Doxylamine (Unisom) Safety During Pregnancy
Doxylamine (Unisom) is considered safe to use during pregnancy and is recommended as a first-line pharmacologic therapy for nausea and vomiting of pregnancy (NVP) by the American College of Obstetricians and Gynecologists. 1
Safety Profile and Recommendations
- Doxylamine has extensive safety data and is one of the few medications that qualifies for FDA Pregnancy Category A status (when combined with pyridoxine as Diclegis/Diclectin) 2
- The combination of doxylamine and pyridoxine can be safely taken throughout the entire pregnancy with no increased risk of congenital malformations or adverse pregnancy outcomes 1
- For nausea and vomiting in pregnancy:
- First try non-pharmacological interventions (dietary modifications)
- If symptoms persist, consider ginger or vitamin B6 (pyridoxine) alone
- For moderate to severe symptoms, add doxylamine 1
Dosing and Administration
- For NVP: Typically used in combination with pyridoxine (vitamin B6)
- For sleep: Standard over-the-counter dosing (typically 25mg at bedtime)
- FDA labeling for Unisom (doxylamine) states: "If pregnant or breast-feeding, ask a health professional before use" 3
Evidence for Safety
A re-analysis of safety data for doxylamine use in pregnancy examined 22 original studies involving antihistamines, with 14,624 women exposed to doxylamine specifically. The analysis found no increased risk of congenital malformations associated with doxylamine use (summary odds ratio 1.07,95% CI: 0.93-1.23) 4.
Important Considerations
- Doxylamine is preferred over many other sleep aids or antiemetics during pregnancy due to its established safety record
- It is currently the only medication component (along with pyridoxine) in an FDA-approved medication specifically for NVP 5
- Using medications with established safety profiles like doxylamine is preferable to using medications with unproven maternal and fetal safety 5
Practical Recommendations
- For sleep issues in pregnancy: Doxylamine (Unisom) is a reasonable option when non-pharmacological approaches fail
- For nausea and vomiting: The combination of doxylamine and pyridoxine is recommended as first-line pharmacological therapy
- Duration: Can be used throughout pregnancy as needed, with no need to discontinue at any particular gestational age
Cautions
- As with any medication during pregnancy, use the lowest effective dose for the shortest duration needed
- Avoid alcohol when using doxylamine 3
- Consult a healthcare provider before use if you have asthma, glaucoma, or urinary problems 3
Doxylamine represents one of the better-studied medications for use during pregnancy, with a reassuring safety profile that makes it appropriate for use when clinically indicated.