Which medication should be discontinued in a patient taking Norvasc (amlodipine) 10 mg, hydrochlorothiazide 12.5 mg, and losartan 50 mg daily who has hypotension (BP 88/47 mm Hg)?

Discontinue Hydrochlorothiazide First

In a patient with symptomatic hypotension (BP 88/47 mmHg) on triple antihypertensive therapy, hydrochlorothiazide 12.5 mg should be discontinued first. This is the lowest-dose, least potent agent in the regimen and its removal will have the most immediate impact on volume status while maintaining cardiovascular protection from the other agents.

Rationale for Discontinuing Hydrochlorothiazide

Thiazide diuretics contribute to hypotension through volume depletion, which is particularly problematic when combined with vasodilators (amlodipine) and RAAS blockers (losartan). The 12.5 mg dose is already at the lower end of the therapeutic range 1, 2, making dose reduction impractical.

Why Not the Other Medications?

Amlodipine 10 mg (Norvasc) provides:

• Long half-life ensuring sustained BP control 3
• Proven cardiovascular protection in high-risk patients 4
• The maximum dose suggests this patient may have required aggressive BP control previously
• Should be maintained for its cardioprotective effects, though dose reduction to 5 mg could be considered if BP remains low after stopping HCTZ

Losartan 50 mg provides:

• Renal protection, especially important if diabetes or proteinuria present 5
• Cardiovascular risk reduction
• Better tolerability profile than other antihypertensive classes 6
• The dose is mid-range (50-100 mg daily) 1, 2, allowing for dose reduction if needed
• Should be maintained for organ protection

Clinical Approach

Immediate Management:

1. Stop hydrochlorothiazide immediately - no tapering required for this dose
2. Monitor BP closely over next 48-72 hours
3. Assess for orthostatic symptoms and volume status
4. Check serum potassium (may rise after stopping HCTZ) 7

If BP Remains Low After Stopping HCTZ:

• Reduce amlodipine from 10 mg to 5 mg - the long half-life means effects persist even with missed doses 3
• Maintain losartan for organ protection unless BP remains critically low
• Consider underlying causes: dehydration, infection, cardiac dysfunction

Target BP After Adjustment:

• Aim for BP >100/60 mmHg to avoid symptomatic hypotension
• Once stable, reassess need for triple therapy versus dual therapy
• Most patients with controlled hypertension can be maintained on dual therapy (ARB + CCB or ARB + diuretic) 1, 2

Important Caveats

Do not abruptly discontinue all medications - this risks rebound hypertension and loss of cardiovascular protection. The sequential approach (stop HCTZ first, then reduce amlodipine if needed) minimizes risk while addressing hypotension 8.

Assess for secondary causes of the low BP:

• Recent illness, dehydration, or diarrhea
• New medications (especially NSAIDs, which can paradoxically worsen BP control)
• Cardiac events (acute MI, heart failure decompensation)
• Sepsis or other acute illness

The combination of losartan + amlodipine without a diuretic is well-tolerated and effective 9, and may be the optimal long-term regimen for this patient once BP stabilizes.