What is Doxylamine/pyridoxine used for?

Doxylamine/pyridoxine is evaluated for the following indications with varying evidence strength: Nausea and vomiting of pregnancy (evidence tier A), Hyperemesis gravidarum (evidence tier B), Insomnia and sleep disorders (evidence tier F). See the full indication matrix with dosing and citations above on this page.

What are the side effects of Doxylamine/pyridoxine?

Common side effects of Doxylamine/pyridoxine (≥ 1 in 100): Drowsiness (most common), Dry mouth, Constipation, Dizziness, Fatigue. See the Safety section for uncommon and serious reactions.

Is Doxylamine/pyridoxine safe during pregnancy?

FDA category A. FDA category A. Specifically developed for pregnancy use. Safety confirmed in a 200,000-pregnancy cohort. Used throughout all trimesters when indicated.

Is Doxylamine/pyridoxine compatible with breastfeeding?

Doxylamine passes into milk in small amounts and may cause infant drowsiness. Use cautiously during lactation or avoid.

Who should not take Doxylamine/pyridoxine?

Doxylamine/pyridoxine is contraindicated in: Hypersensitivity to doxylamine, pyridoxine, or other alkylamines; Angle-closure glaucoma; Urinary retention with BPH; Epilepsy with active seizures; Concurrent MAO inhibitors. Full list in the Safety section.

Doxylamine/pyridoxine

Combination of H1-antihistamine and vitamin B6

ATC code: R06AA09 (Doxylamine)

Mechanism of action

Doxylamine is a first-generation H1-antihistamine with antimuscarinic action; blocks the medullary vomiting center. Pyridoxine (vitamin B6) is a cofactor in serotonin, GABA, and dopamine synthesis; exact antiemetic mechanism is unclear, but efficacy is supported by clinical trials. The doxylamine 10 mg + pyridoxine 10 mg combination is first-line for nausea and vomiting of pregnancy per 2018. In Spain sold under the Cariban brand since the 1960s.

Indications

Nausea and vomiting of pregnancy

First line

First-line for mild-to-moderate nausea and vomiting of pregnancy per 2018 and the Spanish SEGO 2022. Starting dose 1 capsule at bedtime; with persistent symptoms, increase to 1 capsule in the morning and 2 at bedtime (up to 40 mg doxylamine and 40 mg pyridoxine daily). Non-pharmacological measures are recommended before drug therapy: small frequent meals, ginger, P6 acupressure. Safety confirmed in a 200,000-pregnancy cohort without described teratogenicity.

Doxylamine/pyridoxine

Mechanism of action

Indications

Nausea and vomiting of pregnancy

Hyperemesis gravidarum

Marketing claims without evidence base

Insomnia and sleep disorders

Practical notes

Timing and administration

Check interaction with another drug

Safety

Contraindications

Serious adverse effects

Common adverse effects

PregnancyFDA A

Breastfeeding

Frequently asked