When you're pregnant, every pill, drop, or supplement feels like a decision that could change your baby's life. That’s why knowing what to avoid isn’t just smart-it’s essential. Around 90% of pregnant women take at least one medication during pregnancy, but not all are safe. Some can cause serious harm, from birth defects to long-term developmental issues. The good news? You don’t have to guess. There are clear, science-backed warnings-and safer choices you can trust.
Medications That Can Harm Your Baby
Some drugs cross the placenta easily and interfere with your baby’s development, especially during the first trimester when organs are forming. The biggest red flags? Isotretinoin (Accutane), used for severe acne, carries a risk of over 25% for major birth defects-think skull, heart, and brain abnormalities. It’s so dangerous that the FDA requires women to enroll in the iPLEDGE program before getting it. If you’re planning pregnancy, stop this drug at least one month before trying to conceive.
Then there’s valproic acid, a common seizure medication. Studies show it increases the chance of major birth defects to 10.7%, compared to just 2.8% in the general population. It’s also linked to lower IQ and autism risk in children. If you have epilepsy, talk to your doctor about switching to lamotrigine or levetiracetam before pregnancy-both are much safer.
ACE inhibitors like lisinopril and ARBs like valsartan, used for high blood pressure, can cause fetal kidney failure, low amniotic fluid, and even death. These drugs are dangerous as soon as you’re pregnant. If you’re on them and thinking about conceiving, switch now. Your doctor can help you move to methyldopa or labetalol, which are proven safe during pregnancy.
Don’t forget about tetracycline antibiotics like doxycycline. They stain developing baby teeth yellow or gray and weaken bones. Fluoroquinolones like ciprofloxacin are linked to a nearly 2-fold higher risk of musculoskeletal problems. Even common NSAIDs like ibuprofen and naproxen can cause serious issues after 20 weeks: fetal kidney damage and dangerously low amniotic fluid. The FDA warns against using them at all after that point.
And then there’s warfarin (Coumadin). It crosses the placenta and can cause fetal warfarin syndrome-facial deformities, bone problems, and developmental delays. If you’re on warfarin and pregnant, you’ll need to switch to enoxaparin (Lovenox), which doesn’t cross the placenta and is much safer.
The Acetaminophen Controversy
For years, acetaminophen (Tylenol) was the go-to pain reliever during pregnancy. It was labeled safe, and doctors recommended it for headaches, fevers, and aches. But new research is changing that.
A 2021 JAMA Pediatrics study of 95,000 mother-child pairs found that prolonged acetaminophen use during pregnancy was linked to a 28.6% higher risk of ADHD and a 20.4% higher risk of autism spectrum disorder. The FDA issued a notice on September 22, 2025, advising women to use it only when necessary and to avoid daily or long-term use.
But here’s the catch: untreated high fever (above 102°F) increases the risk of neural tube defects by 8.2 times. So if you have a fever, not taking acetaminophen could be more dangerous than taking it. The key is short-term, low-dose use-no more than 3,000 mg a day, and only when you really need it. ACOG still lists it as the preferred option, but the CDC now says to consider avoiding it as a precaution. It’s not black and white. It’s about weighing risks and using it wisely.
Safer Alternatives for Common Symptoms
You don’t have to suffer through pregnancy discomforts without relief. There are safe, effective options for the most common issues.
Pain and fever: Stick with acetaminophen-but only when needed. Take 325-650 mg every 4-6 hours, not more than 3,000 mg total per day. Avoid combining it with other products that contain it, like cold medicines.
Allergies: Second-generation antihistamines are your best bet. Loratadine (Claritin), cetirizine (Zyrtec), and fexofenadine (Allegra) have been studied in over 2,000 pregnancies with no increased risk of birth defects. Take one daily as directed.
Nasal congestion: Start with saline sprays or a neti pot. If you need more, pseudoephedrine (Sudafed) is okay after the first trimester, but only at 30-60 mg every 4-6 hours, not more than 120 mg daily. Avoid it if you have high blood pressure-it can raise it by 5-10 mmHg.
Constipation: Fiber is your first line of defense. Aim for 25-30 grams a day from fruits, veggies, oats, and beans. Drink plenty of water. If you still need help, docusate sodium (Colace) at 100 mg twice daily is safe. Polyethylene glycol (Miralax) at 17g daily is also Category B and widely used without risk.
Depression and anxiety: Stopping antidepressants during pregnancy can raise your risk of preterm birth by 64% and low birth weight by 73%. Paroxetine (Paxil) carries a slightly higher risk of heart defects, so switch to sertraline or citalopram if possible. Untreated depression is a bigger threat than most medications. Work with your psychiatrist and OB-GYN to find the safest balance.
What to Do Before and During Pregnancy
Don’t wait until you’re pregnant to review your meds. If you’re planning to conceive, schedule a preconception visit. Bring a full list of everything you take-prescription, over-the-counter, herbs, and supplements. Many women don’t realize that things like melatonin, St. John’s wort, or high-dose vitamin A can be risky.
Use reliable resources. The MotherToBaby service, run by the Organization of Teratology Information Specialists, offers free, evidence-based advice. They’ve answered over 2.3 million questions annually. Their fact sheets are trusted by doctors and moms alike.
Keep a medication log. Write down what you take, when, and why. If you accidentally take something unsafe, don’t panic. Call your doctor or MotherToBaby immediately. Most exposures don’t lead to problems, but early action helps.
Check labels. The FDA’s Pregnancy and Lactation Labeling Rule (PLLR) replaced old letter categories (A, B, C, D, X) with clear summaries of risks. Look for sections titled “Pregnancy” and “Lactation” on drug labels. If you’re unsure, ask your pharmacist.
What About Breastfeeding?
Many of the same rules apply. Most medications pass into breast milk in tiny amounts, but some can still affect your baby. Acetaminophen and ibuprofen are generally safe for pain relief while nursing. Antihistamines like loratadine and cetirizine are preferred over diphenhydramine (Benadryl), which can make babies sleepy.
Avoid drugs like codeine, which can turn into morphine in your body and cause breathing problems in your baby. Also steer clear of certain antidepressants like paroxetine if you’re nursing, as it concentrates more in milk than others. Always check with your doctor before starting any new medication while breastfeeding.
When to Call Your Doctor
You don’t need to handle this alone. Call your provider if:
- You took a medication you weren’t supposed to, even once
- You’re unsure if a new OTC drug is safe
- You’re thinking about stopping or changing a prescription
- You have a fever above 102°F and aren’t sure how to manage it
- You’re planning pregnancy and take any chronic medication
There’s no shame in asking. The goal isn’t perfection-it’s safety. Your doctor wants to help you make the best choices for you and your baby.
What’s Changing in 2026?
Research is moving fast. The NIH is funding a $15 million project to find non-opioid pain options for pregnant women. ACOG will update its guidelines in 2026 to reflect new acetaminophen data. And the ABC Study-tracking 50,000 pregnant women across 15 countries-is expected to release its first neurodevelopmental results by late 2025.
For now, the message is clear: Be informed. Be cautious. Don’t avoid all meds-but don’t take them lightly. Every choice matters, and you have the power to make the safest ones.
Is it safe to take Tylenol while pregnant?
Tylenol (acetaminophen) is still considered the safest pain reliever during pregnancy, but only when used at the lowest effective dose for the shortest time. Long-term or daily use has been linked to a higher risk of ADHD and autism in children, according to a 2021 JAMA Pediatrics study. The FDA updated its guidance in September 2025 to recommend minimizing use, especially for mild symptoms. Use no more than 3,000 mg per day, and avoid combining it with other products that contain acetaminophen.
Can I take ibuprofen during pregnancy?
No, ibuprofen and other NSAIDs like naproxen should be avoided after 20 weeks of pregnancy. The FDA issued a warning in 2020 because these drugs can cause fetal kidney problems and dangerously low amniotic fluid levels. Even before 20 weeks, they’re not the first choice-acetaminophen is safer. If you need pain relief, skip ibuprofen and reach for Tylenol instead.
What’s the safest allergy medicine during pregnancy?
Loratadine (Claritin), cetirizine (Zyrtec), and fexofenadine (Allegra) are all considered safe during pregnancy. These second-generation antihistamines have been studied in thousands of pregnancies with no increased risk of birth defects. Avoid first-generation ones like diphenhydramine (Benadryl), which can cause drowsiness in both you and your baby. Take one daily as directed.
Are antidepressants safe during pregnancy?
Some are, and some aren’t. Paroxetine (Paxil) carries a slightly higher risk of heart defects, so it’s usually avoided. Sertraline and citalopram are preferred because they’ve been studied more and show lower risks. But untreated depression can lead to preterm birth, low birth weight, and developmental delays. The key is working with your doctor to find the safest medication at the lowest effective dose-not stopping without guidance.
What should I do if I took a risky medication before knowing I was pregnant?
Don’t panic. Most exposures don’t lead to birth defects. Call your doctor or contact MotherToBaby (1-866-626-6847) for free, expert advice. They’ll review what you took, when, and how much, and help you understand your actual risk. Many women have taken something unsafe early on and gone on to have healthy babies. The goal is to avoid further exposure and monitor closely going forward.
Is it safe to take prenatal vitamins with extra ingredients?
Not always. Many prenatal vitamins include added herbs, probiotics, or high doses of vitamin A, which can be harmful. Stick to a basic prenatal with folic acid, iron, and DHA. Avoid those with high-dose vitamin A (over 5,000 IU), as too much can cause birth defects. Always check the label and talk to your provider before taking anything extra.
Next Steps: What to Do Today
- Make a list of every medication, supplement, and herb you take-prescription, OTC, and natural.
- Check each one against the FDA’s Pregnancy and Lactation Labeling Rule or ask your pharmacist.
- If you’re planning pregnancy, schedule a preconception visit to review your meds.
- If you’re already pregnant, don’t stop or start anything without talking to your provider.
- Bookmark MotherToBaby.org and save their number: 1-866-626-6847.
Pregnancy isn’t about being perfect. It’s about being informed. You’ve got this.