Mixed α/β agonist
Ephedrine
Vasopressor — violet 5 mg/mL (diluted or prefilled)
For low BP with a slow heart rate; stops working with repeated doses.
Typical adult doses
| Indication | Dose | Onset | Duration |
|---|---|---|---|
| Bolus | 5–10 mg IV, repeat (label total 50 mg) | ≈1 min | ≈10–15 min |
Mechanism
Indirect (releases norepinephrine) plus direct α and β agonism.
Key effects
- ↑ HR, ↑ BP, ↑ contractility
Watch out for
- Tachyphylaxis — depletes norepinephrine stores
- Tachycardia
Pimp questions
Pimp question
Why does ephedrine stop working after several doses?
Answer
Tachyphylaxis: it releases presynaptic norepinephrine stores, which become depleted.