What medications are used to treat hypotension?

Medications for Low Blood Pressure (Hypotension)

Midodrine is the first-line medication for treating symptomatic orthostatic hypotension, with fludrocortisone as an alternative or add-on therapy when a single agent is insufficient. 1, 2

Types of Hypotension

Hypotension can be classified as:

• Orthostatic hypotension: Drop in systolic BP ≥20 mmHg or diastolic BP ≥10 mmHg within 3 minutes of standing 3
• Delayed orthostatic hypotension: BP drop occurring after 3 minutes of standing 3
• Symptomatic hypotension: Presenting with dizziness, lightheadedness, weakness, or syncope

Treatment Algorithm

Step 1: Non-Pharmacological Interventions

Before initiating medications, these measures should be implemented:

• Increased salt and fluid intake 3, 4
• Moderate physical activity to prevent deconditioning 5, 3
• Compression garments for legs and abdomen 5, 3
• Avoiding prolonged standing 3
• Elevating the head of the bed during sleep 3
• Gradual position changes 3
• Avoiding medications that worsen hypotension 3

Step 2: Pharmacological Treatment

First-Line Medications:

1. Midodrine (ProAmatine)

   • Mechanism: Alpha-1 agonist that increases vascular tone 1
   • Dosing: Starting at 2.5-5 mg three times daily (last dose no later than 6 PM) 1
   • Efficacy: Increases standing systolic BP by 15-30 mmHg within 1 hour 1
   • Key consideration: FDA-approved specifically for orthostatic hypotension 1

2. Fludrocortisone (Florinef)

   • Mechanism: Mineralocorticoid that promotes sodium retention and increases blood volume 2
   • Dosing: Usually 0.1-0.3 mg daily
   • Key consideration: Effective for volume expansion but monitor for supine hypertension 2

Second-Line Medications:

1. Droxidopa (Northera)

   • Mechanism: Synthetic precursor of norepinephrine
   • Key consideration: FDA-approved for neurogenic orthostatic hypotension 5

2. Short-acting antihypertensives for nighttime use (when supine hypertension is present):

   • Clonidine or guanfacine (affect baroreceptor activity) 5
   • Short-acting calcium blockers (e.g., isradipine) 5
   • Short-acting beta-blockers (e.g., atenolol, metoprolol tartrate) 5
   • Enalapril (if unable to tolerate preferred agents) 5

Special Considerations

Monitoring and Precautions

• Supine hypertension: Monitor for BP >200 mmHg when lying down, especially with midodrine 1
• Timing of medication: Take last dose of midodrine 3-4 hours before bedtime to avoid nighttime supine hypertension 1
• Renal function: Assess renal function before initiating midodrine; use with caution in renal impairment 1
• Drug interactions: Use caution when combining with other vasoconstrictors, cardiac glycosides, or medications that affect heart rate 1

Treatment Goals

• Focus on symptom improvement rather than normalizing blood pressure 3
• Aim to reduce falls, syncope, and improve standing time and daily activities 4
• Balance treatment of orthostatic hypotension with management of supine hypertension 3, 1

Medication Selection Based on Clinical Scenario

• Severe symptomatic orthostatic hypotension: Midodrine as first-line, may add fludrocortisone if inadequate response 2
• Orthostatic hypotension with volume depletion: Fludrocortisone may be preferred initially
• Orthostatic hypotension with supine hypertension: Careful dosing of midodrine with timing restrictions, consider shorter-acting agents 1
• Diabetic autonomic neuropathy: Same medications apply, but with careful monitoring 5

Common Pitfalls

• Treating asymptomatic hypotension: Medication therapy should be reserved for symptomatic patients whose lives are considerably impaired 1
• Ignoring supine hypertension: This common side effect requires careful monitoring and medication timing 1
• Inadequate non-pharmacological measures: Always implement these before or alongside medication therapy 3, 4
• Inappropriate fluid restriction: Adequate fluid intake is essential for management 3, 4
• Overlooking medication causes: Review and modify medications that may cause or worsen hypotension 3, 4

By following this structured approach to treating hypotension, focusing first on non-pharmacological interventions and then adding appropriate medications based on symptom severity and individual patient factors, most cases of symptomatic hypotension can be effectively managed.