What are the recommended antiemetics for pregnant women?

From the Guidelines

Pregnant women experiencing nausea and vomiting should be treated with vitamin B6 (pyridoxine) 10-25mg three times daily, combined with doxylamine 12.5mg, as the first-line treatment, as recommended by the American College of Obstetricians and Gynecologists (ACOG) and supported by the most recent evidence 1. The treatment of nausea and vomiting in pregnant women is crucial to prevent progression to hyperemesis gravidarum and ensure the well-being of both the mother and the fetus.

• The initial approach includes diet and lifestyle modifications, such as reducing spicy, fatty, acidic, and fried foods, and eating small, frequent, and bland meals, like the BRAT diet.
• If symptoms persist, ginger supplements (250mg four times daily) can be used as a non-pharmaceutical option.
• For more severe symptoms, prescription medications like metoclopramide 5-10mg three times daily, promethazine 12.5-25mg every 4-6 hours, or ondansetron 4-8mg every 8 hours may be considered, as stated in the expert consensus statements 1.
• However, the most recent and highest quality study 1 suggests that early treatment with vitamin B6 and doxylamine, followed by ondansetron, metoclopramide, promethazine, and intravenous glucocorticoids in moderate to severe cases, is the best practice approach.
• It is essential to discuss treatment options with a healthcare provider, considering the severity of symptoms, gestational age, and individual medical history, to determine the most appropriate treatment plan 1.

From the FDA Drug Label

Usage in Pregnancy: Safety for the use of prochlorperazine during pregnancy has not been established Therefore, prochlorperazine is not recommended for use in pregnant patients except in cases of severe nausea and vomiting that are so serious and intractable that, in the judgment of the physician, drug intervention is required and potential benefits outweigh possible hazards Promethazine hydrochloride tablets should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus Published epidemiological studies on the association between ondansetron use and major birth defects have reported inconsistent findings and have important methodological limitations that preclude conclusions about the safety of ondansetron use in pregnancy

The recommended antiemetics for pregnant women are not explicitly stated in the provided drug labels. However, based on the available information:

• Ondansetron may be used during pregnancy, but the safety data is limited and inconsistent, and the drug label does not provide a clear recommendation for its use in pregnant women 2.
• Prochlorperazine is not recommended for use in pregnant patients except in cases of severe nausea and vomiting where the potential benefits outweigh the possible hazards 3.
• Promethazine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus 4. It is essential to consult a healthcare professional to determine the best course of treatment for nausea and vomiting during pregnancy, as the risk-benefit ratio of each medication should be carefully evaluated.

From the Research

Recommended Antiemetics for Pregnant Women

The following antiemetics are recommended for pregnant women:

• Pyridoxine and metoclopramide (category A) as first-line treatment for hyperemesis gravidarum 5
• Doxylamine succinate/pyridoxine hydrochloride, given a pregnancy safety rating of A, is recommended as first-line pharmacologic treatment for NVP 6
• Antihistamines, metoclopramide, ondansetron, and phenothiazines are also options for pharmacologic management 6
• Ondansetron is associated with improvement for a range of symptom severity, and its use as a second-line antiemetic should not be discouraged if first-line antiemetics are ineffective 7
• Metoclopramide is safe and effective, and can be used alone or in combination with other antiemetics, but should be used as second-line therapy due to the risk of extrapyramidal effects 7

Key Considerations

• Assessment of severity is important, and tools such as the Pregnancy-Unique Quantification of Emesis (PUQE) and HyperEmesis Level Prediction (HELP) can be used to classify the severity of NVP and HG 7
• Ketonuria is not an indicator of dehydration and should not be used to assess severity 7
• Women should be asked about previous adverse reactions to antiemetic therapies, and prompt cessation of medications should occur if adverse reactions occur 7
• Combinations of different drugs can be used in women who do not respond to a single antiemetic 7