Midodrine Dosing Schedule for Orthostatic Hypotension
The recommended dosing schedule for midodrine in treating orthostatic hypotension is 10 mg three times daily, administered at approximately 4-hour intervals during daytime hours only, with the last dose no later than 6 PM to avoid supine hypertension during sleep. 1
Dosing Regimen Details
- Standard dose: 10 mg three times daily 1
- Timing: Doses should be given during daytime hours when the patient needs to be upright 1
- Suggested schedule:
- First dose: Shortly before or upon arising in the morning
- Second dose: Midday
- Third dose: Late afternoon (not later than 6 PM) 1
- Interval: Approximately 4 hours between doses (can be shortened to 3-hour intervals if needed to control symptoms) 1
Dose Adjustments
- Starting dose: May begin with 2.5 mg three times daily and titrate upward based on response 1
- Maximum single dose: 20 mg (though this dose is associated with a high rate of supine hypertension in about 45% of patients) 1
- Maximum daily dose: 30 mg (higher doses have been tolerated but not systematically studied) 1
- Renal impairment: Start with 2.5 mg doses in patients with abnormal renal function 1
Important Administration Considerations
- Midodrine should not be given after the evening meal or less than 4 hours before bedtime to reduce the risk of supine hypertension during sleep 1
- The American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines support midodrine use for neurogenic orthostatic hypotension with a Class IIa recommendation (reasonable to administer) 2
- The medication should be taken at least 4 hours before bedtime to avoid supine hypertension 3
Monitoring and Safety
- Regular monitoring of supine and standing blood pressure is essential 1
- Treatment should be continued only in patients who demonstrate symptomatic improvement during initial treatment 1
- Discontinue midodrine if supine blood pressure increases excessively 1
- Clinical trials have demonstrated significant improvement in standing systolic blood pressure and symptoms of orthostatic hypotension with the three-times-daily dosing regimen 4, 5, 6
Special Populations
- No dose modifications are necessary based on age (≥65 vs. <65) or gender 1
- Pediatric dosing has not been adequately studied 1
Common Side Effects to Monitor
- Supine hypertension (occurs in up to 25% of patients) 3
- Piloerection (goosebumps)
- Scalp itching or tingling (reported in 13.5% of patients) 5
- Urinary urgency or retention (particularly in older males) 3
- Headache and nausea 5
The three-times-daily dosing schedule has been consistently shown to be effective in multiple clinical trials, with significant improvements in both standing blood pressure and symptoms of orthostatic hypotension 4, 5, 6.