Can candesartan (Angiotensin II receptor antagonist) be prescribed twice daily (BID) in an elderly patient with hypertension and elevated evening blood pressure?

Can Candesartan Be Prescribed BID in an 82-Year-Old with Evening Hypertension?

Yes, candesartan can be prescribed twice daily (BID) in this 82-year-old patient, as the FDA label explicitly states that "candesartan cilexetil can be administered once or twice daily with total daily doses ranging from 8 mg to 32 mg." 1

FDA-Approved Dosing Flexibility

• The FDA label for candesartan clearly permits BID dosing across the entire therapeutic range (8-32 mg total daily dose), providing flexibility for patients who may benefit from split dosing 1
• For elderly patients specifically, no initial dosage adjustment is necessary, though the pharmacokinetics show approximately 50% higher Cmax and 80% higher AUC compared to younger patients 1
• The elimination half-life of candesartan is approximately 9 hours, which supports the pharmacologic rationale for BID dosing if once-daily dosing fails to provide 24-hour control 1

Clinical Rationale for BID Dosing in Evening Hypertension

• If this patient has adequate morning blood pressure control but elevated evening readings on once-daily dosing, splitting the total daily dose into BID administration is a reasonable strategy 1
• Research demonstrates that candesartan has a trough-to-peak ratio close to 1.0 with once-daily dosing, suggesting excellent 24-hour coverage 2, but individual patients may still experience end-of-dose waning
• The drug binds tightly to and dissociates slowly from the AT1 receptor, providing long-lasting suppression of the renin-angiotensin system 2

Practical Dosing Algorithm for This Patient

• Start by confirming the current total daily dose is optimized (up to 32 mg daily maximum) 1
• If the patient is on candesartan 16 mg once daily with evening hypertension, consider either:
  • Increasing to 32 mg once daily first, OR
  • Splitting to 8 mg BID (morning and evening)
• If already on 32 mg once daily with inadequate evening control, split to 16 mg BID 1
• Reassess blood pressure control within 4 weeks, as maximal antihypertensive effect occurs within this timeframe 1

Special Considerations for This 82-Year-Old Patient

• European Society of Cardiology guidelines emphasize that initial doses and subsequent titration should be more gradual in elderly patients due to greater chance of undesirable effects 3
• Blood pressure should be measured in both sitting and standing positions due to increased risk of postural hypotension in the elderly 3
• The SCOPE trial specifically demonstrated stroke reduction in hypertensive patients aged 70 years or older treated with candesartan-containing regimens 3
• For patients aged 80 years and over, there is no reason to interrupt successful and well-tolerated therapy 3

Alternative Strategies Before BID Dosing

• Consider adding a thiazide or thiazide-like diuretic (chlorthalidone or indapamide) or a dihydropyridine calcium channel blocker (amlodipine) rather than splitting candesartan to BID 4, 5
• Many elderly patients need two or more drugs to control blood pressure, and combination therapy may be more effective than dose manipulation alone 3
• If evening hypertension persists despite optimization, consider chronotherapy (timing the dose in the evening rather than morning) before splitting to BID

Monitoring Requirements

• Recheck blood pressure within 2-4 weeks of any dosing change 5
• Monitor serum potassium and renal function, especially in elderly patients, as candesartan can affect these parameters 4
• Target blood pressure goal is <140/90 mmHg if tolerated in this elderly patient 3, 5
• Confirm control with home blood pressure monitoring (target <135/85 mmHg) 4

Key Clinical Caveat

The most important consideration is that BID dosing is FDA-approved and safe, but adding a second antihypertensive agent from a different class may provide superior blood pressure control compared to simply splitting the candesartan dose 4, 5. The decision should be based on whether the patient has already maximized the candesartan dose and whether monotherapy or combination therapy is more appropriate for achieving the blood pressure target.