From the Guidelines
Propranolol is a non-cardioselective beta-blocker medication used to treat various conditions, including high blood pressure, irregular heartbeat, angina, essential tremor, and anxiety, with a typical starting dose of 80-160mg daily, as indicated in the 2018 guideline 1. The medication works by blocking beta-adrenergic receptors, primarily in the heart, which reduces heart rate and blood pressure by preventing the effects of adrenaline.
- Key characteristics of propranolol include:
- Non-cardioselective beta-blocker
- Available in immediate release (IR) and long-acting (LA) formulations
- Typical starting dose: 80-160mg daily, divided into 2 doses for IR or 1 dose for LA
- Common side effects: fatigue, dizziness, and cold extremities
- Contraindications: certain heart conditions like heart block or severe bradycardia, asthma, and uncontrolled heart failure
- Should not be stopped abruptly to avoid rebound effects, as suggested by the 2013 guideline 1. According to the 2018 guideline 1, propranolol is not recommended as a first-line agent for hypertension unless the patient has specific conditions such as ischemic heart disease or heart failure.
- The choice of beta-blocker, including propranolol, should be based on pharmacokinetic and side effect criteria, as well as physician familiarity, as stated in the 2013 guideline 1. In terms of dosing, the 2013 guideline 1 provides a range of 20 to 80 mg twice daily for propranolol in the context of angina, but the 2018 guideline 1 suggests a higher dose range of 80-160mg daily for general use. Overall, propranolol is a valuable medication for managing various cardiovascular and other conditions, but its use should be tailored to individual patient needs and monitored closely for potential side effects and interactions.
From the FDA Drug Label
Propranolol is a nonselective, beta-adrenergic receptor-blocking agent possessing no other autonomic nervous system activity. It specifically competes with beta-adrenergic receptor-stimulating agents for available receptor sites When access to beta-receptor sites is blocked by propranolol, the chronotropic, inotropic, and vasodilator responses to beta-adrenergic stimulation are decreased proportionately.
Propranolol is a beta blocker that works by blocking the effects of beta-adrenergic stimulation, resulting in decreased heart rate, contractility, and vasodilation.
- Key effects: decreased chronotropic, inotropic, and vasodilator responses
- Mechanism of action: competes with beta-adrenergic receptor-stimulating agents for available receptor sites
- Result: decreased cardiac output, inhibition of renin release, and diminution of tonic sympathetic nerve outflow from vasomotor centers in the brain 2
From the Research
Definition and Mechanism of Propranolol
- Propranolol is a non-cardioselective β1,2 blocker, meaning it blocks both beta-1 and beta-2 adrenergic receptors 3.
- It is commonly used to treat various cardiovascular conditions, such as hypertension, coronary artery disease, and tachyarrhythmias 3.
- Propranolol's ability to cross the blood-brain barrier and its affinity for multiple macromolecules make it useful for treating anxiety and stress-related conditions, including stage fright and post-traumatic stress disorder (PTSD) 3.
Pharmacological Properties and Clinical Use
- Propranolol has been shown to be effective in preventing cardiovascular complications in hypertension mega-trials, along with other beta-blockers like atenolol, metoprolol, and oxprenolol 4.
- It is often used to treat diseases comorbid with hypertension, making it a relevant first-choice treatment in clinical practice, particularly for patients with elevated heart rates 4.
- Propranolol's hypotensive effect can take six to eight weeks to reach its maximum, and it is contraindicated in patients with obstructive airways disease or uncompensated heart failure 5.
Comparison with Other Beta-Blockers
- Propranolol is a non-selective beta-blocker, whereas other beta-blockers like bisoprolol and metoprolol are more selective for beta-1 receptors 6, 7.
- The choice of beta-blocker is important, as benefit is not a class-effect, and some beta-blockers (e.g., xamoterol, bucindolol, nebivolol) may have diminished efficacy due to intrinsic sympathomimetic activity (ISA) 6.
- Propranolol's lipophilic properties allow it to appear in high concentrations in human brain tissue, which can lead to side effects like insomnia, dreams, and nightmares 6.