dox-il-a-meen peer-ih-dox-een

Trade Name(s)

  • Bonjesta
  • Diclegis
  • Diclectin Canadian Tradename

Ther. Class.

Pharm. Class.
vitamin B6 analogues


Treatment of nausea and vomiting during pregnancy that has not responded to conservative management.


Combination of an antihistamine and a vitamin B6  analog. Mechanism not known.

Therapeutic Effect(s):

Decreased nausea and vomiting associated with pregnancy.


Absorption: Well absorbed following oral administration. Food delays/↓ absorption.

Distribution: Doxylamine probably enters breast milk

Metabolism and Excretion: Doxylamine is mostly metabolized by the liver, inactive metabolites are renally excreted. Pyridoxine is a pro-drug, converted to its active metabolite by the liver.

Half-life:  Doxylamine– 12.5 hr;  pyridoxine– 0.4–0.5 hr

TIME/ACTION PROFILE (anti-emetic effect)

POunknownunknown8–24 hr


Contraindicated in:

  • Hypersensitivity to doxylamine or pyridoxine
  • Concurrent use of MAOIs
  • Lactation: Doxylamine probably enters breast milk and may cause irritability, excitement, or sedation in infants; breast feeding should be avoided.

Use Cautiously in:

  • Asthma
  • ↑ intraocular pressure or narrow angle glaucoma
  • Stenosing peptic ulcer or pyloroduodenal obstruction
  • Urinary bladder-neck obstruction
  • Pedi:  Safety and effectiveness not established

Adverse Reactions/Side Effects

CNS: drowsiness

* CAPITALS indicate life-threatening.
Underline indicate most frequent.



  • ↑ risk of CNS depression with other  CNS depressants  including alcohol, other antihistamines, opioid analgesics, and  sedative/hypnotics.
  • Concurrent use of  MAOIs  ↑ intensity/duration of adverse CNS (anticholinergic) reactions


Delayed-Release Tablets

PO (Adults):  Day 1– 2 tablets (doxylamine 10 mg/pyridoxine 10 mg) at bedtime; if symptoms are controlled continue this regimen;  Day 2, if symptoms persist into afternoon on day 2– 2 tablets at bedtime on day 2 and then 1 tablet in the morning on day 3 and 2 tablets in the evening; if symptoms are controlled, continue this regimen;  Day 4, if symptoms persist– 1 tablet in the morning, 1 tablet mid-afternoon and 2 tablets at bedtime (not to exceed four tablets daily).

Extended-Release Tablets

PO (Adults):  Day 1– 1 tablet (doxylamine 20 mg/pyridoxine 20 mg) at bedtime; if symptoms are controlled, continue this regimen;  Day 2, if symptoms persist on day 2– 1 tablet in AM and 1 tablet at bedtime on day 2; if symptoms are controlled, continue this regimen (not to exceed two tablets daily).

Availability (generic available)

Delayed-release tablets (Diclegis): doxylamine 10 mg/pyridoxine 10 mg

Extended-release tablets (Bonjesta): doxylamine 20 mg/pyridoxine 20 mg


  • Assess for frequency and amount of emesis daily during therapy. Reassess need for medication as pregnancy progresses.
  • Monitor hydration status to prevent dehydration.

Lab Test Considerations:

May cause false positive urine screening tests for methadone, opiates, and PCP.

Potential Diagnoses


  • PO Administer on an empty stomach with a full glass of water; food delays onset of medication. Swallow tablets whole; do not crush, break, or chew.

Patient/Family Teaching

  • Instruct patient to take as directed. Do not take more than prescribed amount.
  • May cause drowsiness. Caution patient to avoid driving and other activities requiring alertness until response to medication is known.
  • Advise patient to avoid alcohol and CNS depressants, including sedatives, tranquilizers, antihistamines, opioids, and some cough and cold medications with doxylamine pyridoxine.
  • Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications.
  • Advise female patient to avoid breast feeding during therapy.

Evaluation/Desired Outcomes

Decrease in frequency of nausea and vomiting during pregnancy.

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