Patients should consult their physicians before taking any other medication (either prescription or over-the-counter), nutritional supplements or herbal remedies. Of particular concern for individuals taking beta blockers are:

• Antiarrhythmics or antihypertensives (drugs that slow heart rate or lower blood pressure) such as calcium channel blockers or ACE inhibitors. Combined, these medications may lower blood pressure to unsafe levels. However, lower doses of these medications are routinely prescribed along with beta blockers in patients who do not respond to other therapies. Some medications even combine more than one antihypertensive into a single pill.
  
  
• Antacids containing aluminum. These may reduce the absorption and, therefore, the effectiveness of beta blockers. Patients should consult their physicians before using these substances.
  
  
• Alcohol. May reduce the absorption and, therefore, the effectiveness of beta blockers. Patients should consult their physicians about how much alcohol is safe to drink while on beta blockers.
  
  
• Caffeine. May reduce the effects of beta blockers. Patients should consult their physicians about how much caffeine is safe to drink while on beta blockers.
  
  
• Insulin and other antidiabetic drugs. Taking beta blockers may result in the need to adjust the dosages of these antidiabetic drugs because of their effect on glucose metabolism (low blood sugar) in diabetic patients.
  
  
• Monoamine oxidase inhibitors (MAO-Is). Taking beta blockers within two weeks of an MAO-I can result in severe high blood pressure (hypertension). Patients should inform physicians of all medications they are currently taking, or have recently been taking, before filling their beta blocker prescription.
  
  
• Allergy shots or skin tests. Combination with beta blockers may produce severe allergic reactions.
  
  
• Nonsteroidal anti-inflammatory drugs (NSAIDs). These drugs (e.g., aspirin and ibuprofen) can decrease the effectiveness of the beta blockers.
  
  
• Bronchodilators. Medications to treat asthma, bronchitis, emphysema or other lung diseases.

In some cases, physicians will prescribe other medications in combination with beta blockers, such as diuretics (medications that reduce the amount of fluid retained in the body by increasing urine flow). Because diuretics and beta blockers are often prescribed together to treat high blood pressure, they are sometimes available in a single combination pill. The generic names of these combination pills will contain the names of both medications. For example “bisoprolol hydrochlorothiazide” is a single tablet containing both bisoprolol (a beta blocker) and hydrochlorothiazide (a thiazide diuretic).