Uses

Indicated for the treatment of nausea and vomiting of pregnancy (morning sickness) in women who do not respond to conservative management. It is the only FDA-approved pharmacological treatment specifically for this condition.

Do not use if

Contraindicated in patients with known hypersensitivity to doxylamine, other ethanolamine antihistamines, or pyridoxine. Should not be used concurrently with monoamine oxidase inhibitors (MAOIs).

Side effects

The most common side effect is somnolence or drowsiness. Other effects may include dizziness, dry mouth, and headache. Patients should avoid activities requiring alertness until the drug's effects are known.

Warnings

May cause CNS depression; caution when combined with alcohol or other CNS depressants. Use with caution in patients with asthma, increased intraocular pressure, urinary retention, or pyloric obstruction. Safety in the first trimester should be discussed with a healthcare provider.

How it works

Doxylamine is a first-generation antihistamine with anticholinergic properties that acts as an antiemetic. Pyridoxine (vitamin B6) is a water-soluble vitamin involved in amino acid metabolism; its mechanism in reducing nausea is not fully established but it is thought to act synergistically with doxylamine.

Storage

Store at controlled room temperature, 20°C to 25°C (68°F to 77°F). Keep out of reach of children.