Description

Atenolol is a beta-blocker medication that is commonly used to treat cardiovascular conditions. It is specifically a cardioselective beta-blocker, meaning it primarily targets and blocks receptors in the heart. The maleate salt form is used to improve the drug’s stability and bioavailability for oral administration.

Indications

Atenolol is prescribed for several conditions, often used alone or in combination with other drugs. Its main indications include:

• Hypertension (High Blood Pressure): It lowers blood pressure, reducing the strain on the heart and arteries.
• Angina Pectoris (Chest Pain): It helps prevent chest pain associated with heart disease.
• Acute Myocardial Infarction (Heart Attack): It is used to improve survival and reduce the risk of a second heart attack after a patient has experienced one.
• Other Uses (Off-label): It can also be used to treat certain irregular heart rhythms, prevent migraine headaches, and manage symptoms of anxiety or alcohol withdrawal.

Mechanism of Action

Atenolol’s therapeutic effects are a result of its ability to block β1-adrenergic receptors. Here’s how it works:

1. Selective Receptor Blockade: Atenolol selectively binds to beta-1 adrenergic receptors, which are found in high concentrations in the heart. This prevents the natural stress hormones, like epinephrine (adrenaline) and norepinephrine, from binding to these receptors.
2. Decreased Heart Rate and Contractility: By blocking the beta-1 receptors, atenolol inhibits the stimulating effects of these hormones on the heart. This leads to a decrease in heart rate and the force of heart muscle contractions.
3. Reduced Blood Pressure: The slower heart rate and reduced force of contractions lead to a decrease in cardiac output. This, in turn, lowers blood pressure and reduces the workload on the heart. The effect of atenolol on blood pressure is also linked to its ability to inhibit the release of renin from the kidneys.
4. Improved Oxygen Supply: For conditions like angina, the reduced workload on the heart means it requires less oxygen, which helps relieve chest pain.