Doxylamine succinate – pyridoxine hydrochloride (Diclectin®)

Section 1.1

Midwives may independently prescribe, order and administer this drug.

Doxylamine succinate competes with histamine for H1-receptor sites which block chemoreceptor trigger zones which control the symptoms of nausea and vomiting. The pyridoxine hydrochloride component is a vitamin which has antiemetic effects.

Indications and Clinical Use:

Used orally for the control of nausea and vomiting in pregnancy.

The drug of choice remains Diclectin, the delayed-release combination of doxylamine and vitamin B6. Nausea and vomiting of pregnancy (NVP) is a common medical condition of pregnancy, affecting up to 80% of all pregnancies.


Hypersensitivity to doxylamine, pyridoxine, or any component of the formulation.

Warnings and Precautions:

May cause CNS depression, which may impair physical or mental abilities.
Use with caution in patients with hypertensive disorders and thyroid dysfunction.




Category L3 – No Human Data – Probably Compatible

Doxylamine may be excreted in breast milk, and can result in sedative effects in nursing infants. Approved use of doxylamine and pyridoxine is limited to the prenatal period.

Adverse Reactions:

Palpitation, tachycardia, dizziness, drowsiness, headache, constipation, diarrhea, dry mucous membranes and epigastric pain.

Dosage and Administration:

Give 10 mg of doxylamine combined with 10 mg of pyridoxine (Diclectin, delayed release) up to 4 tablets daily (ie, 2 at bedtime, 1 in the morning, and 1 in the afternoon). Adjust schedule and dose according to severity of symptoms.


10-12 hours