Arteriolar vasodilator
Hydralazine
Hypotensive — violet/white stripes 20 mg/mL
Slow-onset arterial vasodilator; expect reflex tachycardia.
Typical adult doses
| Indication | Dose | Onset | Duration |
|---|---|---|---|
| Hypertension | 5–10 mg IV | 10–20 min | 2–4 h |
Mechanism
Direct arteriolar smooth-muscle relaxation.
Key effects
- ↓ SVR, reflex ↑HR
Watch out for
- Delayed onset — don’t stack doses
- Reflex tachycardia
Pimp questions
Pimp question
Why not stack hydralazine doses quickly?
Answer
Onset is 10–20 min; stacking causes delayed hypotension.