Warnings and Precautions With Captopril
Some captopril warnings and precautions to be aware of include:
- There are several medicines that captopril can interact with (see Drug Interactions With Captopril).
- ACE inhibitors are more likely than other drugs to cause allergic reactions. For example, there have been reports of severe allergic reactions occurring in people on captopril during dialysis. There have also been reports of severe reactions in people getting bee or wasp venom to protect against stings. Seek emergency medical attention immediately if you notice things such as hives, an unexplained rash, difficulty breathing, or swelling of the face or throat.
- ACE inhibitors may cause swelling (angioedema) of the head and neck, including the tongue, lips, eyes, or throat. This occurs more frequently in African Americans. Seek emergency medical care immediately if you notice swelling in the head or neck area or if you have wheezing, difficulty breathing, or swallowing.
- In addition to head and neck angioedema, ACE inhibitors have also been known to cause swelling in the intestines. This is known as intestinal angioedema. Symptoms may include stomach pain, with or without vomiting. Seek medical attention immediately if you develop any of these symptoms.
- Captopril may cause extreme low blood pressure in some people. This is more likely to happen in people who are taking a diuretic, who are on dialysis, who have diarrhea or vomiting, or who sweat a lot. This is why it is important to drink fluids regularly while taking captopril. If you have any possible symptoms of low blood pressure, such as dizziness, lightheadedness, or fainting, contact your healthcare provider and stop taking the medicine. Also, make sure not to drive, operate any heavy machinery, or perform any other tasks that require alertness before you know how captopril affects you.
- People on captopril can be at increased risk for infections because the drug may decrease the levels of blood cells used to fight infections. This is more common in people with certain diseases, like scleroderma, lupus, or kidney failure or in people taking immunosuppressants. Talk to your healthcare provider if you develop any infections, such as a sore throat or fever.
- Captopril is considered a pregnancy Category D medicine, meaning that it has health risks to your unborn child. Let your healthcare provider know if you are pregnant or thinking of becoming pregnant. If you become pregnant while taking captopril, contact your healthcare provider immediately (see Captopril and Pregnancy).
- ACE inhibitors, including captopril, are known to cause a cough. If a cough becomes bothersome, talk to your healthcare provider about alternate options for your condition (see Captopril Cough).
- While taking captopril, do not use potassium supplements or salt substitutes with potassium unless you have discussed this with your doctor. This is because in some people taking captopril, potassium in the blood can increase to dangerous levels.
- If you are over 65 years old, your healthcare provider may choose to make any necessary dosing adjustments with caution.
- This medication may cause a decrease in kidney function, especially in people who are elderly, have kidney disease, have severe congestive heart failure (CHF), or are taking nonsteroidal anti-inflammatory drugs (NSAIDs) or diuretics (water pills). Your healthcare provider may choose to monitor your kidney function with a blood test while you are taking it.
Contact your healthcare provider if you notice a decrease in urination or swelling in your hands, legs, ankles, or feet, which can be signs of kidney problems.
- If you have kidney disease or kidney failure, your body may metabolize the captopril differently than intended. Therefore, your healthcare provider will likely monitor your situation more closely if this is the case.
- In clinical studies, ACE inhibitors, including captopril, have rarely been known to cause liver failure. Contact your healthcare provider immediately if you notice things such as nausea, tiredness, lethargy, itchy or yellowing skin, abdominal pain, or flu-like symptoms.
- If you are nursing, it is not known whether captopril passes through your milk. Therefore, if you are nursing, talk with your healthcare provider about whether you should discontinue captopril or stop breastfeeding.