What medications are used to treat hypotension (low blood pressure)?

Medications for Low Blood Pressure

For symptomatic orthostatic hypotension, midodrine (2.5-5 mg three times daily) is the first-line pharmacological treatment, with fludrocortisone (0.05-0.1 mg daily) as an alternative or add-on therapy when non-pharmacological measures fail. 1, 2, 3

Context-Specific Treatment Approaches

Orthostatic Hypotension (Most Common Scenario)

First-line pharmacological agents:

• Midodrine is FDA-approved and recommended as first-line therapy 4, 1, 3

  • Dosing: Start 2.5-5 mg three times daily, can increase to 10 mg three times daily 1, 2
  • Mechanism: Peripheral α1-adrenergic agonist causing arteriolar and venous constriction 1, 2
  • Critical timing: Last dose must be at least 3-4 hours before bedtime (avoid after 6 PM) to prevent supine hypertension 1, 2
  • Increases standing systolic BP by 15-30 mmHg for 2-3 hours 1

• Fludrocortisone is recommended as alternative first-line or combination therapy 1, 2

  • Dosing: Start 0.05-0.1 mg daily, titrate to 0.1-0.3 mg daily (maximum 1.0 mg daily) 1, 2
  • Mechanism: Mineralocorticoid that increases sodium retention and plasma volume expansion 1, 2
  • Contraindications: Active heart failure, severe renal disease, pre-existing supine hypertension 1
  • Monitoring required: Check potassium levels periodically (can cause hypokalemia), monitor for supine hypertension and peripheral edema 1

Second-line agents:

• Droxidopa is FDA-approved for neurogenic orthostatic hypotension, particularly effective in Parkinson's disease, pure autonomic failure, and multiple system atrophy 1, 2

• Pyridostigmine may be beneficial for refractory cases with a favorable side effect profile, though evidence is limited 1

Combination therapy with midodrine plus fludrocortisone should be considered for non-responders to monotherapy 1

Acute Hypotension in Perioperative/Critical Care Settings

For vasopressor support:

• Norepinephrine is the first-choice vasopressor, targeting mean arterial pressure (MAP) of 65 mmHg 4

• Vasopressin (0.03 units/minute) can be added to norepinephrine to raise MAP or decrease norepinephrine dosage 4

• Epinephrine can be added when additional agent is needed to maintain adequate blood pressure 4

• Dopamine is only recommended in highly selected patients with low risk of tachyarrhythmias and absolute or relative bradycardia 4

• Phenylephrine should be used when hypotension is accompanied by tachycardia due to reflex bradycardia risk 4

For fluid-responsive hypotension:

• Perform passive leg raise (PLR) test first—if cardiac output increases, give crystalloid bolus (minimum 30 mL/kg) 4
• If PLR test negative, focus on vasopressor or inotropic support rather than fluids 4

Vasovagal Syncope with Hypotension

Pharmacological options (when non-pharmacological measures fail):

• Midodrine is reasonable for recurrent vasovagal syncope with no history of hypertension, heart failure, or urinary retention 4

• Fludrocortisone might be reasonable for recurrent vasovagal syncope with inadequate response to salt and fluid intake 4

• Beta-blockers might be reasonable in patients ≥42 years old with recurrent vasovagal syncope, though European guidelines do not recommend them 4

Heart Failure with Reduced Ejection Fraction and Low Blood Pressure

This scenario requires a different approach—do NOT discontinue guideline-directed medical therapy (GDMT) for asymptomatic low BP: 4

• SGLT2 inhibitors and mineralocorticoid receptor antagonists (MRAs) have minimal BP-lowering effect and should be prioritized 4

• If systolic BP <80 mmHg or symptomatic hypotension with major symptoms, refer to heart failure specialist 4

• For stable patients on GDMT with low BP, evaluate for other causes (valvular disease, ischemia, non-cardiac medications like alpha-blockers) rather than reducing heart failure medications 4

Essential Non-Pharmacological Measures (Must Implement First)

Before starting medications, these interventions are mandatory: 1, 2

• Fluid intake: 2-3 liters daily 1, 2
• Salt intake: 6-9 grams daily (unless contraindicated by heart failure) 1, 2
• Acute water bolus: ≥480 mL provides temporary relief with peak effect at 30 minutes 1
• Physical counter-maneuvers: Leg crossing, squatting, stooping, muscle tensing during symptom onset 1, 2
• Compression garments: Thigh-high stockings and abdominal binders 1, 2
• Head-up bed position: Elevate head of bed 10° during sleep to prevent nocturnal polyuria and supine hypertension 1, 2
• Smaller, frequent meals: Reduces post-prandial hypotension 1, 2
• Medication review: Discontinue or modify culprit medications (diuretics, vasodilators, alpha-blockers, antidepressants) 1, 2

Critical Monitoring and Safety Considerations

Treatment goal: Minimize postural symptoms, NOT restore normotension 1, 2

Supine hypertension monitoring is essential with all pressor agents—this is the most important limiting factor and can cause end-organ damage 1

BP measurement technique: Measure after 5 minutes lying/sitting, then at 1 and 3 minutes after standing 1

Reassessment timing: Follow up within 1-2 weeks after medication changes 1

Balance risk: Weigh fall/injury risk from hypotension against cardiovascular protection from antihypertensive medications 1