Propranolol

Generic Name

Propranolol hydrochloride

Brand Names

Inderal

Inderal LA (long-acting)

Hemangeol (pediatric formulation)

Deralin

Dociton

Avlocardyl

Pronol

Cardinol

Avlocardyl Retard

Generic propranolol is widely available in immediate-release (IR), extended-release (ER), and oral liquid formulations

Drug Class

Non-selective beta-adrenergic blocker

Class II antiarrhythmic

Antihypertensive

Antianginal

Anxiolytic (off-label)

Migraine prophylactic

Portal antihypertensive agent

Mechanism of Action

Propranolol competitively blocks both β1 and β2 adrenergic receptors

β1 blockade leads to decreased heart rate, myocardial contractility, cardiac output, and renin release

β2 blockade causes bronchoconstriction, peripheral vasoconstriction, and reduced glycogenolysis

Its membrane-stabilizing activity at high doses contributes to antiarrhythmic effects

Propranolol crosses the blood-brain barrier and has central nervous system effects, contributing to its use in anxiety and migraine

Indications

Approved Indications

Hypertension

Angina pectoris

Cardiac arrhythmias (supraventricular tachycardia, atrial fibrillation, premature ventricular contractions)

Myocardial infarction (post-MI secondary prevention)

Migraine prophylaxis

Essential tremor

Hypertrophic subaortic stenosis

Pheochromocytoma (adjunct to alpha-blockers)

Proliferating infantile hemangioma (Hemangeol formulation)

Off-Label Uses

Generalized anxiety disorder and performance anxiety

Cirrhosis-related portal hypertension and variceal bleeding prophylaxis

Thyrotoxicosis (symptom control)

Akathisia

PTSD-related hyperarousal

Aortic dissection (rate control)

Mitral valve prolapse (symptomatic relief)

Alcohol or benzodiazepine withdrawal (adjunctive symptom control)

Dosage and Administration

Adults

Hypertension

IR: 40–80 mg twice daily

ER: 80–160 mg once daily

Max: 640 mg/day in divided doses

Angina Pectoris

IR: 80–320 mg/day in 2–4 divided doses

ER: 80–160 mg once daily

Migraine Prophylaxis

IR: Initial 40 mg twice daily

Titrate to 80–160 mg/day in divided doses

ER: 80–160 mg once daily

Arrhythmias

IR: 10–30 mg 3–4 times/day

ER: 80–160 mg once daily

Post-MI

IR: 40 mg twice daily initially

Maintenance: 180–240 mg/day in 3–4 divided doses

ER: 160 mg once daily

Essential Tremor

IR: 40 mg twice daily, up to 120–240 mg/day

Thyrotoxicosis

IR: 10–40 mg every 6–8 hours

Performance Anxiety

10–40 mg IR 30–60 minutes before performance

Pediatric

Infantile Hemangioma (Hemangeol)

Start at 0.6 mg/kg twice daily

Titrate gradually to max 3.4 mg/kg/day

Administer during or after feeding

Other pediatric uses require individualized dosing and specialist supervision

Administration Notes

Take IR tablets with or without food, consistently

Do not crush or chew ER capsules

Liquid formulation (Hemangeol) must be dosed precisely with oral syringes

Pharmacokinetics

Absorption

Rapidly absorbed orally

First-pass hepatic metabolism reduces bioavailability (~25%)

Peak plasma: 1–2 hours (IR), 6–8 hours (ER)

Distribution

Widely distributed

Crosses blood-brain barrier and placenta

~90–95% protein bound

Metabolism

Extensive hepatic metabolism via CYP2D6, CYP1A2

Primary metabolites: 4-hydroxypropranolol, naphthyloxyacetic acid

Elimination

Excreted in urine (primarily metabolites)

Half-life: 3–6 hours (IR), 8–10 hours (ER)

Prolonged in hepatic impairment

Contraindications

Sinus bradycardia

Greater than first-degree heart block (unless pacemaker present)

Overt cardiac failure or cardiogenic shock

Bronchial asthma or history of bronchospasm

Severe peripheral arterial disease

Hypersensitivity to propranolol or excipients

Warnings and Precautions

Bronchospasm

Non-selective beta-blockade can induce bronchospasm, especially in asthma or COPD

Use contraindicated in asthma

Use cardioselective beta-blockers (e.g., bisoprolol) if beta-blockade is essential in reactive airway disease

Bradycardia and AV Block

Can worsen or precipitate bradyarrhythmias

Monitor HR and ECG in at-risk patients

Masking of Hypoglycemia

May mask adrenergic symptoms of hypoglycemia (e.g., tachycardia)

Use caution in diabetics, especially insulin users

Thyrotoxicosis

Masks symptoms of hyperthyroidism

Abrupt withdrawal may precipitate thyroid storm

Peripheral Vasoconstriction

May worsen symptoms in Raynaud’s or peripheral arterial disease

CNS Effects

Fatigue, depression, nightmares, hallucinations may occur due to CNS penetration

Use caution in patients with mood disorders

Withdrawal Syndrome

Abrupt discontinuation may cause rebound hypertension, angina, or MI

Taper gradually over 1–2 weeks

Pregnancy and Lactation

Pregnancy (Category C)

Crosses placenta

May cause fetal bradycardia, growth restriction, hypoglycemia

Use only if benefits outweigh risks

Close fetal monitoring required

Lactation

Excreted in breast milk

Generally considered compatible

Monitor for bradycardia or hypoglycemia in infant

Pediatric Use

Hemangeol approved for infants with proliferating hemangioma

Use in other pediatric conditions should be guided by specialists

Geriatric Use

More sensitive to beta-blockade

Initiate at lower doses

Monitor renal and hepatic function

Adverse Effects

Very Common

Fatigue

Bradycardia

Dizziness

Cold extremities

Sleep disturbances

Common

Hypotension

Nausea

Diarrhea

Depression

Shortness of breath

Erectile dysfunction

Uncommon

Nightmares

Hallucinations

Memory impairment

AV block

Raynaud’s phenomenon

Rare but Serious

Heart failure

Bronchospasm

Severe bradycardia

Hypoglycemia

Worsening depression

Stevens-Johnson Syndrome (very rare)

Overdose

Symptoms

Severe bradycardia

Hypotension

Heart block

Bronchospasm

Seizures

Hypoglycemia

Cardiogenic shock

Management

Supportive care

IV fluids, atropine for bradycardia

Glucagon: 3–5 mg IV bolus followed by infusion

Vasopressors if needed

Beta-agonists (e.g., isoproterenol) in bronchospasm

Monitor cardiac rhythm and glucose levels

Drug Interactions

Calcium Channel Blockers (verapamil, diltiazem)

Additive risk of bradycardia and heart block

Avoid concomitant IV administration

Antiarrhythmics (amiodarone, digoxin)

Increased risk of bradyarrhythmias

Monitor ECG

CYP2D6 Inhibitors (fluoxetine, paroxetine, quinidine)

Increase plasma concentration of propranolol

Dose adjustment may be required

NSAIDs

Reduce antihypertensive effect

Monitor BP with concurrent use

Insulin and oral hypoglycemics

Mask symptoms of hypoglycemia

Enhance hypoglycemic effect

Clonidine

Abrupt discontinuation of clonidine with propranolol can cause rebound hypertension

Taper propranolol before stopping clonidine

Epinephrine (e.g., in anaphylaxis)

Beta-blockade may blunt response to epinephrine

Use glucagon if epinephrine ineffective

Alcohol

Can increase plasma levels of propranolol and CNS depression

Use in Special Populations

Renal Impairment

No major adjustment needed

Monitor for drug accumulation

Hepatic Impairment

Reduced clearance

Lower starting doses recommended

Monitoring Parameters

Blood pressure and heart rate (baseline, then periodically)

ECG in arrhythmia patients

Blood glucose in diabetic patients

Signs of worsening heart failure

Mood and sleep disturbance in long-term use

Signs of bronchospasm or peripheral ischemia

Comparative Pharmacology

Propranolol vs Atenolol

Propranolol is non-selective, lipophilic (more CNS side effects)

Atenolol is cardioselective (β1), hydrophilic, longer half-life

Propranolol vs Metoprolol

Propranolol: non-selective, better for essential tremor, migraines

Metoprolol: β1-selective, better in heart failure or asthma patients

Propranolol vs Nadolol

Both non-selective

Nadolol has longer half-life, less CNS penetration

Formulations Available

Immediate-release tablets: 10 mg, 20 mg, 40 mg, 60 mg, 80 mg

Extended-release capsules: 60 mg, 80 mg, 120 mg, 160 mg

Oral solution (Hemangeol): 4.28 mg/mL

IV injection (in hospital settings for arrhythmias)

Regulatory and Legal Status

Approved worldwide

Prescription-only

Essential medicine (WHO Model List)

Listed in BNF, FDA Orange Book, and MIMS