Low-Dose Promethazine for Antiemesis without Sedation

Promethazine

Parenteral promethazine (Phenergan, Wyeth) is effective as an antiemetic agent, but it tends to exert significant sedative effects at the standard dosage of 25 mg, especially when it is used along with narcotic analgesics. Researchers at Anne Arundel Medical Center in Annapolis, Maryland, say that even a dose as low as 6.25 mg can still be effective.

At one hour, 33 of 46 patients taking low-dose promethazine had no nausea or vomiting, compared with 24 of 41 patients taking generic ondansetron (Zofran canadian, Glaxo-SmithKline) (4 mg). Only three patients in each group showed sedative effects.