What antihypertensive medication should be adjusted for a patient with uncontrolled hypertension on metoprolol succinate (Metoprolol), amlodipine (Amlodipine), hydrochlorothiazide (Hydrochlorothiazide), and lisinopril (Lisinopril)?

Management of Uncontrolled Hypertension in a Patient on Multiple Antihypertensives

For a 40-year-old patient with uncontrolled hypertension (130/92 mmHg) despite being on four antihypertensive medications, adding spironolactone 25mg daily as a fifth agent is the most effective next step in management. 1

Current Medication Analysis

The patient is currently on:

• Metoprolol succinate 100 mg daily (beta-blocker)
• Amlodipine 10 mg daily (calcium channel blocker)
• Hydrochlorothiazide 12.5 mg daily (thiazide diuretic)
• Lisinopril 40 mg daily (ACE inhibitor)

This regimen includes medications from four major antihypertensive classes, with the patient already at maximum dose of amlodipine and a high dose of lisinopril.

Recommended Medication Adjustment

Primary Recommendation

• Add spironolactone 25mg daily as the most effective fourth-line agent for resistant hypertension 1
  • Despite the patient already being on four medications, their blood pressure remains uncontrolled (130/92 mmHg)
  • The diastolic reading of 92 mmHg is still above the target of <90 mmHg
  • Spironolactone has been shown to be particularly effective in resistant hypertension cases

Monitoring Requirements

• Check renal function and electrolytes within 1-2 weeks after adding spironolactone
• Pay special attention to potassium levels due to the combination of spironolactone with an ACE inhibitor (lisinopril) 1
• Once stable, monitor every 1-3 months

Alternative Considerations

If spironolactone is contraindicated or not tolerated:

1. Increase hydrochlorothiazide dose

   • Current dose (12.5mg) is relatively low
   • Could increase to 25mg daily if renal function permits

2. Consider medication adherence

   • Non-adherence is a common cause of resistant hypertension 2
   • Simplifying the regimen to once-daily dosing when possible can improve adherence 1

Target Blood Pressure

• For a 40-year-old patient, the target blood pressure should be <130/80 mmHg 1
• Current reading of 130/92 mmHg indicates that diastolic control is the primary issue

Important Considerations

• Medication adherence: Ensure the patient is taking all medications as prescribed, as non-adherence is a common cause of resistant hypertension 2
• Potassium monitoring: The combination of spironolactone with lisinopril increases the risk of hyperkalemia
• Renal function: Monitor closely, especially with the addition of a fifth agent
• Lifestyle modifications: Reinforce the importance of sodium restriction, DASH diet, physical activity, and weight management 1

By adding spironolactone as a fifth agent while closely monitoring renal function and electrolytes, you can effectively address this case of resistant hypertension while maintaining patient safety.