In a patient with hypotension, which medication is best to discontinue first, a diuretic (such as furosemide) or another antihypertensive medication?

Discontinuing Diuretics First in Hypotension

In a patient with hypotension (BP 100/60), the diuretic (such as furosemide) should be discontinued first rather than other antihypertensive medications. 1

Rationale for Discontinuing Diuretics First

Diuretics work by increasing urine output and reducing blood volume, which directly impacts blood pressure. When a patient presents with hypotension, continuing diuretic therapy can worsen the situation by:

1. Further reducing intravascular volume
2. Exacerbating hypotension
3. Potentially causing circulatory collapse

Physiological Effects of Diuretics in Hypotension

• Furosemide and other loop diuretics can cause excessive diuresis leading to dehydration and blood volume reduction 2
• This volume reduction can precipitate circulatory collapse and possibly vascular thrombosis and embolism, particularly in elderly patients 2
• Diuretics may decrease arterial responsiveness to norepinephrine, further complicating management of hypotension 2

Decision Algorithm for Medication Discontinuation in Hypotension

1. First to discontinue: Diuretics (especially loop diuretics like furosemide)

   • Immediate effect on volume status
   • Directly addresses the hypotensive state
   • Prevents further volume depletion

2. Second to consider discontinuing (if hypotension persists):

   • Vasodilators (CCBs, ACE inhibitors, ARBs)
   • Beta-blockers (with caution - avoid abrupt cessation) 1

3. Last to discontinue:

   • Medications treating compelling indications (e.g., beta-blockers for heart failure with reduced ejection fraction)

Special Considerations

Monitoring After Discontinuation

• Closely monitor blood pressure, heart rate, and symptoms of fluid overload
• Check electrolytes, BUN, and creatinine to assess renal function
• Watch for rebound hypertension, especially if blood pressure normalizes quickly

Medication-Specific Considerations

• Loop diuretics (furosemide): Can cause orthostatic hypotension, especially in elderly patients 3
• Beta-blockers: Avoid abrupt cessation due to risk of rebound hypertension or tachycardia 1
• ACE inhibitors/ARBs: Consider maintaining if treating heart failure or diabetic nephropathy, unless severe hypotension persists 1

Common Pitfalls to Avoid

• Discontinuing multiple medications simultaneously: This can make it difficult to identify which medication was causing the hypotension
• Failing to monitor for orthostatic hypotension: Always check for postural drops in blood pressure
• Not considering drug interactions: Some combinations (e.g., diuretics with ACE inhibitors) can potentiate hypotension 2
• Overlooking non-medication causes: Dehydration, infection, or other medical conditions can cause or contribute to hypotension

Evidence-Based Approach

The ACC/AHA guidelines indicate that diuretics should be discontinued in cases of severe hypotension 1. The FDA labeling for furosemide specifically warns that "excessive diuresis may cause dehydration and blood volume reduction with circulatory collapse" 2, making diuretics the logical first choice for discontinuation when managing hypotension.