You are pregnant. You ask, “Can I take my medication?” If you ever heard, “it depends…”, you are not alone. Things affect people differently.

So, what is going on?

This has to do with genetics. Genetics is the study of genes. Genes are a part of our DNA. Genes tell your cells what to do. Genes tell us how to process the world around us.

What Do We Mean by “Exposures”?

Anything that comes into contact with your body is an exposure. Food, drinks, and drugs are exposures. Getting sick is an exposure. Stress is an exposure too.

Exposure questions can feel like a lot!

Why Can the Same Exposure Affect People Differently?

People can have the exact same exposure. Their bodies might handle it differently. That is because of metabolization. Metabolization is how fast our bodies break down an exposure. This affects how long an exposure stays in your body.

Genes affect how your body breaks down something. Genes shape how the body responds to an exposure.

What Are Some Examples?

1. Caffeine and Pregnancy

Let us say that you got coffee with a friend at 3:00 pm. You might fall asleep easily that night. Your friend might feel jittery after half a cup. You and your friend have different responses to the same amount of caffeine. That difference comes from your genetics. Your genes might metabolize caffeine faster. This is why you fell asleep easily. Your friend might metabolize caffeine more slowly. This is why your friend felt jittery.

Genes affect how fast caffeine is broken down. This is why caffeine during pregnancy rules are careful. It is suggested that you get 200 mg of caffeine (or less) per day during pregnancy. The rules are there to protect those that process caffeine more slowly.

The end message? There are rules about pregnancy. These rules are broad. Your experience might be different than what the rules say. For more information on caffeine, click here: https://mothertobaby.org/fact-sheets/caffeine-pregnancy/

2.  General Anesthesia and Breastfeeding

Let us say that your dentist tells you to get your wisdom teeth removed. This is a surgery. For this, you will get general anesthesia. General anesthesia is a mix of medication. This is given so that you can fall asleep for a procedure.

General anesthesia is broken down fast. Your friend got her wisdom teeth removed last year. She woke up 2 minutes after her surgery was done. You woke up 5 minutes after your surgery was done.  

It takes some time for you to feel normal after general anesthesia. You might feel a little loopy right after general anesthesia. Your friend felt normal about 1 hour after her surgery. You felt normal about 3 hours after your surgery. You and your friend react differently to general anesthesia.

Genes affect how fast something is broken down by the body. This is why the rules for getting general anesthesia while breastfeeding are careful. It is suggested to wait to breastfeed if you still feel loopy. This means waiting to breastfeed until you feel “back to normal.”

The end message? Everyone needs a different amount of time to break down general anesthesia. The best time to breastfeed is different for everyone. For more information on general anesthesia, click here: https://mothertobaby.org/fact-sheets/general-anesthesia-pregnancy/

What Does This Mean for Pregnancy and Breastfeeding Advice?

People are different. People have different genes. This means that people break down exposures in a different way.

Most recommendations try to:

• Lower the chance of any possible problems;
• Help people who might break things down more slowly;
• Balance safety with needs.

Final Thoughts

What happens to your body during pregnancy and breastfeeding can feel so hard. It can feel harder when your body reacts differently than what is expected. If you compare yourself to others, you should know you did nothing wrong. You did not need to know better. You did not fail.

You might feel overwhelmed or worried about an exposure. You might feel frustrated if you get advice that clashes. Talking to MotherToBaby can help you get information without judgment.

Do you enjoy protein shakes, adding protein powder to your smoothies, or using pre-workout mixes with protein? My friend, Emily, is currently in her first trimester and loves getting extra protein. Before she got pregnant, she started power lifting, which also came with extra protein supplementation. Once she got pregnant, Emily asked me, like so many others in her position, if she could continue her protein supplementation during pregnancy and when breastfeeding.

With any pregnancy, there is a 3% chance of developing a birth defect.  So I looked into protein supplementation to see if it changes the risk for birth defects, side effects during breastfeeding, or any other issues. That way, Emily could make a well-informed decision for her health and the health of her family.

Many of these protein products contain types of protein that are also found in everyday foods and even in breast milk. Everyone needs a certain amount of protein every day as a part of a balanced diet. However, there are certain reasons why someone might have a specific daily protein intake goal. Like Emily, many people are interested in having more protein to build muscle. There are other health conditions, like phenylketonuria (PKU), that affect how much protein you should get in your diet. Ultimately, it is very important for you to review your personal daily protein intake goals with your healthcare team to make sure your health is supported.

Not every protein supplement has been well studied, so information on using them during pregnancy or breastfeeding is limited. In addition, many protein powders and drinks also include other ingredients, such as added vitamins or herbal products. For more information on herbal products, check out our fact sheet on here:  https://mothertobaby.org/fact-sheets/herbal-products-pregnancy/.

Supplements are regulated differently than prescription drugs. Even though the United States Food and Drug Administration (FDA) regulates supplements, the FDA doesn’t check every product for safety or effectiveness before it goes on the shelf. This means some protein powders might contain some unknown or unlisted ingredients.

So before adding that extra scoop of protein powder, take some time to figure out if protein supplementation is right for you.

How Much Protein Do You Need?

How much protein you need depends on different factors, such as age, activity level, and health. Some proteins have a daily recommended dietary allowance (RDA). The RDA depends on a person’s weight. You, most likely, get some amount of protein from your diet naturally. It’s important to take your diet into consideration when trying to figure out how much protein you should be having. Because there are so many things to consider, it’s recommended to talk with your healthcare team to make sure you are meeting your nutritional needs. Getting the right amount of protein for you is not expected to increase the risk for issues during pregnancy or side effects during breastfeeding.

What are the typical amino acids in protein supplements?

Most protein powders contain many amino acids. Amino acids are the building blocks of protein. The list below may not include everything that might be found in your protein powder. Since not every amino acid has an RDA, here is a list of the known amino acids with an RDA. It’s always a good idea to double check with your healthcare team on what your specific protein intake goals are.

• Cysteine & Methionine*
  • RDA during pregnancy: 25 mg/kg

  • RDA during breastfeeding: 26 mg/kg

• Isoleucine
  • RDA during pregnancy: 25 mg/kg

  • RDA during breastfeeding: 30 mg/kg

• Leucine
  • RDA during pregnancy: 56 mg/kg

  • RDA during breastfeeding: 62 mg/kg

• Lysine

  • RDA for adults: 12 mg/kg

• Threonine
  • RDA during pregnancy: 26 mg/kg

  • RDA during breastfeeding: 30 mg/kg

• Tryptophan

  • RDA for adults: 3.5 mg/kg

• Valine
  • RDA for pregnancy: 31 mg/kg

  • RDA for breastfeeding: 35 mg/kg

*Note: The RDA for methionine and cysteine is combined.

What About Other Ingredients?

Often, protein powders can have other ingredients in addition to the protein. Again, check the label on your specific products, as they can vary.

• Caffeine: For more information on caffeine, check out our fact sheet: https://mothertobaby.org/fact-sheets/caffeine-pregnancy/
• Collagen: There aren’t any studies that look at the use of collagen as a supplement during human pregnancy or breastfeeding.
• Creatine: Creatine is naturally found in the body and in breastmilk. There aren’t any studies that look at the use of creatine as a supplement during human pregnancy or breastfeeding.

So What Now?

Emily realized that since there is not a lot of information on protein supplementation during pregnancy and breastfeeding. The best next step for her was to chat with her healthcare team about what would best support her health and pregnancy. Some providers on her healthcare team include her primary care provider, her nurse-midwife, her nutritionist, and her endocrine specialist. Emily decided that she’s even going to talk to a lactation consultant now so she can have time to prepare for breastfeeding. She knew how to measure how much protein she was getting in her protein powder, but she needed help estimating how much protein she naturally gets in her diet as well.

Have more questions about supplements or other exposures during pregnancy or breastfeeding? Talk to a teratogen-information specialist at MotherToBaby.org.

References

Elango R. & O Ball, R. 2016. Protein and amino acid requirements during pregnancy. Advances in Nutrition, 7(4): 839-844. https://doi.org/10.3945/an.115.011817.

Food and Nutrition Board. 2005. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. Washington, DC: The National Academies Press.

National Research Council. 1989. Recommended dietary allowances: 10th Edition. Washington, DC: The National Academies Press. https://doi.org/10.17226/1349.

U.S. Food & Drug Administration. 2025. Infant formula. https://www.fda.gov/food/resources-you-food/infant-formula

Ever wonder if you’re getting the right amount of vitamins and minerals during pregnancy or breastfeeding? Like Goldilocks, you don’t want too little or too much — you want just right. Even though it took Goldilocks multiple tries to find the right size chair and the right bowl of porridge, it doesn’t have to take you that long to find the right amount of vitamins and minerals for you!

Everyone has a 3% chance of developing a birth defect during pregnancy. Getting the right amount of vitamins and minerals FOR YOU is not expected to increase the risk for issues during pregnancy and it is not expected to increase the risk for side effects during breastfeeding.

Most people in the United States get some vitamins and minerals in their diet. However, your healthcare provider might have specific goals for you to get certain amounts of a vitamin or mineral, particularly during pregnancy or breastfeeding. One way to get that extra support during pregnancy is to take a prenatal vitamin that has at least 600 mcg of folic acid (for more information on folic acid, check out our fact sheet: https://mothertobaby.org/fact-sheets/folic-acid/.

If you also take other supplements, or drink juices and shakes that list vitamins on the nutrition label, you could be getting more than you need. Reading nutrition labels help you track how many vitamins and minerals you are getting into your body.

DRIs: What Are They?

DRI stands for Dietary Reference Intake. DRIs are a list of nutritional values that are used to guide people to make sure they are getting a well-balanced diet that supports their health. There are a couple different DRIs, but the ones that are used in this blog are called RDA and UL.

• RDA (Recommended Dietary Allowance): The average daily amount of a vitamin or mineral that most people need.
• UL (Tolerable Upper Limit): The maximum safe amount you can take in a day without raising the risk of side effects.

Not every vitamin and mineral has an RDA or UL. For the vitamins and minerals that do have DRIs, it’s typically recommended to aim for the RDA every day, unless your healthcare provider tells you differently. For the ones that do have DRIs, they can change based on age or when pregnant or breastfeeding. You will also get many nutrients from your regular diet, so supplements are intended to help fill in gaps — not overload your system.

Why Supplement Safety Matters

Supplements are regulated differently than prescription drugs. Even though the United States Food and Drug Administration (FDA) regulates supplements, the FDA doesn’t check every product for safety or effectiveness before it goes on the shelf. This means labels may not always tell the whole story, and some products could include unknown or unlisted ingredients.

Talk to your healthcare provider before taking a supplement to make sure you are getting the right amount of vitamins and minerals to support your health. You can contact MotherToBaby to get more information on a supplement you are considering.

Have more questions about supplements or exposures during pregnancy or breastfeeding? You can reach a teratogen-information specialist at MotherToBaby.org.

DRIs for Vitamins and Minerals During Pregnancy and Breastfeeding:

Name	RDA-pregnancy	UL-pregnancy	RDA-lactation	UL-lactation
Biotin	14+ years old: 30 mcg	Unknown	14+ years old: 35 mcg	Unknown
Boron	Unknown	14-18 years old: 17 mg 19+ years old: 20 mg	Unknown	14-18 years old: 17 mg 19+ years old: 20 mg
Calcium	14-18 years old: 1,300 mg 19+ years old: 1,000 mg	14-18 years old: 3,000 mg 19+ years old: 2,500 mg	14-18 years old: 1,300 mg 19+ years old: 1,000 mg	14-18 years old: 3,000 mg 19+ years old: 2,500 mg
Choline	14+ years old: 450 mg	14-18 years old: 3,000 mg 19+ years old: 3,500 mg	14+ years old: 550 mg	14-18 years old: 3,000 mg 19+ years old: 3,500 mg
Chromium	14-18 years old: 29 mcg 19+ years old:     30 mcg	Unknown	14-18 years old: 44 mcg 19+ years old: 45 mcg	Unknown
Copper	14+ years old: 1,000 mcg	14-18 years old: 8,000 mcg 19+ years old: 10,000 mcg	14+ years old: 1,300 mcg	14-18 years old: 8,000 mcg 19+ years old: 10,000 mcg
Folic Acid	14+ years old: 600 mcg DFE	14-18 years old: 800 mcg 19+ years old: 1,000 mcg	14+ years old: 500 mcg DFE	14-18 years old: 800 mcg 19+ years old: 1,000 mcg
Iodine	14+ years old: 220 mcg	14-18 years old: 900 mcg 19+ years old: 1,100 mcg	14+ years old: 290 mcg	14-18 years old: 900 mcg 19+ years old: 1,100 mcg
Iron	14+ years old: 27 mg	14+ years old: 45 mg	14-18 years old: 10 mg 19+ years old:  9 mg	14+ years old: 45 mg
Magnesium	14-18 years old: 400 mg 19-30 years old: 350 mg 30+ years old:  360 mg	9+ years old: 350 mg*	14-18 years old: 360 mg 19-30 years old: 310 mg 30+ years old:  320 mg	9+ years old: 350 mg*
Manganese	14+ years old: 2.0 mg	14-18 years old: 9 mg 19+ years old: 11 mg	14+ years old: 2.6 mg	14-18 years old: 9 mg 19+ years old: 11 mg
Molybdenum	14+ years old: 50 mcg	14-18 years old: 1,700 mcg 19+ years old: 2,000 mcg	14+ years old: 50 mcg	14-18 years old: 1,700 mcg 19+ years old: 2,000 mcg
Niacin	14+ years old: 18 mg NE	14-18 years old: 30 mg 19+ years old: 35 mg	14+ years old: 17 mg NE	14-18 years old: 30 mg 19+ years old: 35 mg
Omega-3 fatty acids	14+ years old: 1,400 mg	Unknown	14+ years old: 1,300 mg	Unknown
Pantothenic acid	14+ years old:   6 mg	Unknown	14+ years old: 7 mg	Unknown
Phosphorus	14-18 years old: 1,250 mg 19+ years old:  700 mg	14+ years old: 3,500 mg	14-18 years old: 1,250 mg 19+ years old:  700 mg	14+ years old: 4,000 mg
Potassium	14-18 years old: 2,600 mg 19+ years old: 2,900 mg	Unknown	14-18 years old: 2,500 mg 19+ years old: 2,800 mg	Unknown
Riboflavin	14+ years old: 1.4 mg	Unknown	14+ years old: 1.6 mg	Unknown
Selenium	14+ years old: 60 mcg	14+ years old: 400 mcg	14+ years old: 70 mcg	14+ years old: 400 mcg
Thiamin	14+ years old: 1.4 mg	Unknown	14+ years old: 1.4 mg	Unknown
Vitamin A	14-18 years old: 750 mcg RAE 19+ years old:  770 mcg RAE	14-18 years old: 2,800 mcg 19+ years old: 3,000 mcg	14-18 years old: 1,200 mcg RAE 19+ years old: 1,300 mcg RAE	14-18 years old: 2,800 mcg 19+ years old: 3,000 mcg
Vitamin B6	14+ years old: 1.9 mg	14-18 years old: 80 mg 19+ years old: 100 mg	14+ years old: 2.0 mg	14-18 years old: 80 mg 19+ years old: 100 mg
Vitamin B12	14+ years old: 2.6 mcg	Unknown	14+ years old: 2.8 mcg	Unknown
Vitamin C	14-18 years old: 80 mg 19+ years old:     85 mg	14-18 years old: 1,800 mg 19+ years old: 2,000 mg	14-18 years old: 115 mg 19+ years old: 120 mg	14-18 years old: 1,800 mg 19+ years old: 2,000 mg
Vitamin D	14+ years old: 15 mcg (600 IU)	14+ years old: 100 mcg (4,000 IU)	14+ years old: 15 mcg (600 IU)	14+ years old: 100 mcg (4,000 IU)
Vitamin E	14+ years old: 15 mg	14-18 years old: 800 mg 19+ years old: 1,000 mg	14+ years old: 19 mg	14-18 years old: 800 mg 19+ years old: 1,000 mg
Vitamin K	14-18 years old: 75 mcg 19+ years old:     90 mcg	Unknown	14-18 years old: 75 mcg 19+ years old:     90 mcg	Unknown
Zinc	14-18 years old: 12 mg 19+ years old:     11 mg	14-18 years old: 34 mg 19+ years old: 40 mg	14-18 years old: 13 mg 19+ years old:     12 mg	14-18 years old: 34 mg 19+ years old: 40 mg

(This chart has last been updated on 9/29/2025)

*Note: The UL for magnesium only applies to supplements. You can safely get more from food since the RDA includes dietary magnesium.

Where Can I Find More Information?

MotherToBaby has fact sheets on a couple of the common vitamins and minerals that might be found in a multivitamin or a prenatal vitamin. For more detailed information on a specific vitamin or mineral, check out our fact sheets below:

• Folic acid – https://mothertobaby.org/fact-sheets/folic-acid/

• Iodine – https://mothertobaby.org/fact-sheets/iodine-pregnancy/
• Iron – https://mothertobaby.org/fact-sheets/iron/
• Vitamin A – https://mothertobaby.org/fact-sheets/vitamin-a/
• Vitamin B12 – https://mothertobaby.org/fact-sheets/vitamin-b12/
• Vitamin C – https://mothertobaby.org/fact-sheets/vitamin-c/
• Vitamin D – https://mothertobaby.org/fact-sheets/vitamin-d/
• Vitamin E – https://mothertobaby.org/fact-sheets/vitamin-e/
• Vitamin K – https://mothertobaby.org/fact-sheets/vitamin-k/
• Zinc –   https://mothertobaby.org/fact-sheets/zinc/

References

National Academies of Sciences, Engineering, and Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. https://doi.org/10.17226/6015.

National Institutes of Health Office of Dietary Supplements. 2025. Dietary Supplement Fact Sheets. U.S. Department of Human and Health Services. https://ods.od.nih.gov/factsheets/list-all/

Office of Disease Prevention and Health Promotion. 2023. Dietary Reference Intakes. U.S. Department of Human and Health Services. https://odphp.health.gov/our-work/nutrition-physical-activity/dietary-guidelines/dietary-reference-intakes

The runs, the trots, the green apple quickstep. You have heard all the nicknames for it, but even hearing something as cute as “bubble guts” does not make diarrhea any better, especially during pregnancy or breastfeeding.

Just last week, I got a call from someone in a panic: “Leah, it is really bad. I am so uncomfortable. I thought you were supposed to get constipated during pregnancy.”

That caller was not wrong – constipation can be common during pregnancy. Hormones like prostaglandins – which help signal to your intestines that it is time to move things along – tend to slow down during pregnancy. Even still, constipation does not always happen.

Food poisoning, viral illnesses (like COVID-19), and chronic conditions (like IBS or Crohn’s disease) can all cause diarrhea, even during pregnancy or breastfeeding. No matter where it comes from, everyone asks the same question, “How do I make this stop?” Before we answer that question, let us talk about what is really going on when you have diarrhea.

Diarrhea: What is Actually Going On?

What makes diarrhea different from your regular poops? Diarrhea is when you have loose or watery stools (poops). Diarrhea can look brown, but it can sometimes look yellow, mucous-y, or mostly clear. Some other symptoms of diarrhea can include abdominal cramping, feeling the urge “to go,” or gas. Diarrhea can be caused by lots of different things. Sometimes, diarrhea can be caused by food or drinks (such as food poisoning, contaminated water, or allergies to food products like lactose). Diarrhea can also be caused by other conditions (such as viral infections, conditions that affect the GI system, or medications). When you have diarrhea, your body gets rid of water and electrolytes much faster than usual. It is always important (but especially when you have diarrhea) to wash your hands for at least 20 seconds with soap and water after going to the bathroom. This helps prevent the spread of infections.

What Does That Mean if I am Pregnant or Breastfeeding?

One of the main concerns with diarrhea is the risk of dehydration. If you are severely dehydrated during pregnancy, this can increase the risk of some pregnancy-related issues, like oligohydramnios (not enough amniotic fluid). If you are severely dehydrated while breastfeeding, this can lower the amount of breastmilk that you produce. Yellow or dark urine, being unable to urinate, feeling dizzy or faint, and feeling thirsty are some signs of dehydration. Typically, rehydration includes giving yourself more water and more electrolytes to replace the water and electrolytes that you lost from the diarrhea. If you are experiencing dehydration, you should check with your healthcare team about what you can do to rehydrate yourself.

Over-The-Counter Options

Over-the-counter medications might be a helpful way to treat diarrhea, depending on the situation. Let us explore what we know about the common over-the-counter antidiarrheal medications: loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol). For more information on these types of medications, or any others, contact a specialist at MotherToBaby.

Loperamide

Loperamide is a common over-the-counter antidiarrheal. Loperamide works by attaching to certain receptors in your intestines to say, “please don’t move things along so much.” Taking loperamide slows the movement in your intestines, which slows down how often you have a bowel movement.

When you take loperamide as directed, most of the medication stays in your intestines and it is not expected that you would absorb a lot of the loperamide into your bloodstream where it can then reach the baby. Loperamide, however, is not well-studied in pregnancy and it is not known if taking loperamide as directed during pregnancy changes the chance of miscarriage or pregnancy-related issues, like preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces at birth). One study showed that taking loperamide during the first trimester of pregnancy might increase the chance of birth defects and another study did not find an increased chance.

Because there is not a lot of information about using loperamide during pregnancy, you and your healthcare provider may need to decide what’s best for you. Treating diarrhea is important especially to prevent dehydration, but it is also important to consider the limited information we have about this medication in pregnancy.

Loperamide does pass into breastmilk. If you decide to take loperamide while breastfeeding, your infant will get a very small exposure. It is not expected that exposure to loperamide through breastmilk will lead to side effects in the infant.

Bismuth Subsalicylate

Bismuth subsalicylate is another over-the-counter medication that is commonly used for diarrhea.  Some common names for bismuth subsalicylate are Pepto-Bismol, Kaopectate, and BisBacter. Bismuth subsalicylate works by slowing prostaglandins down (which helps to lower inflammation and slow intestinal movements) and encouraging your body to reabsorb water from the intestines (which helps make bowel movements less watery). Bismuth subsalicylate turns into two components in the body: bismuth and salicylate.

Most of the bismuth stays in your intestines and it is not expected that you would absorb a lot of the bismuth into your bloodstream where it can reach the baby.

However, salicylate can be absorbed into your bloodstream. Taking something that has salicylate in it during pregnancy (like bismuth subsalicylate or NSAIDS, like aspirin or ibuprofen), can cause problems with how the baby’s heart works or how baby’s kidneys work which may cause oligohydramnios (not enough amniotic fluid around the baby) and poor lung development. It may also cause bleeding concerns for you.  Because of this, it is generally recommended to avoid any medications that have salicylate in them, especially in the second and third trimester of your pregnancy.

If you take something that has salicylate in it while breastfeeding (like bismuth subsalicylate or NSAIDS, like aspirin or ibuprofen), some salicylate will most likely be present in your breastmilk. There is concern about giving salicylate directly to an infant. Infants tend to metabolize (or process) salicylate slower than adults do. Reye’s syndrome, a rare condition involving brain swelling and liver damage, can happen if an infant is recovering from a viral infection and is exposed directly to salicylate.

For more information on bismuth subsalicylate, check out our “Managing Tummy Troubles During Pregnancy” blog.

The Bottom Line – No Pun Intended

Diarrhea is uncomfortable, exhausting, and when you are pregnant or breastfeeding, often stressful on a whole new level. You should not have to choose between feeling better and worrying about your baby.

Staying hydrated is always a priority, but when symptoms don’t improve, medications might be helpful, depending on your situation. As always, if you notice any changes in your body during pregnancy or in your infant during breastfeeding (like an increase in stools, or a change in color or consistency of stools), you can reach out to a healthcare provider for guidance on what to do next.

And remember, if you ever feel unsure about an exposure, medication, or symptom during pregnancy or breastfeeding, you don’t have to figure it out alone. Evidence-based guidance can bring peace of mind — even on the days your stomach has other plans. Contact a MotherToBaby specialist to talk to someone about your concerns.

Good luck and I hope your tummy feels better soon!

References

https://www.acog.org/womens-health/faqs/problems-of-the-digestive-system

https://www.acog.org/womens-health/faqs/morning-sickness-nausea-and-vomiting-of-pregnancy