Oral antiemetics for nausea and vomiting during pregnancy

Lowe, 2019

If 1 week of nondrug therapy for nausea and vomiting during pregnancy is ineffective, add pyridoxine and doxylamine; use:

pyridoxine 12.5 mg in the morning and at midday, and 25 mg at night, orally (uncategorised by the Therapeutic Goods Administration [TGA]) pyridoxine pyridoxine pyridoxine

PLUS

doxylamine 25 mg orally, at night. Increase as tolerated to 12.5 mg in the morning and at midday, and 25 mg at night (TGA category A)1. doxylamine doxylamine doxylamine

If the above therapy is ineffective and oral therapy is tolerated, add to the above regimen:

1metoclopramide 10 mg orally, 8-hourly if required (TGA category A)2 metoclopramide metoclopramide metoclopramide

OR

1ondansetron 4 to 8 mg orally, 8- to 12-hourly if required (TGA category B1)34Dormuth, 2021Lavecchia, 2018Zambelli-Weiner, 2019Huybrechts, 2018 ondansetron ondansetron ondansetron

OR

1prochlorperazine 5 to 10 mg orally, 6- to 8-hourly if required (maximum daily dose 30 mg)Lowe, 2019(TGA category C) prochlorperazine prochlorperazine prochlorperazine

OR

1promethazine 10 to 25 mg orally, 6- to 8-hourly if required (TGA category C). promethazine promethazine promethazine

If the above oral therapy is ineffective or not tolerated, use parenteral antiemetic therapy.

1 Doxylamine causes sedation; if daytime sedation is problematic, advise patients to use the night-time dose only.Return
2 For precautions related to the use of metoclopramide, see Common antiemetic drugs for management of nausea and vomiting in adults.Return
3 Ondansetron is available as an orally dispersible wafer preparation, which is useful for patients who are vomiting and cannot swallow the tablet preparation. The wafer should be placed on the tongue to dissolve.Return
4 Safety data in humans about ondansetron in pregnancy are conflicting; a small increase in cardiovascular malformations and orofacial clefts have been reportedDormuth, 2021.Return