All About Diuretics
Diuretics Definition
Diuretics are medicines that help reduce the amount of water in the body.
Purpose
Diuretics are used to treat the buildup of excess fluid in the body that occurs
with some medical conditions such as congestive heart failure, liver disease,
and kidney disease. Some diuretics are also prescribed to treat high blood
pressure. These drugs act on the kidneys to increase urine output. This reduces
the amount of fluid in the bloodstream, which in turn lowers blood pressure.
Description
There are several types of diuretics, also called water pills:
???Loop diuretics, such as bumetanide (Bumex) and furosemide (Lasix), get their
name from the loop-shaped part of the kidneys where they have their effect.
???Thiazide diuretics include such commonly used diuretics as hydrochlorothiazide
(HydroDIURIL, Esidrix), chlorothiazide (Diuril), and chlorthalidone (Hygroton).
???Potassium-sparing diuretics prevent the loss of potassium, which is a problem
with other types of diuretics. Examples of potassium-sparing diuretics are
amiloride (Midamor) and triamterene (Dyrenium).
In addition, some medicines contain combinations of two diuretics. The brands
Dyazide and Maxzide, for example, contain the thiazide diuretic
hydrochlorothiazide with the potassium-sparing diuretic triamterene.
Some nonprescription (over-the-counter) medicines contain diuretics. However,
the medicines described here cannot be bought without a physician's
prescription. They are available in tablet, capsule, liquid and injectable
forms.
Recommended dosage
The recommended dosage depends on the type of diuretic and may be different for
different patients. Check with the physician who prescribed the drug or the
pharmacist who filled the prescription for the correct dosage, and take the
medicine exactly as directed.
Precautions
Seeing a physician regularly while taking a diuretic is important. The physician
will check to make sure the medicine is working as it should and will watch for
unwanted side effects.
Some people feel unusually tired when they first start taking diuretics. This
effect usually becomes less noticeable over time, as the body adjusts to the
medicine.
Because diuretics increase urine output, people who take this medicine may need
to urinate more often, even during the night. Health care professionals can help
patients schedule their doses to avoid interfering with their sleep or regular
activities.
For patients taking the kinds of diuretics that rob potassium from the body,
physicians may recommend adding potassium-rich foods or drinks, such as citrus
fruits and juices, to the diet. Or they may suggest taking a potassium
supplement or taking another medicine that keeps the body from losing too much
potassium. If the physician recommends any of these measures, be sure to closely
follow his or her directions. Do not make other diet changes without checking
with the physician. People who are taking potassium-sparing diuretics should not
add potassium to their diets, as too much potassium may be harmful.
People who take diuretics may lose too much water or potassium when they get
sick, especially if they have severe vomiting and diarrhea. They should check
with their physicians if they become ill.
These medicines make some people feel lightheaded, dizzy or faint when they get
up after sitting or lying down. Older people are especially likely to have this
problem. Drinking alcohol, exercising, standing for long periods or being in hot
weather may make the problem worse. To lessen the problem, get up gradually and
hold onto something for support if possible. Avoid drinking too much alcohol and
be careful in hot weather or when exercising or standing for a long time.
Anyone who is taking a diuretic should be sure to tell the health care
professional in charge before having surgical or dental procedures, medical
tests or emergency treatment.
Some diuretics make the skin more sensitive to sunlight. Even brief exposure to
sun can cause a severe sunburn, itching, a rash, redness, or other changes in
skin color. While being treated with this medicine, avoid being in direct
sunlight, especially between 10 a.m. and 3 p.m.; wear a hat and tightly woven
clothing that covers the arms and legs; use a sunscreen with a skin protection
factor (SPF) of at least 15; protect the lips with a sun block lipstick; and do
not use tanning beds, tanning booths, or sunlamps. People with fair skin may
need to use a sunscreen with a higher skin protection factor.
Special conditions
People who have certain medical conditions or who are taking certain other
medicines may have problems if they take diuretics. Before taking these drugs,
be sure to let the physician know about any of these conditions:
Allergies
Anyone who has had unusual reactions to diuretics or sulfonamides (sulfa drugs)
in the past should let his or her physician know before using a diuretic. The
physician should also be told about any allergies to foods, dyes, preservatives,
or other substances.
Pregnancy
Diuretics will not help the swelling of hands and feet that some women have
during pregnancy. In general, pregnant women should not use diuretics unless a
physician recommends their use. Although studies have not been done on pregnant
women, studies of laboratory animals show that some diuretics can cause harmful
effects when taken during pregnancy.
Breastfeeding
Some diuretics pass into breast milk, but no reports exist of problems in
nursing babies whose mothers use this medicine. However, thiazide diuretics may
decrease the flow of breast milk. Women who are breastfeeding and need to use a
diuretic should check with their physicians.
Other medical conditions
Side effects of some diuretics may be more likely in people who have had a
recent heart attack or who have liver disease or severe kidney disease. Other
diuretics may not work properly in people with liver disease or severe kidney
disease. Diuretics may worsen certain medical conditions, such as gout, kidney
stones, pancreatitis, lupus erythematosus and hearing problems. In addition,
people with diabetes should be aware that diuretics may increase blood sugar
levels.
People with heart or blood vessel disease should know that some diuretics
increase cholesterol or triglyceride levels. The risk of an allergic reaction to
certain diuretics is greater in people with bronchial asthma.
Before using diuretics, people with any of these medical problems should make
sure their physicians are aware of their conditions. Also, people who have
trouble urinating or who have high potassium levels in their blood may not be
able to take diuretics and should check with a physician before using them.
Use of certain medicines
Taking diuretics with certain other drugs may affect the way the drugs work or
may increase the chance of side effects.
Side effects
Some side effects, such as loss of appetite, nausea and vomiting, stomach
cramps, diarrhea and dizziness, usually lessen or go away as the body adjusts to
the medicine. These problems do not need medical attention unless they continue
or interfere with normal activities.
Patients taking potassium-sparing diuretics should know the signs of too much
potassium and should check with a physician as soon as possible if any of these
symptoms occur:
- Irregular heartbeat
- Breathing problems
- Numbness or tingling in the hands, feet or lips
- Confusion or nervousness
- Unusual tiredness or weakness
- Weak or heavy feeling in the legs.
Patients taking diuretics that cause potassium loss should know the signs of too
little potassium and should check with a physician as soon as possible if they
have any of these symptoms:
- Fast or irregular heartbeat
- Weak pulse
- Nausea or vomiting
- Dry mouth
- Excessive thirst
- Muscle cramps or pain
- Unusual tiredness or weakness
- Mental or mood changes.
Interactions
Diuretics may interact with other medicines. When this happens, the effects of
one or both of the drugs may change or the risk of side effects may be greater.
Anyone who takes a diuretic should let the physician know all other medicines he
or she is taking and should ask whether the possible interactions can interfere
with drug therapy.
Among the drugs that may interact with diuretics are:
- Angiotensin-converting enzyme (ACE) inhibitors such as benazepril (Lotensin),
captopril (Capoten) and enalapril (Vasotec), used to treat high blood pressure.
Taking these drugs with potassium-sparing diuretics may cause levels of
potassium in the blood to be too high, increasing the chance of side effects.
- Cholesterol-lowering drugs such as cholestyramine (Questran) and colestipol (Colestid).
Taking these drugs with combination diuretics such as Dyazide and Maxzide may
keep the diuretic from working. Take the diuretic at least 1 hour before or 4
hours after the cholesterol-lowering drug.
- Cyclosporine (Sandimmune), a medicine that suppresses the immune system. Taking
this medicine with potassium-sparing diuretics may increase the chance of side
effects by causing levels of potassium in the blood to be too high.
- Potassium supplements, other medicines containing potassium, or salt
substitutes that contain potassium. Taking these with potassium-sparing
diuretics may lead to too much potassium in the blood, increasing the chance of
side effects.
- Lithium, used to treat bipolar disorder (manic-depressive illness). Using this
medicine with potassium-sparing diuretics may allow lithium to build up to
poisonous levels in the body.
- Digitalis heart drugs, such as digoxin (Lanoxin). Using this medicine with
combination diuretics such as triamterene-hydrocholorthiazide (Dyazide, Maxzide)
may cause blood levels of the heart medicine to be too high, making side effects
such as changes in heartbeat more likely.
The list above does not include every drug that may interact with diuretics.
Check with a physician or pharmacist before combining diuretics with any other
prescription or nonprescription (over-the-counter) medicine.
Article by: Nancy Ross-Flanigan
Books and Courses
|
Great Websites
|
Excellent Stores
|
Recipe Cook Books
|
|
