What additional antihypertensive medications can be added for a patient with persistent hypertension (200/100mmHg) despite being on GTN (glyceryl trinitrate) infusion, Arkamine (clonidine) 200mcg, cilnidipine 20mg, and moxonidine 0.3mg?

Management of Resistant Hypertension (200/100 mmHg)

For a patient with persistent severe hypertension (200/100 mmHg) despite multiple medications, adding a thiazide/thiazide-like diuretic and/or spironolactone is strongly recommended as the next step in management. 1, 2

Current Medication Analysis

The patient is currently on:

• GTN (glyceryl trinitrate) infusion 8ml/hr
• Arkamine (clonidine) 200mcg
• Cilnidipine 20mg (calcium channel blocker)
• Moxonidine 0.3mg (centrally acting agent)

This regimen includes a nitrate, a centrally acting agent (clonidine), another centrally acting agent (moxonidine), and a calcium channel blocker, but lacks:

• A diuretic
• An ACE inhibitor or ARB
• A beta-blocker

Recommended Additions (in order of priority)

1. Add a thiazide/thiazide-like diuretic

   • Chlorthalidone or indapamide are preferred due to their proven efficacy in reducing cardiovascular events 1
   • These are particularly effective for resistant hypertension when added to existing regimens

2. Add spironolactone

   • Spironolactone is specifically indicated as add-on therapy for treatment of hypertension in patients not adequately controlled on other agents 2
   • Particularly effective for resistant hypertension
   • Starting dose: 25mg daily

3. Consider intravenous nicardipine

   • If rapid blood pressure control is needed, nicardipine is a dihydropyridine calcium channel blocker that can be administered intravenously 3, 4
   • Dosing: 5-15 mg/h as continuous IV infusion, starting at 5 mg/h and increasing every 15-30 min by 2.5 mg until goal BP 3

4. Add an ACE inhibitor or ARB

   • These are recommended as first-line therapy for non-Black patients 1
   • Consider enalaprilat IV (0.625-1.25 mg) if rapid control is needed 3
   • For oral therapy, start with a standard dose of an ACE inhibitor or ARB

Additional Considerations

For Immediate Control (if needed)

• Urapidil (12.5-25 mg IV bolus, 5-40 mg/h as continuous infusion) may be effective, especially if the patient has myocardial ischemia 3
• Labetalol (0.25-0.5 mg/kg IV bolus; 2-4 mg/min continuous infusion) if there are no contraindications such as heart failure, asthma, or bradycardia 3

Monitoring

• Monitor renal function and electrolytes within 2-4 weeks of initiating new therapy, especially with diuretics, ACE inhibitors, or ARBs 1
• Check blood pressure within 48-72 hours after medication adjustment 1
• Target blood pressure should be <160/105 mmHg acutely and <130/80 mmHg long-term 1

Important Cautions

• Avoid sodium nitroprusside if possible due to risk of cyanide toxicity 5, 6
• Be cautious with beta-blockers if the patient has heart failure, asthma, or bradycardia 3
• When using multiple antihypertensive agents, be vigilant for orthostatic hypotension
• If using spironolactone, monitor potassium levels closely, especially if combined with ACE inhibitors or ARBs

The triple combination of an ARB, thiazide diuretic, and calcium channel blocker is particularly effective and well-tolerated for resistant hypertension 1. Since the patient is already on a calcium channel blocker (cilnidipine), adding a thiazide diuretic and an ARB would complete this effective triple therapy.