How to manage elevated blood pressure in a patient already taking lisinopril 20 mg daily?

Management of Elevated Blood Pressure Despite Lisinopril 20 mg Daily

For a patient with elevated blood pressure despite lisinopril 20 mg daily, add a calcium channel blocker (such as amlodipine 5-10 mg daily) as the next step in therapy, followed by a thiazide-like diuretic if needed for further control. 1

Assessment of Current Regimen

Before adding new medications, evaluate:

• Medication adherence to current regimen
• Proper BP measurement technique (validated device, appropriate cuff size)
• Confirm hypertension with home or ambulatory BP monitoring if office readings are elevated
• Review lifestyle factors (sodium intake, physical activity, alcohol consumption)

Stepped Care Approach for Non-Black Patients

According to the 2020 International Society of Hypertension guidelines, the recommended approach for managing uncontrolled hypertension in a patient already on an ACE inhibitor (lisinopril) is:

1. First step (current): ACE inhibitor (lisinopril 20 mg daily)
2. Second step: Add a dihydropyridine calcium channel blocker (DHP-CCB) such as amlodipine 5-10 mg daily
3. Third step: Add a thiazide/thiazide-like diuretic (e.g., chlorthalidone 12.5-25 mg or indapamide 1.25-2.5 mg daily)
4. Fourth step: Add spironolactone 25-50 mg daily (if renal function and potassium are normal)

If BP remains uncontrolled after these steps, consider referral to a hypertension specialist 1.

Evidence Supporting This Approach

The FDA label for lisinopril indicates that while it is effective as monotherapy in many patients, some will require additional medications for adequate BP control 2. Studies have shown that lisinopril at doses of 20-80 mg daily is effective for hypertension, but combination therapy may be needed for optimal control.

Research specifically examining patients not controlled on the combination of amlodipine and lisinopril found that adding a thiazide diuretic (bendrofluazide) was more effective than adding a beta-blocker (atenolol) 3. This supports the recommended sequence of adding a CCB followed by a thiazide diuretic.

Target Blood Pressure

• The general target BP is <130/80 mmHg 1
• Aim to reduce BP by at least 20/10 mmHg from baseline 1
• BP control should be achieved within 3 months 1

Important Considerations

• Medication interactions: Review potential interactions with the patient's other medications (clonazepam, clopidogrel, aspirin, ezetimibe, buspirone, finasteride, metformin, silodosin)
• Comorbidities: Diabetes (present given metformin use) supports the lower BP target of <130/80 mmHg
• Monitoring: Once a new medication is added, reassess BP after 2-4 weeks

Common Pitfalls to Avoid

1. Inadequate dosing: Ensure lisinopril is at optimal dose before adding other agents
2. Overlooking adherence: Non-adherence is a common cause of apparent treatment resistance
3. White coat hypertension: Confirm elevated readings with home or ambulatory monitoring
4. Suboptimal combinations: Avoid using clonidine as it has been associated with increased mortality in heart failure patients 1
5. Ignoring secondary causes: Consider screening for secondary hypertension if BP remains difficult to control despite multiple medications

Special Circumstances

If the patient is of Black African descent, the recommended approach differs:

• Consider a CCB or thiazide diuretic as first-line therapy
• ARBs may be more effective than ACE inhibitors in this population 1

If resistant hypertension develops (BP uncontrolled on ≥3 medications including a diuretic), consider adding spironolactone if renal function is adequate and potassium is <4.5 mmol/L 1.