This belongs to the group of medicines known as beta-blockers.
Lopressor can be used to treat high blood pressure, angina (chest pain), irregular heartbeat and to control some symptoms associated with an overactive thyroid problem. It can also be used to prevent migraines occurring.

High Blood Pressure: Lopressor works by blocking the transmission of messages to the beta receptors in the heart which slows down the activity of the heart decreasing blood pressure.

Angina: Lopressor works by blocking the transmission of messages to the beta receptors in the heart which slows down the activity of the heart and reduces the heart's need for oxygen. This makes angina attacks less likely to occur.

Irregular Heartbeat: Normally the heartbeat is regulated by special tissues which conduct electricity. Some cases of irregular heartbeat are caused by these tissues conducting electricity too quickly. Lopressor works by reducing over-activity in the conducting tissue.

Thyroid Problems: An overactive thyroid gland causes symptoms such as a fast or pounding heartbeat, trembling and sweating. Blocking beta receptors relieves these symptoms quickly, as anti-thyroid treatment usually takes several weeks to take effect.

Migraine: The pain of a migraine attack is usually due to widening of the blood vessels on the surface of the brain. Lopressor prevents this widening and thus prevents attacks.

Lopressor is available in tablet and injection form. Lopressor is also available in modified release form, which means Lopressor is released slowly over the day to give an even effect.

It is also sometimes known as: Betaloc; Lopresor. You may notice the use of any of these names on the packaging of your medicine.