Medications to Avoid While Pregnant: Safety Warnings and Safe Alternatives

When you're pregnant, every pill, drop, or supplement feels like a decision that could change your baby’s life. You want to feel better-whether it’s a headache, a stuffy nose, or heartburn-but you’re terrified of doing something that might hurt your baby. The truth is, medications to avoid during pregnancy aren’t always obvious. Some are sold over the counter. Others are prescriptions you’ve taken for years. And some, like acetaminophen, are the very things you’ve been told are safe-until now.

What’s Actually Dangerous During Pregnancy?

Not all medications are created equal when it comes to pregnancy. Some are outright dangerous, especially during the first trimester when your baby’s organs are forming. Others become risky later on, even if they seemed fine earlier. The FDA’s old letter categories (A, B, C, D, X) are gone. Now, labels give real-world details: what the risks are, when they happen, and what the data shows.

Here’s what you need to know about the most common dangerous drugs:

• NSAIDs (ibuprofen, naproxen, aspirin): These are common pain relievers, but starting at 20 weeks, they can cause your baby’s kidneys to fail and reduce amniotic fluid. The FDA warned about this in 2020. Even if you took them early in pregnancy without issues, avoid them after 20 weeks unless your doctor says otherwise.
• ACE inhibitors and ARBs (lisinopril, valsartan): Used for high blood pressure, these can cause severe kidney damage, low amniotic fluid, and even death in the baby. If you’re on these and find out you’re pregnant, stop immediately and call your provider. There are safer blood pressure meds for pregnancy.
• Isotretinoin (Accutane): This acne drug has a greater than 25% chance of causing serious birth defects-cleft palate, heart problems, brain abnormalities. It’s so dangerous that the FDA requires a strict program (iPLEDGE) just to prescribe it. If you’re trying to get pregnant, stop this at least one month before conception.
• Valproic acid: Used for epilepsy and bipolar disorder, this drug increases the risk of major birth defects to nearly 11%, compared to about 3% in the general population. If you have epilepsy, talk to your neurologist before getting pregnant-you may need to switch to lamotrigine or levetiracetam.
• Tetracyclines (doxycycline): These antibiotics can permanently stain your baby’s teeth and slow bone growth. Avoid them entirely during pregnancy.
• Warfarin (Coumadin): This blood thinner can cross the placenta and cause fetal warfarin syndrome, leading to facial deformities and bone issues. If you’re on warfarin and planning pregnancy, switch to heparin (like Lovenox) before conception. Heparin doesn’t cross the placenta.

The Acetaminophen Dilemma: Still Safe or Not?

For decades, acetaminophen (Tylenol) was the go-to pain and fever reliever during pregnancy. It was considered the safest option. But in 2025, the FDA issued a Notice to Physicians that changed everything. Based on studies of over 95,000 mother-child pairs, long-term use of acetaminophen during pregnancy was linked to a 28.6% higher risk of ADHD and a 20.4% higher risk of autism spectrum disorder.

That doesn’t mean you can never take it. It means you should use it only when necessary, at the lowest dose, and for the shortest time possible. A single dose for a headache? Probably fine. Taking it daily for two months for chronic back pain? That’s where the risk increases.

Here’s the catch: untreated fever is even more dangerous. A fever over 102°F during early pregnancy can raise the risk of neural tube defects by more than eight times. So if you have a high fever, don’t wait-take acetaminophen. But if you’re just feeling a little achy or have a low-grade temperature, try rest, hydration, and cooling methods first.

ACOG still lists acetaminophen as the preferred option, but the CDC now says pregnant women should “consider avoiding” it as a precaution. This isn’t a contradiction-it’s a shift toward caution. The science isn’t final. The ABC Study, tracking 50,000 pregnant women across 15 countries, is still ongoing. Results won’t be out until late 2025. Until then, use acetaminophen wisely, not routinely.

Safe Alternatives for Common Pregnancy Complaints

You don’t have to suffer. There are safe, effective options for the most common discomforts.

Pain and Fever

Stick with acetaminophen (325-650 mg every 4-6 hours, max 3,000 mg per day). Avoid NSAIDs after 20 weeks. For mild pain, try heat packs, massage, or prenatal yoga.

Allergies and Runny Nose

Second-generation antihistamines are your best bet:

• Loratadine (Claritin) - 10 mg daily
• Cetirizine (Zyrtec) - 10 mg daily
• Fexofenadine (Allegra) - 180 mg daily

These have been studied in over 2,000 pregnancies through the MotherToBaby registry with no increase in birth defects. Avoid first-gen antihistamines like diphenhydramine (Benadryl) for long-term use-they can cause drowsiness and may affect fetal movement.

Nasal Congestion

Start with saline nasal sprays and steam inhalation. If you need more, pseudoephedrine (Sudafed) is okay after the first trimester, but only at 30-60 mg every 4-6 hours, no more than 120 mg a day. Don’t use it if you have high blood pressure-it can raise it by 5-10 mmHg.

Constipation

Diet and water are first-line: aim for 25-30 grams of fiber daily and drink at least 8-10 glasses of water. If that’s not enough, docusate sodium (Colace) at 100 mg twice daily is safe and effective. If you still need help, polyethylene glycol (Miralax) at 17g daily is also Category B and has been used safely in over 700 pregnancies.

Depression and Anxiety

Untreated depression during pregnancy increases the risk of preterm birth by 64% and low birth weight by 73%. Stopping antidepressants can trigger relapse in 20-25% of women. The risk of birth defects with most SSRIs is small, but paroxetine (Paxil) has a slightly higher risk of heart defects (1.5-2% vs. 0.7% baseline). Sertraline (Zoloft) and citalopram (Celexa) are often preferred. Talk to your doctor about therapy, support groups, and medication together.

When to See Your Doctor Before Taking Anything

Don’t guess. Even if it’s “just” a cold medicine or a herbal supplement, check with your provider. Here’s when to call:

• You’re taking a medication for a chronic condition (epilepsy, diabetes, depression, high blood pressure).
• You’ve already taken a medication you now know is risky-don’t panic, but do call your OB.
• You’re considering a new supplement, herb, or over-the-counter product.
• You’re planning to get pregnant and are on any regular medication.

Preconception counseling isn’t just for high-risk pregnancies. It’s for anyone who takes medication. Switching from valproate to lamotrigine before pregnancy, or changing from warfarin to heparin, takes time. Don’t wait until you’re pregnant to figure it out.

What to Do Right Now

You don’t need to overhaul your life overnight. Start with these steps:

1. Make a list of every medication, supplement, and OTC product you take-including vitamins, CBD, and herbal teas.
2. Check the FDA’s Pregnancy and Lactation Labeling Rule (PLLR) for each one. You can search by drug name on the FDA website.
3. Call MotherToBaby (1-866-626-6847) or visit MotherToBaby.org. They offer free, confidential advice from specialists who review pregnancy medication data daily.
4. Don’t stop prescribed meds without talking to your doctor-even if you think they’re risky.
5. Keep your list updated. Bring it to every appointment.

Many women who call MotherToBaby have already taken a risky medication. That’s okay. The goal isn’t perfection-it’s awareness. Most exposures don’t lead to problems. But knowing what to avoid helps you make smarter choices moving forward.

The Bigger Picture

The market for pregnancy-safe medications is growing-$1.2 billion globally in 2022. But behind that number are real women, scared to take anything, and scared not to. The science is evolving. What we thought was safe five years ago might not be today. That’s why you need to stay informed, not scared.

There’s no perfect pill. But there are safe choices. And there’s support. You’re not alone in this. Millions of women have walked this path before you. With the right information, you can protect your health and your baby’s too.