Beta Blockers

Beta blockers are a group of medications that are typically used to treat hypertension and heart disease but have also occasionally been abused by athletes to gain a competitive advantage. If a medication name ends in “-lol,” such as atenolol or carvedilol, it is usually an indication that the medication is in the beta blocker family.

Beta blockers are antagonists (blockers) to beta-1 (and to a lesser degree beta-2) receptors. Stimulation of beta-1 receptors increases the heart rate, and therefore, taking beta blockers will slow the heart rate. In the body, chemicals such as epinephrine (adrenaline) will increase the heart rate in response to fear or excitement or with activity such as exercise by stimulating beta-1 receptors in the heart. Beta blockers are typically used to treat high blood pressure or irregular heartbeats. They have been used for a long time and have saved many lives, especially after someone has had a heart attack.

Beta blockers can also minimize tremors. For this reason, people have used them to control symptoms of stage fright or before public speaking. This is also one of the reasons why they are banned in certain types of athletic competition, such as biathlons. Biathletes have to run or ski to certain checkpoints. They then must shoot targets, sometimes with an air rifle or pistol or with archery. Beta blockers give an advantage by controlling the heart rate and tremors, making it easier to take a steady shot after running or skiing. Athletes who do artistic performances, such as ice skaters, gymnasts, or dancers, may be tempted to use beta blockers to minimize the physical signs of stress and to project confidence.

Common side effects of beta blocker use include dizziness, fatigue, or syncope (passing out). They are especially dangerous in athletes who use them for performance enhancement rather than to treat a medical condition. Exercise increases the need for oxygen, and the heart beats faster to get oxygenated blood to the tissues that need it. If the heart rate is artificially limited, dangerous drops in blood pressure can occur. In addition, beta blockers can induce arrhythmias (erratic and sometimes deadly heart rhythms). Nonselective beta blockers may also induce asthma symptoms since there is a beta receptor in the lung (beta-2 receptor) that needs to be stimulated to keep the airways open. Blocking these receptors causes the tiny muscles around the airway to constrict.