Hydralazine
IV 5 mg slowly, repeated every 20 minutes (max 20 mg) for severe hypertension in pregnancy, with a small fluid bolus first.
On this page
Dose
| Route | Dose |
|---|---|
| IV bolus | 5 mg slowly, repeat every 20 minutes to max 20 mg |
| IV infusion | 50–150 micrograms/minute (HDU) |
| Oral | 25 mg 3–4 times daily |
Cautions
- Give 250–500 mL crystalloid before or with the first dose in pregnancy to avoid a sudden BP drop.
- Fast heart rate, headache, flushing.
Frequently asked questions
Why is a fluid bolus given with hydralazine?
To prevent a sudden fall in BP and placental perfusion.
Used in these guides
Sources
Doses on this page are typical doses from the sources above. Always confirm with a current drug reference, the product leaflet and your hospital protocol, especially in children, pregnancy and kidney or liver disease.
For FCPS Part 1
Revising for FCPS Part 1? Hydralazine is covered in our textbook chapter Antihypertensives in pregnancy, with practice MCQs.