captopril and hydrochlorothiazide (Capozide)

Capozide is a combination of captopril (Capoten) and hydrochlorothiazide (HCTZ), an angiotensin converting enzyme (ACE) inhibitor and a diuretic (water pill), respectively, and is used in the treatment of high blood pressure. ACE is an enzyme in the body that causes the formation of angiotensin II. Angiotensin II causes the arteries in the body to narrow, thereby elevating blood pressure. ACE inhibitors, such as captopril, lower blood pressure by preventing the formation of angiotensin II thereby relaxing the arteries. HCTZ is a diuretic (water pill) used for treating high blood pressure (hypertension) and accumulation of fluid. It works by blocking salt and fluid reabsorption in the kidneys, causing increased urine output (diuresis). The mechanism of its action in lowering high blood pressure is not well understood. The combination of captopril and HCTZ reduces blood pressure better than either drug alone. Captopril increases potassium levels while HCTZ reduces potassium levels; the combination of both drugs has less effect on potassium levels. The FDA approved captopril/HCTZ in October 1984.

What brand names are available for captopril and hydrochlorothiazide?

Capozide

Is captopril and hydrochlorothiazide available as a generic drug?

Yes

Do I need a prescription for captopril and hydrochlorothiazide?

Yes

A dry, persistent cough has been reported commonly with the use of ACE inhibitors. Coughing resolves after discontinuing the drug.

Other common side effects include:

• diarrhea,
• rash,
• itching,
• dizziness,
• loss of taste,
• weight loss,
• low blood pressure, and
• sexual dysfunction.

Increased blood glucose and potassium levels also may occur.

Serious but, fortunately, very rare side effects are liver failure angioedema (swelling of lips and throat that can obstruct breathing).

Capozide may reduce kidney function in some patients and should not be used by patients who have bilateral renal artery stenosis (narrowing of both arteries going to the kidneys).

Rare cases of rhabdomyolysis (muscle breakdown), reduced number of platelets, and pancreatitis have been reported.

The starting dose is 25/15 mg once daily. The dose may be increased every 6 weeks.

Captopril may increase potassium levels (hyperkalemia) in blood. Therefore, there is an increased risk of hyperkalemia when captopril is given with potassium supplements or drugs that increase potassium levels (for example, spironolactone [Aldactone]).

There have been reports of increased lithium (Eskalith, Lithobid) levels when lithium is used in combination with ACE inhibitors. The reason for this interaction is not known, but the increased levels may lead to toxicity from lithium.

There have been reports that aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Children's Advil/Motrin, Medipren, Motrin, Nuprin, PediaCare Fever, etc.), indomethacin (Indocin, Indocin-SR), and naproxen (Anaprox, Naprelan, Naprosyn, Aleve) may reduce the effects of ACE inhibitors.

Combining captopril or other ACE inhibitors with nonsteroidal anti-inflammatory drugs (NSAIDs) in patients who are elderly, volume-depleted (including those on diuretic therapy), or with poor kidney function may result in reduced kidney function, including kidney failure. These effects usually are reversible.

Nitritoid reactions (symptoms include facial flushing, nausea, vomiting and hypotension or low blood pressure) may occur when injectable gold (sodium aurothiomalate), used in the treatment of rheumatoid arthritis, is combined with ACE inhibitors, including captopril. 

Hydrochlorothiazide reduces the elimination of lithium (Lithobid) by the kidneys and can lead to lithium toxicity. Nonsteroidal antiinflammatory drugs, for example, ibuprofen, may reduce the blood pressure lowering effects of hydrochlorothiazide. Blood sugar levels can be elevated by HCTZ, necessitating adjustment in the doses of medications that are used for treating diabetes. Combining HCTZ with corticosteroids may increase the risk for low levels of blood potassium and other electrolytes. Low blood potassium can increase the toxicity of digoxin (Lanoxin). Cholestyramine (Questran, Questran Light) and colestipol (Colestid) bind to hydrochlorothiazide and reduce its absorption from the gastrointestinal tract by 43%-85%.

When used in the second or third trimester of pregnancy ACE inhibitors can cause injury and even death to the fetus. Capozide should not be used during pregnancy.

Both captopril and HCTZ are excreted in breast milk and may potentially affect nursing infants.

What preparations of captopril and hydrochlorothiazide are available?

Tablets (captopril/HCTZ): 25/15, 25/25, 50/15, and 50/25 mg.

How should I keep captopril and hydrochlorothiazide stored?

Tablets should be stored at room temperature, 15 C - 30 C (59 F - 86 F).