Penbutolol

Penbutolol

Chemical structure of Penbutolol

Penbutolol is a non-selective beta blocker used in the management of hypertension and angina pectoris. It is known for its ability to reduce blood pressure and heart rate by blocking the action of epinephrine and norepinephrine on beta-adrenergic receptors.

Pharmacology

Penbutolol is a beta-adrenergic antagonist that exhibits partial agonist activity. This means that while it primarily acts as a blocker, it can also slightly stimulate beta receptors, which can be beneficial in certain clinical situations. The drug is lipophilic, allowing it to cross the blood-brain barrier, which may contribute to its central nervous system effects.

Mechanism of Action

Penbutolol works by blocking beta-1 and beta-2 adrenergic receptors. By inhibiting these receptors, it decreases the effects of sympathetic nervous system stimulation, leading to a reduction in heart rate, cardiac output, and blood pressure. This makes it effective in treating conditions like hypertension and angina.

Clinical Uses

Penbutolol is primarily used for:

• Hypertension: It helps in lowering high blood pressure, reducing the risk of stroke and myocardial infarction.
• Angina pectoris: It alleviates chest pain by reducing the heart's demand for oxygen.

Side Effects

Common side effects of penbutolol include:

• Fatigue
• Dizziness
• Nausea
• Bradycardia

Less common but serious side effects can include:

• Bronchospasm
• Heart failure
• Depression

Contraindications

Penbutolol should not be used in patients with:

• Asthma or chronic obstructive pulmonary disease (COPD)
• Severe bradycardia
• Heart block

Administration

Penbutolol is administered orally, typically once daily. The dosage may vary based on the patient's condition and response to the medication.

Related pages

• Beta blocker
• Hypertension
• Angina pectoris
• Adrenergic receptor