For a patient with uncontrolled hypertension on atenolol (beta blocker) 25mg daily, is it better to increase the frequency to twice daily or increase the dose to 50mg daily?

Management of Acutely Uncontrolled Hypertension on Atenolol

For a patient with acutely uncontrolled hypertension on atenolol 25mg daily (BPs 170-190/111-123), increasing the dose to 50mg once daily is more appropriate than increasing the frequency to twice daily.

Rationale for Dose Increase vs. Frequency Change

Pharmacokinetics and FDA Guidance

• The FDA label for atenolol clearly indicates that the standard approach for hypertension management is to increase the dose from 25mg to 50mg once daily before considering other adjustments 1
• Atenolol has a long half-life that supports once-daily dosing, particularly in patients with normal renal function 1
• The full effect of a dose adjustment is typically seen within 1-2 weeks 1

Evidence for Once-Daily Dosing

• Research has demonstrated that once-daily administration of atenolol provides equivalent blood pressure control to twice-daily dosing of the same total daily dose 2
• The 2020 International Society of Hypertension guidelines recommend simplifying antihypertensive regimens with once-daily dosing to improve adherence 3

Dose Titration Algorithm

1. Current status: Patient on atenolol 25mg daily with BP 170-190/111-123
2. Next step: Increase to atenolol 50mg once daily
3. Monitoring: Reassess BP within 1-2 weeks to evaluate response
4. If inadequate response: Consider further dose increase to 100mg once daily
5. If still inadequate: Add a second agent from a different class (e.g., thiazide diuretic, calcium channel blocker)

Important Considerations

Severity Assessment

• The patient's current BP readings (170-190/111-123) indicate Grade 2 hypertension with significant elevation of both systolic and diastolic pressures 3
• This level of uncontrolled hypertension requires prompt intervention to reduce cardiovascular risk

Dosing Principles

• The ISH 2020 guidelines recommend increasing to full dose of the initial agent before adding additional medications 3
• For beta-blockers like atenolol, increasing to full dose (which can be up to 100mg daily) is appropriate before considering alternative regimens 3

Monitoring

• Target BP reduction should be at least 20/10 mmHg, ideally to <140/90 mmHg 3
• BP control should be achieved within 3 months 3
• Monitor for potential side effects including bradycardia and hypotension 3

Potential Pitfalls

1. Renal function: Atenolol is excreted by the kidneys. If the patient has renal impairment (creatinine clearance <35 mL/min), dose adjustment may be needed 1

2. Abrupt discontinuation: Never abruptly stop beta-blocker therapy as this can lead to rebound hypertension 1

3. Contraindications: Ensure patient has no contraindications to increased beta-blocker dosing (e.g., severe bradycardia, heart block, decompensated heart failure, asthma) 3

4. Elderly patients: Dose selection should be cautious in elderly patients, though the standard approach of increasing from 25mg to 50mg daily remains appropriate unless renal function is impaired 1

By following this approach of increasing the once-daily dose rather than splitting the dose, you optimize both efficacy and adherence while following established guidelines for beta-blocker titration in hypertension management.