Diuretics, Thiazide (Systemic)

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For thiazide diuretics, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to sulfonamides (sulfa drugs), bumetanide, furosemide, acetazolamide, dichlorphenamide, methazolamide, or to any of the thiazide diuretics. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy - When this medicine is used during pregnancy, it may cause side effects including jaundice, blood problems, and low potassium in the newborn infant. In addition, although this medicine has not been shown to cause birth defects or other problems in animals, studies have not been done in humans.

In general, diuretics are not useful for normal swelling of feet and hands that occurs during pregnancy. They should not be taken during pregnancy unless recommended by your doctor.

Breast-feeding - Thiazide diuretics pass into breast milk. These medicines also may decrease the flow of breast milk. Therefore, you should avoid use of thiazide diuretics during the first month of breast-feeding.

Children - Although there is no specific information comparing the use of thiazide diuretics in children with use in other age groups, these medicines are not expected to cause different side effects or problems in children than they do in adults. However, extra caution may be necessary in infants with jaundice, because these medicines can make the condition worse.

Older adults - Dizziness or lightheadedness and signs of too much potassium loss may be more likely to occur in the elderly, who are more sensitive than younger adults to the effects of thiazide diuretics.

Other medicines - Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking thiazide diuretics, it is especially important that your health care professional know if you are taking any of the following:

• Cholestyramine or
• Colestipol - Use with thiazide diuretics may prevent the diuretic from working properly; take the diuretic at least 1 hour before or 4 hours after cholestyramine or colestipol

• Digitalis glycosides (heart medicine) - Use with thiazide diuretics may cause high blood levels of digoxin, which may increase the chance of side effects

• Lithium (e.g., Lithane) - Use with thiazide diuretics may cause high blood levels of lithium, which may increase the chance of side effects

Other medical problems - The presence of other medical problems may affect the use of thiazide diuretics. Make sure you tell your doctor if you have any other medical problems, especially:

• Diabetes mellitus (sugar diabetes) - Thiazide diuretics may increase the amount of sugar in the blood

• Gout (history of) or
• Lupus erythematosus (history of) or
• Pancreatitis (inflammation of the pancreas) - Thiazide diuretics may make these conditions worse

• Heart or blood vessel disease - Thiazide diuretics may cause high cholesterol levels or high triglyceride levels

• Liver disease or
• Kidney disease (severe) - Higher blood levels of the thiazide diuretic may occur, which may prevent the thiazide diuretic from working properly