- What is captopril, and how does it work (mechanism of action)?
- What brand names are available for captopril?
- Is captopril available as a generic drug?
- Do I need a prescription for captopril?
- What are the side effects of captopril?
- What is the dosage for captopril?
- Which drugs or supplements interact with captopril?
- Is captopril safe to take if I'm pregnant or breastfeeding?
- What else should I know about captopril?
What is captopril, and how does it work (mechanism of action)?
Captopril is an oral drug and a member of a class of drugs called angiotensin converting enzyme (ACE) inhibitors. ACE inhibitors are used for treating high blood pressure, heart failure, and for preventing kidney failure due to high blood pressure and diabetes. Other ACE inhibitors include enalapril (Vasotec), quinapril (Accupril), ramipril (Altace), fosinopril (Monopril), benazepril (Lotensin), lisinopril (Zestril, Prinivil), moexipril (Univasc) and trandolapril (Mavik).
Angiotensin II is a very potent chemical that causes the muscles surrounding blood vessels to contract, thereby narrowing the vessels. The narrowing of the vessels increases the pressure within the vessels causing high blood pressure (hypertension). Angiotensin II is formed from angiotensin I in the blood by the enzyme angiotensin converting enzyme or ACE. ACE inhibitors are medications that slow (inhibit) the activity of the enzyme ACE and decrease the production of angiotensin II. As a result, blood vessels enlarge or dilate, and blood pressure is reduced. The lower blood pressure makes it easier for the heart to pump blood and can improve the function of a failing heart. In addition, progression of the disease in the blood vessels within the kidney caused by high blood pressure or diabetes is slowed. The FDA approved captopril in April 1981.
What are the side effects of captopril?
Captopril generally is well tolerated, and side effects are usually mild and transient. A dry, persistent cough has been reported commonly with the use of captopril and other ACE inhibitors. Coughing resolves after discontinuing the drug. Other side effects include abdominal pain, constipation, diarrhea, rash, dizziness, fatigue, headache, loss of taste, loss of appetite, nausea, vomiting, fainting and numbness or tingling in the hands or feet.
Captopril and other ACE inhibitors also may cause kidney failure and increased levels of potassium in the blood. Serious but, fortunately, very rare side effects are liver failure and angioedema (swelling of lips and throat that can obstruct breathing).
What is the dosage for captopril?
- The recommended dose of captopril for treating hypertension in adults is 25-150 mg two or three times daily.
- The maximum dose is 450 mg daily. The dose for treating heart failure is 6.25 to 12.5 mg every 8 hours.
- The target dose is 50 mg every 8 hours and the maximum dose is 450 mg daily.
- The dose for diabetic nephropathy is 25 mg every 8 hours.
- It should be taken on an empty stomach one hour before or two hours after meals since absorption of captopril is reduced when it is taken with food.
Which drugs or supplements interact with captopril?
: The use of ACE inhibitors with potassium supplements, salt substitutes or diuretics, for example, spironolactone (Aldactone), that increase potassium in the blood may lead to excessive potassium levels (hyperkalemia). Potassium levels should be monitored whenever ACE inhibitors are used in combination with these drugs.
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 antiinflammatory 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 are usually reversible.
Nitritoid reactions (symptoms include facial flushing, nausea, vomiting and low blood pressure) may occur when injectable gold (sodium aurothiomalate), used in the treatment of rheumatoid arthritis, is combined with ACE inhibitors, including captopril.
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Is captopril safe to take if I'm pregnant or breastfeeding?
Captopril is secreted in breast milk. Therefore it should be avoided by nursing mothers.
Captopril (Capoten) is an ACE inhibitor prescribed for the treatment of high blood pressure, heart failure, and prevention of kidney failure due to high blood pressure and diabetes. Side effects, drug interactions, warnings and precautions, and efficacy during pregnancy information should be reviewed prior to taking this medication.
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Related Disease Conditions
High Blood Pressure (Hypertension)
High blood pressure (hypertension) is a disease in which pressure within the arteries of the body is elevated. About 75 million people in the US have hypertension (1 in 3 adults), and only half of them are able to manage it. Many people do not know that they have high blood pressure because it often has no has no warning signs or symptoms. Systolic and diastolic are the two readings in which blood pressure is measured. The American College of Cardiology released new guidelines for high blood pressure in 2017. The guidelines now state that blood normal blood pressure is 120/80 mmHg. If either one of those numbers is higher, you have high blood pressure. The American Academy of Cardiology defines high blood pressure slightly differently. The AAC considers 130/80 mm Hg. or greater (either number) stage 1 hypertension. Stage 2 hypertension is considered 140/90 mm Hg. or greater. If you have high blood pressure you are at risk of developing life threatening diseases like stroke and heart attack.REFERENCE: CDC. High Blood Pressure. Updated: Nov 13, 2017.
Kidney (Renal) Failure
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss, dehydration, or medication. Some of the renal causes of kidney failure include sepsis, medications, rhabdomyolysis, multiple myeloma, and acute glomerulonephritis. Post renal causes of kidney failure include bladder obstruction, prostate problems, tumors, or kidney stones.Treatment options included diet, medications, or dialysis.
Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
Congestive Heart Failure (CHF)
Congestive heart failure (CHF) refers to a condition in which the heart loses the ability to function properly. Heart disease, high blood pressure, diabetes, myocarditis, and cardiomyopathies are just a few potential causes of congestive heart failure. Signs and symptoms of congestive heart failure may include fatigue, breathlessness, palpitations, angina, and edema. Physical examination, patient history, blood tests, and imaging tests are used to diagnose congestive heart failure. Treatment of heart failure consists of lifestyle modification and taking medications to decrease fluid in the body and ease the strain on the heart. The prognosis of a patient with congestive heart failure depends on the stage of the heart failure and the overall condition of the individual.
Pulmonary edema, or fluid in the lungs, can cause symptoms such as shortness of breath. Learn about causes, diagnosis complications, treatment, and prevention.
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Things to Know About High Blood Pressure Treatment
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Renal Artery Stenosis
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Heart Attack Treatment
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Heart Attack Prevention
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Medications & Supplements
- ACE Inhibitors
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- Drug Interactions
- Types of High Blood Pressure Medications
- lisinopril (Zestril, Prinivil, Qbrelis) ACE Inhibitor
- Congestive Heart Failure Medications
- ramipril (Altace)
- trandolapril (Mavik)
- benazepril (Lotensin HTC)
- enalapril (Vasotec, Epaned)
- lisinopril and hydrochlorothiazide (Zestoretic, Prinzide)
- quinapril (Accupril)
- benazepril and hydrochlorothiazide (Lotensin HCT)
- fosinopril sodium, Monopril
- captopril and hydrochlorothiazide (Capozide)
- Side Effects of Capoten (captopril)
- enalapril and hydrochlorothiazide (Vaseretic)
- Side Effects of Capozide (captopril and hydrochlorothiazide/HCTZ)
Prevention & Wellness
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