Are medications working?

What are your expectations of medications? Here are some frequent concerns we hear and what we know about effective medication management. Many women expect relief of nausea and vomiting immediately from medications, but medications don't target nausea. Additionally, other symptoms like acid reflux and gastroparesis may not be improved by common antiemetic medications.

Nausea’s pathway is still being understood and there are multiple causes in HG, thus no medications make all of the nausea go away. Medications like Kytril (granisetron) and Zofran (ondansetron) are commonly used for HG because they are usually very effective at reducing vomiting if taken on a strict schedule in a high enough dose. They affect the serotonin receptors in the GI system and prevent triggering of the vomiting center in the brain. They are not formulated to target nausea symptoms but may give some relief. Additional medications may be added for nausea such as promethazine, metoclopramide, acid reducing medication like famotidine, antihistamine, and vitamin B1 (different than B6).

  • Share our treatment algorithm with your OB/midwife and see if they will consider additional options.

Did you know that more than one prescription medication is typically required to adequately manage HG and minimize weight loss? Combining medications is common. Don’t expect all nausea and vomiting to end by taking one medication. Your symptoms may also increase throughout the first trimester and vary for months longer. An increase in symptoms doesn’t mean your medication stopped working. You may just be having a bad day, were more active than your body could tolerate, or need additional medication or fluids and vitamins.

  • Remember these tips: Stopping medication quickly can make you sicker, so ask about weaning slowly. Also, try to start one medication at a time, so you can see which one is helping your symptoms.
  • Share our Treatment Algorithm with your OB/midwife and see if they will consider additional options.

Without adequate hydration, electrolytes, and key vitamins (thiamin/B1, B6, K, Mg, Na), medications may not work as effectively. Vitamin deficiencies worsen nausea and vomiting. See our Patient Treatment Guide for options to discuss with your OB. Many with HG need multiple medications and many health professionals have not received much training on this.

  • Share our Treatment Algorithm with your OB to see what additional options they will offer you.
  • Read more on figuring out if you are dehydrated.

Tablets don’t always stay down. Medications come in multiple forms, and every person responds differently to the different forms and routes. Some use ondansetron orally dissolving tablets (ODT) vaginally instead of orally. Others need a continuous infusion by a subcutaneous pump or IV. There are also transdermal patches, suppositories, and some medications can even be compounded into a cream or suppository. 

Not everything works the same for everyone and every pregnancy. Some medications are more effective in general, so be sure you have optimized dosing and scheduling before making a change to a new medication. Sometimes taking a different medication in the same category may have more benefit, like switching from ondansetron to granisetron or mirtazapine. Adding additional medications like olanzapine as needed or steroids for a few weeks can also help.

Further, most medications are more effective in higher amounts (e.g. taking 8 mg of Zofran/ondansetron instead of 4 mg) and if taken on a consistent schedule, not as needed (prn). For ondansetron, if taking a single 4 mg tablet every 6 hours doesn’t seem to be enough, ask to take 4 mg every 3 hours (the same as 8 mg every 6 hours). Ask also about different ways to take your medication to improve absorption such as vaginal use of ondansetron oral disintegrating tabs or a zofran pump, the granisetron patch, or IV medications. 

Taking medications during pregnancy can be very upsetting 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 are likely much greater risks. These issues 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. 

  • There is no research finding taking a higher dose of specifically ondansetron (but within the usual limit of 32 mg/day) increases the risk to the baby. 
  • Recent research on nearly a half million women taking ondansetron found no fetal risk. 
  • Only a few medications carry potential risks if taken for long periods of time (example: metoclopramide) so stopping medications while you are still sick will likely make you worse.
  • Our research and others have found that avoiding medications leads to more problematic outcomes for mother and baby.

You want to be heard and believed, so you can receive the treatment you need to protect you and your baby(s). We developed tools to help you have more objective conversations about symptoms and treatment.

  • Our HELP Score and Assessment tool (page 2 if currently pregnant) help you document your symptoms for your OB. Trending your HELP Score helps document changes in symptoms.
  • Our Treatment Algorithm helps guide them through the many options to give you relief.
  • Your OB can reach out to our clinical team for additional help.

More medication management tips:

See our Patient Treatment Guide for more details.

  • Scheduling your medications so you take them at exact intervals can greatly increase effectiveness. Some medications like ondansetron only work for about 6 hours, so skipping a dose or waiting 10 hours while you sleep usually results in worse symptoms.
  • Treat side effects. A daily stool softener is often necessary to control the constipation that is a side effect of serotonin medications.
  • Many need medications for months if not all of pregnancy. There is a very small to taking anything in very early pregnancy, but it's likely much less than the risk of poor nutrition and organ stress. The baby is largely developed by 8 weeks, meaning the risks greatly decrease.
  • Tell your doctor if you have existing health conditions, especially heart arrhythmias, as some medications can increase the risk especially if you do not have adequate electrolytes.
  • Always discuss all medication and changes with your doctor to avoid interactions and side effects.

Do not combine more than one medication in the same category (eg. Kytril and Zofran both affect serotonin and should not be taken together). Taking an antidepressant with serotonin medications could put you at a slight risk of serotonin syndrome.