Other sedation medications used alongside moderate sedation — promethazine and droperidol — side by side, as their own monographs state them. Both carry an FDA boxed warning; read it on the monograph before use.
| Agent | Route | Onset | Peak | Duration | Dose (as stated) | Reversal |
|---|---|---|---|---|---|---|
| Promethazine (Phenergan) | Deep IM preferred; if IV, dilute and give slowly through a running line | 2–5 minutes | Unknown | More than 120 minutes | 12.5–50 mg, one-time dose | None |
| Droperidol (Inapsine) | IM or slow IV | 3–10 minutes | 30 minutes | 120–240 minutes | 1.25–2.5 mg initial; additional 1.25 mg doses to the desired effect | None |
Every figure above is taken from the linked monograph on this site; a dash means the monograph does not state it. Verify all doses against the current package insert and your facility protocols before clinical use.
Promethazine (Phenergan)
Promethazine works as either an antiemetic or a low-dose sedative adjunct; the boxed warning is about IV route and line placement, not the dose itself — deep IM is preferred, and a diluted, slow IV push through a running line is the alternative.
Droperidol (Inapsine)
Droperidol is an antiemetic reached for after a first-line option has not worked, or when a patient’s history favors it; the boxed warning is about QT prolongation, so a baseline arrhythmia risk check comes before the dose, not after.
Educational reference for sedation providers, relocated from the previous version of this site — not a substitute for the current package insert, your facility protocols, or clinical judgment. Verify all doses against current references before clinical use.