Propranolol

Propranolol is a beta blocker and was developed in the 1960s. Its development was honored with the Nobel Prize in Medicine in 1988. Propranolol non-selectively blocks both beta-1 and beta-2 receptors.

In addition to high blood pressure, propranolol is used for numerous other conditions: migraine prevention, essential tremor, anxiety disorders with physical symptoms (stage fright), hyperthyroidism, and infantile hemangiomas. Well-known products are Propra-ratiopharm® and Obsidan®.

Because propranolol is not cardioselective, it is prescribed less often today for high blood pressure alone than bisoprolol or metoprolol. However, its versatility still makes it an important medication.

Propranolol non-selectively blocks beta-1 and beta-2 receptors:

Beta-1 blockade (heart):

• Lowers heart rate and blood pressure
• Reduces the heart's oxygen consumption
• Inhibits renin release

Beta-2 blockade (lungs, blood vessels, metabolism):

• Can narrow the bronchi (caution: asthma)
• Can worsen peripheral circulation
• Affects glucose and fat metabolism
• Inhibits glycogenolysis in the liver

Special properties:

• Lipophilic – crosses the blood-brain barrier well
• Central effect (migraine prevention, tremor treatment, anxiety relief)
• Membrane-stabilizing effect
• Inhibits the conversion of T4 to T3 (useful in hyperthyroidism)

Onset of action: Rapid onset of action after 1-2 hours. Half-life of 3-6 hours, so it needs to be taken several times a day (except the extended-release form).

Propranolol is suitable for:

• Adults with high blood pressure
• Migraine prevention
• Essential tremor
• Hyperthyroidism (symptom control)
• Situational anxiety / stage fright
• Angina pectoris
• After a heart attack

Particularly suitable for:

• Migraine (well documented)
• Tremor
• Overactive thyroid
• Anxiety with physical symptoms (palpitations, sweating, trembling)

Not suitable for:

• Bronchial asthma (strictly contraindicated!)
• Severe COPD
• Second- or third-degree AV block
• Severe bradycardia
• Decompensated heart failure
• Prinzmetal angina

High blood pressure:

• Starting dose: 40 mg twice daily
• Usual dose: 80-160 mg daily (divided into 2-3 doses)
• Maximum dose: 320 mg daily
• Extended-release form: 80-160 mg once daily

Migraine prevention:

• 40-80 mg two to three times daily
• Gradual dose increase over 2-3 weeks

Essential tremor:

• 40 mg two to three times daily
• Increase up to 120-240 mg daily

Stage fright (situational):

• 10-40 mg about 30-60 minutes before the situation

Available strengths:

• 10 mg, 40 mg, 80 mg tablets
• 80 mg, 160 mg extended-release capsules

How to take (standard form):

• Two to three times daily
• Before meals (more even absorption)
• Take with water

How to take (extended-release form):

• Once daily
• Do not open or chew the capsules
• Regardless of meals

Important notes:

• Never stop abruptly (taper off slowly over 1-2 weeks)
• Regular pulse and blood pressure checks
• In people with diabetes: monitor blood sugar closely
• Do not take if you have asthma
• Inform the anesthesiologist before surgery

Propranolol must not be taken in cases of:

• Bronchial asthma (strictly contraindicated!)
• Severe COPD with bronchospasm
• Second- or third-degree AV block
• Sick sinus syndrome
• Severe bradycardia (below 50/min)
• Cardiogenic shock
• Severe hypotension
• Untreated pheochromocytoma
• Metabolic acidosis
• Prinzmetal angina
• Severe peripheral circulatory disorders

Caution in cases of:

• Diabetes mellitus (strong masking of hypoglycemia symptoms)
• Mild COPD
• Psoriasis
• Myasthenia gravis
• Severe renal impairment

Pregnancy: Only if strictly indicated. May cause bradycardia and hypoglycemia in the newborn.

Common (1-10%):

• Tiredness, exhaustion
• Cold hands and feet (more pronounced than with selective beta blockers)
• Bradycardia
• Gastrointestinal complaints
• Sleep disturbances, vivid dreams

Uncommon (0.1-1%):

• Depressed mood
• Erectile dysfunction
• Bronchospasm
• Dizziness
• Weight gain
• Worsening of glucose and fat metabolism

Rare:

• Raynaud's syndrome (white fingers)
• Hallucinations
• Worsening of psoriasis
• Alopecia (hair loss)

Important: Because propranolol also blocks beta-2 receptors, side effects such as cold extremities, bronchospasm, and metabolic changes occur more often than with cardioselective beta blockers.

Contraindicated with:

• Verapamil or diltiazem IV
• MAO inhibitors (exception: MAO-B inhibitors)

Caution with:

• Insulin and oral antidiabetic drugs → strong masking of hypoglycemia
• Epinephrine → paradoxical rise in blood pressure and bradycardia
• Clonidine → worsened rebound hypertension after stopping clonidine (first stop propranolol gradually, then reduce clonidine step by step only a few days later)
• Ergotamine preparations → increased vasoconstriction
• Rifampicin → accelerated breakdown of propranolol
• Cimetidine → increased propranolol levels
• CYP1A2 and CYP2D6 inhibitors → increased levels

Food: Protein-rich meals can increase the bioavailability of propranolol. Grapefruit juice can also slightly increase levels.