The Truth About Drugs and Supplements While Breastfeeding

Two years ago, a researcher who specializes in the safety of breast milk was in the midst of breastfeeding her own child when she experienced a serious bout of postpartum depression. She had a televisit with her doctor, who refused to write her a prescription for antidepressant medications as long as she was still breastfeeding, even though the drugs are considered safe to take during pregnancy and breastfeeding. 

“A lot of times, [the] health [of the new mother] isn’t prioritized as much as that of the infant. And that’s something that we really worry about,” says Kaytlin Krutsch, PharmD, a pharmacotherapy specialist with the InfantRisk Center at Texas Tech University Health Sciences Center, a group of researchers that studies the effects of drugs and supplements on breast milk. The center also provides resources for parents. 

It’s not just the doctors who are cautious. “Moms are really afraid, sometimes [of] even taking their antibiotics,” she explains. “Gosh, that’s so sad to me because it’s good for them. It’s fairly safe for the infant. And I can’t imagine just choosing to be sick and to deal with it. There’s a lot of literature out there that says that moms feel like they need to be a good mother, and to do that, they have to sacrifice their own health.”

It’s sometimes true that neither physicians nor mothers know as much as they may like about drugs and supplements — how they enter breast milk and in what doses and what side effects those substances can have on the babies who consume breast milk. However, over the past decade, researchers like Krutsch have been systematically studying those drugs and supplements to provide better guidance. 

In addition to studying different types of drugs one by one, she and her team have compiled existing evidence on many drugs and created a ranking system that describes the relative risk of using a treatment while breastfeeding and the research strength about them. The team has developed resources for doctors as well as an app for parents, MommyMeds, in which they can use to can learn about the safety of drugs and supplements by scanning their barcodes.

Krutsch says throughout her research she’s been surprised by how many treatments she’s found to be safe. “I would have thought that the risk would be much higher with a lot of these medications. The reality is our body does a really good job at protecting the infant. Most of [the treatments] pass through [to the breast milk] in very, very low degrees.” 

How Do Drugs and Supplements Get Into Breast Milk?

Whether and how much of a substance enters your breast milk depends on two main factors: the drug’s chemistry – some are more readily absorbed than others; and the timing of taking it.

Chemistry

Drugs and supplements all have different chemical characteristics. Some get absorbed by water and others by fats. Some bind to certain proteins in your blood while others float freely. These characteristics determine how and where the drugs move through your body. Drugs that are lipophilic, attracted to fats, and protein-bound are more likely than others to end up in your breast milk in higher concentrations than those that aren’t.

But there’s more than chemistry going on. Timing also plays a big role. 

Timing

Sonal Patel, MD, a pediatrician and neonatologist with a private practice specializing in helping parents and infants through the baby’s first months, explains that in the first few days after giving birth, the mother isn’t producing that much milk. “Even if you’re using drugs that are easily passed into the milk, there’s not enough of [them] in there.” After about four days, she explains, the alveolar cells around the breast-milk ducts widen to allow you to pass antibodies that fight infections on to your baby. After Day 10, those cells swell up and close again, limiting the amount of drug that can be passed into the breast milk. However, at this point, moms are producing more breast milk than they were right after childbirth.

Many women who have cesarean sections (C-sections) or experience especially painful vaginal births are prescribed opioids. Patel explains that during the early days after giving birth, these drugs are unlikely to affect your infant. After that, your physician will likely transition you to another painkiller like Tylenol or Advil, because, starting then, the opioids can get into your breast milk and dangerously slow your baby’s breathing or make it difficult for them to latch. If those drugs aren’t effective enough against your pain, it’s time to go back to the doctor for an evaluation. “There might be something else going on that hasn’t been addressed,” says Patel. 

Common Concerns, Side Effects of Drugs on Breast Milk

Cold medication

Ingredients that Patel and Krutsch recommend nursing parents limiting are found in cough suppressants. These drugs, including Robitussin Cough (dextromethorphan) and Vicks 44 Cough and Cold (pseudoephedrine) can be transferred through breast milk and slow your baby’s breathing, explains Krutsch. Patel also recommends staying away from anything containing the painkiller codeine and, again, pseudoephedrine, which is also found in Sudafed, because it can lower your milk production. 

Alcohol

It’s well-known that alcohol is usually off-limits for pregnant people, but Patel says that it’s ok to have a drink when breastfeeding. The difference, she explains, is in how that alcohol reaches your baby. When you’re pregnant, the alcohol goes to the baby right away, but when you’re breastfeeding, the alcohol gets metabolized in your liver before it makes its way to your breast. If you’ve imbibed enough to feel intoxicated, more alcohol may make it into your breast milk so she does recommend pumping and dumping (pumping your breast milk out, but not giving it to your baby).

Supplements

You may want the benefits from some pills you take to move into your breast milk. Luckily, some important vitamins do. “If you’re breastfeeding,” says Patel, “please, please, please take prenatal vitamins.” In addition to providing your baby with an extra boost, it’s also helping you “reestablish and rejuvenate your own nutrients.” 

On the other hand, since vitamins and herbal supplements are not regulated by the Food and Drug Administration (FDA), she recommends paying close attention to how you and your baby respond. Patel herself tried an herbal supplement to boost milk production while she was breastfeeding, but she noticed that it caused both her and her baby excess gas. She stopped taking it. 

The app MommyMeds also offers information on the safety of many supplements.

Allergy medications

Antihistamines were once thought to reduce your supply of breast milk, but Krutsch says that’s not the case. The receptors for the drugs “just aren’t in your breasts,” she says. It’s ok to take over-the-counter allergy medicines like Allegra, Claritin and Zyrtec while breastfeeding. 

Antidepressants

Many nursing and pregnant people, and even their doctors, worry about how antipsychotic medicines might affect infants. Because of that fear, many of those drugs have been studied more frequently than others. “SSRIs [selective serotonin reuptake inhibitors], a common type of antidepressant medicine, are over and over again proven to be safe with pregnancy,” says Patel. “And the rule of thumb is that if it’s safe in pregnancy, it’s probably safe in breast milk.” She also emphasizes the importance of remembering the physical and mental health needs of the woman doing the breastfeeding. 

A 15-year study in JAMA, published this year, showed that taking SSRIs during pregnancy did not increase the likelihood of an infant developing ADHD (attention-deficit/hyperactivity disorder), autism spectrum disorder or preterm birth.

Where to Get More Info, and How to Talk to Your Doctor About Medicines and Breast Milk

When you’re at the pharmacy, you can pull up the MommyMeds app and scan any product you’re considering. It’ll give you a risk score from L1 to L5, representing how safe the treatment is for you and your baby and how confident researchers are with the level of existing evidence. 

• L1 Safest: Extensive evidence demonstrating no adverse effects on the infant.

• L2 Safer: Limited evidence without an increase in adverse effects on the infant.

• L3 Probably Safe: No studies, but expert opinion suggesting safety. Risk to the infant is possible, and further evaluation must be taken to consider individual situations.

• L4 Possibly Hazardous: Positive evidence or expert opinion of risk to the infant or milk production.

• L5 Hazardous: Significant and documented risk to the infant. Contraindicated.

The National Institutes of Health (NIH) also has a database called LactMed, which offers detailed information about individual drugs.

Both Patel and Krutsch agree that the most important thing you can do is to be open with your physician about the medicines, vitamins and supplements you are using during breastfeeding. 

“Despite how much we want to be able to make evidence-based decisions, whenever you don’t have evidence, you still have to make a decision,” Krutsch says. Talking it through with your physician can help you do so. The InfantRisk Center also provides a call center to answer your questions.

Lastly, Krutsch emphasizes that the benefits of breastfeeding often outweigh the minor risks of exposing your baby to medicines. “Whenever you’re making that risk-benefit evaluation, [remember that] breastfeeding is so beneficial to moms and to babies.”