), and nabumetone (Relafen) can reduce the effectiveness of thiazide diuretics in lowering blood pressure because they may reduce the ability of the kidneys to make urine, particularly in patients who have reduced kidney function.
It is not recommended to use thiazide diuretics with dofetilide (Tikosyn), a drug used for treating abnormal heart rhythms, as this may increase the blood levels of dofetilide (Tikosyn) and cause abnormal heart rhythms. Thiazide diuretics can reduce how the body responds to norepinephrine and render norepinephrine less effective.
Quick GuideHow to Lower Blood Pressure: Exercise Tips
Multimedia: Slideshows, Images & Quizzes
High Blood Pressure (Hypertension) Quiz: Symptoms, Signs & Causes
Take this quiz and test your IQ of high blood pressure (hypertension), the cardiovascular disease that causes most strokes and...
High Blood Pressure (Hypertension): Symptoms, Causes, Treatments
What causes high blood pressure (hypertension)? Know the warning signs and symptoms of high blood pressure. Read about high blood...
Foot Health: Causes of Swollen Feet and Ankles
Swollen feet and ankles may be associated with conditions like pregnancy, injury, heart failure, kidney disease, liver disease,...
Related Disease Conditions
Cirrhosis of the liver refers to a disease in which normal liver cells are replaced by scar tissue caused by alcohol and viral...
High Blood Pressure (Hypertension) Signs, Causes, Diet, and Treatment
High blood pressure (hypertension) is a disease in which pressure within the arteries of the body is elevated. About 75 million...
12 Congestive Heart Failure Symptoms, Stages, Causes, and Life Expectancy
Congestive heart failure (CHF) refers to a condition in which the heart loses the ability to function properly. Heart disease,...
Kidney Failure (Symptoms, Signs, Stages, Causes, Treatment, and Life Expectancy)
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss,...
Edema is the swelling of tissues as a result of excess water accumulation. Peripheral edema occurs in the feet and legs. There...
High Blood Pressure Treatment (Natural Home Remedies, Diet, Medications)
High blood pressure (hypertension) means high pressure (tension) in the arteries. Treatment for high blood pressure include...
Treatment & Diagnosis
Medications & Supplements
Prevention & Wellness
Heart Health Resources
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.