Precautions and Warnings With Propranolol
Specific precautions and warnings with propranolol to be aware of include:
- Propranolol can interact with certain medications (see Drug Interactions With Propranolol).
- Serious allergic reactions have occurred in people taking propranolol. Make sure to discuss this risk with your healthcare provider. Also, seek emergency medical attention immediately if you notice things such as hives, an unexplained rash or peeling of the skin, difficulty breathing, wheezing, or swelling of the face or throat.
- Propranolol may hide certain signs of hyperthyroidism. Do not stop taking propranolol suddenly, as this can cause serious symptoms. Make sure to talk with your healthcare provider before stopping propranolol so that it can be done in a safe manner.
- Propranolol may cause extreme low blood pressure and/or a slow heart rate in some people. Symptoms can include dizziness, lightheadedness, and fainting. If you develop any of these symptoms, contact your healthcare provider. Extreme low blood pressure is more likely to occur in people who are taking a diuretic, who are on dialysis, or who have diarrhea or vomiting. Also, make sure not to drive, operate any heavy machinery, or perform any other tasks that require alertness before you know how propranolol affects you.
- People who have severe congestive heart failure and are taking propranolol are at an increased risk of making their heart failure worse. Therefore, if your healthcare provider prescribes propranolol, it is because he or she believes that the benefits of the drug outweigh the potential risks. He or she may choose to monitor your situation more closely if this is the case.
- Using beta blockers, such as propranolol, for a long period of time can, in some cases, lead to heart failure, particularly in people with a history of heart failure. If you notice unexplained weight gain; swelling of the ankles, feet, or legs; cough; and shortness of breath, contact your healthcare provider immediately (see Symptoms of Congestive Heart Failure).
- People taking propranolol should not stop it abruptly. In clinical studies, this has been shown to increase a person's chances of developing angina (chest pain), heart attack, or serious irregular heart rhythms (arrhythmias). This risk is even greater in people with existing heart disease.
- Low blood sugar levels have been reported in people taking propranolol. This has been more common in infants, children, and people with kidney disease, as well as in those who are fasting before surgery or after prolonged exercise. Low blood sugar symptoms may include irritability, trembling, cold sweats, or blurry vision, among other things (see Inderal and Low Blood Sugar).
- If you have kidney disease or kidney failure, your body may metabolize the propranolol differently than intended. Therefore, your healthcare provider may choose to monitor your situation more closely.
- Beta blockers, including propranolol, are used with caution, if at all, in people with certain lung diseases, such as asthma, emphysema, chronic bronchitis, or chronic obstructive pulmonary disease (COPD). This is because beta blockers affect the lungs and can cause a narrowing of the airways. This risk is greater in people with certain lung diseases. If you develop problems with breathing or wheezing, call your healthcare provider.
- For people with allergies, taking propranolol may increase the reaction to the specific allergens, and the body may not respond to the usual doses of epinephrine.
- Propranolol may lower the pressure within the eye (intraocular pressure). This can affect the results of the glaucoma screening test. Stopping propranolol will usually increase the intraocular pressure again.
- If you are going to have surgery, let your healthcare provider or dentist know that you are taking propranolol.
- Propranolol is a pregnancy Category C medicine, meaning that there may be an increased risk to the fetus. Let your healthcare provider know if you are pregnant or thinking of becoming pregnant. If you become pregnant while taking propranolol, contact your healthcare provider (see Inderal and Pregnancy).
- It is known that propranolol passes through breast milk. Therefore, if you are breastfeeding, be sure to check with your healthcare provider before taking propranolol (see Propranolol and Breastfeeding).