What is the appropriate dosage and treatment regimen for Inderal (propranolol) in a patient with hypertension, angina, or migraines?

Inderal (Propranolol) Dosing and Treatment Guidelines

Hypertension Management

For hypertension, start propranolol extended-release at 80 mg once daily and titrate to 120-160 mg once daily for adequate blood pressure control, with a maximum dose of 640 mg daily if needed. 1

Initial Dosing Strategy

• Begin with propranolol hydrochloride extended-release capsules 80 mg once daily, whether used alone or combined with a diuretic 1
• The usual maintenance dosage is 120-160 mg once daily 1
• In some instances, dosages up to 640 mg may be required for adequate blood pressure control 1

Important Titration Considerations

• The time needed for full hypertensive response to a given dosage is variable and may range from a few days to several weeks 1
• Retitration may be necessary when switching from immediate-release tablets to extended-release capsules, as they have different kinetics and produce lower blood levels 1
• Extended-release capsules should not be considered a simple mg-for-mg substitute for immediate-release tablets 1

Target Blood Pressure Goals

• For patients with stable angina and hypertension, target BP <140/90 mmHg (Class I, Level of Evidence A) 2
• A lower target BP (<130/80 mmHg) may be considered in select patients with CAD, previous stroke/TIA, or CAD risk equivalents 2

Combination Therapy Recommendations

• Beta-blockers like propranolol should be combined with ACE inhibitors or ARBs and thiazide diuretics for patients with hypertension and coronary artery disease 2, 3
• This triple combination (beta-blocker + ACE inhibitor/ARB + thiazide diuretic) is recommended even in the absence of prior MI, LV dysfunction, diabetes, or proteinuric CKD (Class IIa, Level of Evidence B) 2
• Beta-blockers are particularly indicated in patients with prior MI for secondary prevention 2, 3

Angina Pectoris Management

For angina, start propranolol extended-release at 80 mg once daily and gradually increase at 3-7 day intervals until optimal response is obtained, with an average optimal dosage of 160 mg once daily. 1

Dosing Protocol

• Initial dose: 80 mg propranolol extended-release once daily 1
• Average optimal dose: 160 mg once daily 1
• Maximum studied dose: 320 mg per day (safety and efficacy beyond this dose not established) 1
• Increase dosage gradually at 3-7 day intervals until optimal response is achieved 1

Clinical Evidence

• Propranolol 100 mg three times daily was more effective than placebo in reducing angina episodes and prolonging total exercise time in stable angina patients 1
• Extended-release propranolol 160 mg daily was as effective as conventional propranolol 40 mg four times daily for exercise tolerance, ST-segment depression, angina attack rate, and nitroglycerin consumption 1

Discontinuation Protocol

• If treatment must be discontinued, reduce dosage gradually over a period of a few weeks to avoid rebound angina 1
• Abrupt discontinuation can cause severe exacerbation of angina, myocardial infarction, and ventricular arrhythmias 4

Role in Comprehensive Angina Management

• Beta-blockers, CCBs, and nitrates are the mainstays of angina treatment 2
• Long-acting nitrates or CCBs can be prescribed when beta-blockers are contraindicated or cause unacceptable side effects (Class I, Level of Evidence B) 2
• Long-acting nitrates or CCBs in combination with beta-blockers should be prescribed when initial beta-blocker therapy is unsuccessful (Class I, Level of Evidence B) 2

Migraine Prophylaxis

For migraine prevention, start propranolol extended-release at 80 mg once daily and increase gradually to the usual effective dose range of 160-240 mg once daily. 1

Dosing Guidelines

• Initial dose: 80 mg propranolol extended-release once daily 1
• Usual effective dose range: 160-240 mg once daily 1
• Increase dosage gradually to achieve optimal migraine prophylaxis 1

Treatment Duration and Discontinuation

• If satisfactory response is not obtained within 4-6 weeks after reaching maximal dose, discontinue propranolol therapy 1
• Withdraw the drug gradually over several weeks, considering the patient's age, comorbidity, and dose 1

Clinical Evidence

• In a 34-week placebo-controlled study, propranolol 20-80 mg 3-4 times daily significantly reduced the headache unit index (composite of headache days and severity) compared to placebo 1

Important Drug Interaction

• Rizatriptan (Maxalt) is contraindicated with propranolol (Inderal) due to drug interactions 2
• When using triptans for acute migraine treatment in patients on propranolol, avoid rizatriptan and select alternative triptans 2

Hypertrophic Subaortic Stenosis

For hypertrophic subaortic stenosis, the usual dosage is 80-160 mg propranolol extended-release once daily. 1

Clinical Evidence

• In an uncontrolled series of 13 patients with NYHA class 2-3 symptoms, oral propranolol 40-80 mg three times daily was associated with improved NYHA class for most patients over 17 months of follow-up 1

Critical Safety Considerations and Contraindications

Absolute Contraindications

• Signs of heart failure, low output state, or decompensated heart failure 4
• Second or third-degree heart block without a functioning pacemaker 4
• Active asthma or severe reactive airway disease 4
• Cardiogenic shock 4

Monitoring Parameters

• Monitor blood pressure and heart rate at each visit, especially after dose adjustments 3
• Watch for symptomatic bradycardia (heart rate <60 bpm with dizziness or lightheadedness) 4
• Assess for hypotension (systolic BP <100 mmHg with symptoms like dizziness, lightheadedness, or blurred vision) 4
• Monitor for signs of worsening heart failure or bronchospasm 4

Special Populations

• Pregnancy: Propranolol requires caution, though it is considered safer than ACE inhibitors which are contraindicated 3
• Elderly patients: May achieve therapeutic effects at lower doses due to higher plasma levels compared to younger patients 5

Common Pitfalls to Avoid

• Never abruptly discontinue propranolol, as this can cause severe exacerbation of angina, myocardial infarction, ventricular arrhythmias, and increased mortality risk 4
• Do not assume extended-release and immediate-release formulations are interchangeable on a mg-for-mg basis—they have different pharmacokinetics 1
• Do not combine propranolol with rizatriptan for migraine patients, as this combination is contraindicated 2
• Do not use propranolol as monotherapy for hypertension when compelling indications exist for combination therapy (CAD, post-MI, diabetes, CKD) 2, 3
• Do not administer to patients with decompensated heart failure or active asthma without first stabilizing these conditions 4