Taking medications during pregnancy can be very upsetting for women as the general belief is that they will hurt their baby(ies). However, the risks of chronic dehydration, malnutrition, metabolic and emotional stress, as well as reduced mobility must be considered. These have been demonstrated to increase the risk of complications in mothers and possibly even in their child(ren). Conversely, most studies of medications commonly used for HG have not been found to significantly increase the risk of malformations in the baby.

It is important to not only decide on the correct medication, or combination as is most common, but also to make sure a medication is being tolerated and taken correctly for optimal effectiveness. If a mother cannot swallow a pill or vomits it back up before it dissolves, then oral medications need to be replaced with medications that can be given a different route, such as a rapid dissolving films, patches or subcutaneous infusions, or even a cream or suppository made by a compounding pharmacy. Trying the most effective medications in different forms is important before trying different medications or deciding any or all meds do not work.

Medication Strategies

Keep in mind, the primary goal is to reduce nausea and vomiting so the mother can increase her intake and stay as mobile as possible. Risks and benefits must be considered in every case as each mother is unique.
- Kimber MacGibbon, RN

Changing medications abruptly or frequently is counterproductive; avoid changing them early in pregnancy if improvement is noted.

Effectiveness changes with increased doses or frequency, changes in route or medication combinations.

Scheduled dosing improves response so discuss taking on a strict schedule with your doctor.

Metabolic imbalance impairs response to meds so make sure you have adequate electrolytes and fluids.

Side-effects are better prevented than managed, especially constipation.

If you have a history of HG, plan and treat proactively, don't wait until you are very sick.

Wean all meds slowly after a few weeks after symptoms resolve and you can eat and drink adequately.

Medication may be needed until delivery and is better than frequents ups and downs.

Women can offer valuable insight into their care and should discuss ideas with their doctor.

HG is traumatic so it should be treated compassionately and women should contact the HER Foundation for support.


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  • Ondansetron in Pregnancy and Risk of Adverse Fetal Outcomes. N Engl J Med 2013; 368:814-823.
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  • Posttraumatic stress symptoms following pregnancy complicated by hyperemesis gravidarum. J Matern Fetal Neo Med. 2011 Nov;24(11):1307-11.
  • Symptoms and pregnancy outcomes associated with extreme weight loss among women with HG. J Women’s Health. 2009 Dec;18(12):1981-7.www.HelpHER.org/HER-Research