Beta-blockers are used in the treatment of abnormal heart rhythms, congestive heart failure, high blood pressure and chest pain, according to the Texas Heart Institute. For people with a history of heart attack, beta-blockers are also used to prevent additional heart attacks.
Beta-blockers change the way adrenaline works on beta receptors in the body, slowing down the electrical signals that control a person's heartbeat. As a result, the heart needs less oxygen and blood, so it does not have to pump as hard. Beta-blockers also block the electrical impulses responsible for arrhythmia, notes the Texas Heart Institute.
Medications classified as beta-blockers include atenolol, metoprolol, propranolol and bisoprolol. Dizziness, trouble sleeping and feeling tired are the most common side effects of beta-blockers, reports WebMD. In people with diabetes, beta-blockers may cause elevated blood sugar levels. This type of medication also increases sensitivity to sunlight and cold in some people.
Some side effects of beta-blockers are less common. They include slow heartbeat, vivid dreams, wheezing, swelling of the hands or feet, shortness of breath and difficulty breathing, reports the Texas Heart Institute. There have also been reports of rare side effects such as abdominal cramps, constipation, diarrhea, sore throat, joint pain, back pain, impotence, skin rash, confusion and memory loss.