Allergy Medications During Pregnancy: What’s Safe and What to Avoid

Managing allergies during pregnancy isn’t just about sneezing or itchy eyes-it’s about making choices that protect both you and your baby. Around 20-30% of pregnant people deal with allergic rhinitis, hives, or conjunctivitis, and many need medication to function normally. But not all allergy drugs are created equal when you’re expecting. Some are safe. Others carry risks you can’t afford to ignore.

First Trimester: The Most Sensitive Time

The first 12 weeks of pregnancy are when your baby’s organs are forming. That’s why doctors recommend avoiding all non-essential medications during this time-even if you think they’re harmless. If your allergies are mild, start with non-drug options: rinse your nose with saline spray or a neti pot, use a HEPA air filter, keep windows closed during high pollen seasons, and wash your bedding weekly in hot water. These steps reduce exposure without any drug risk.

If symptoms are severe enough to disrupt sleep or daily life, talk to your provider. Some medications are still considered low-risk even in the first trimester. Nasal corticosteroids like Rhinocort (budesonide) and Flonase Allergy Relief (fluticasone propionate) have been studied in over 200,000 pregnancies and show no increased risk of birth defects. Rhinocort is often preferred because it’s the most thoroughly studied nasal steroid in pregnancy.

Oral Antihistamines: First-Gen vs. Second-Gen

Antihistamines are the most common oral treatment for allergies. But not all are equal when you’re pregnant.

First-generation antihistamines like diphenhydramine (Benadryl) and chlorpheniramine (Chlor-Trimeton) have been used for decades. Studies tracking hundreds of thousands of pregnancies found no link to birth defects. They’re effective, but they cause drowsiness-sometimes so much that driving or working becomes unsafe. Many pregnant people still use them because they’re cheap, available over the counter, and well-documented.

Second-generation antihistamines like cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra) are non-sedating and preferred by many for daytime use. Cetirizine and loratadine have strong safety data from multiple large studies. Fexofenadine is trickier: it’s labeled Pregnancy Category C by the FDA, meaning animal studies showed possible risks, but human data is limited. Still, no clear danger has been found in human pregnancies. Most doctors feel comfortable prescribing it after the first trimester.

Important: Avoid combination products. If you see a product labeled Claritin-D, Zyrtec-D, or Allegra-D, don’t take it. The “D” means it contains pseudoephedrine-a decongestant that’s risky in early pregnancy.

Decongestants: The High-Risk Category

Pseudoephedrine (Sudafed) is the most common oral decongestant. It’s effective for stuffy noses-but dangerous in the first trimester. A 2009 study found that taking pseudoephedrine between weeks 3 and 8 of pregnancy was linked to a 2.4 times higher risk of gastroschisis, a serious abdominal wall defect. Because of this, most experts advise avoiding it entirely during the first 12 weeks.

After the first trimester, some providers may allow limited use: no more than 30-60 mg every 4-6 hours, not exceeding 240 mg in 24 hours. But even then, it’s not first-line. Pseudoephedrine can raise blood pressure, which is risky if you’re already prone to pregnancy-induced hypertension.

Phenylephrine, another decongestant found in many cold meds, has even less safety data. It’s also Pregnancy Category C. Avoid it unless absolutely necessary.

Nasal spray decongestants like Afrin (oxymetazoline) are sometimes used for short-term relief-no more than 3 days. But they’re not recommended for routine use. They can cause rebound congestion and have not been studied well in pregnancy. The American College of Allergy, Asthma, and Immunology says there’s not enough evidence to call them safe.

What About Nasal Sprays?

Nasal corticosteroids are the gold standard for allergic rhinitis during pregnancy. They work locally in the nose, so very little enters your bloodstream-and even less reaches the baby.

Safe options include:

• Rhinocort (budesonide) - most studied, preferred choice
• Flonase Sensimist (fluticasone furoate)
• Nasonex (mometasone)
• Flonase Allergy Relief (fluticasone propionate)

One spray to avoid: Nasacort (triamcinolone). GoodRx’s 2023 review flagged it as contraindicated in pregnancy due to insufficient safety data. Even though it’s similar to other steroids, there’s not enough evidence to say it’s safe.

Immunotherapy and Asthma Medications

If you were already getting allergy shots before pregnancy, you can usually continue them. The American College of Allergy, Asthma, and Immunology says stopping them could cause worse symptoms-and that’s riskier than continuing. But never start allergy shots while pregnant. Your immune system is already changing, and introducing new allergens could trigger unpredictable reactions.

For asthma, which affects about 8% of pregnant people, inhaled corticosteroids like budesonide or fluticasone are safe and recommended. Oral steroids (like prednisone) should only be used if absolutely necessary, and then only under close supervision. Uncontrolled asthma poses a greater risk to the baby than most asthma medications.

Dosing and Formulations to Watch For

Even safe medications can become risky if misused.

• Use the lowest effective dose. For cetirizine, that’s 10 mg once daily. For loratadine, also 10 mg daily.
• Avoid extended-release (ER) or sustained-release (SA) versions. These release medication slowly, increasing exposure.
• Stay away from multi-symptom cold and allergy pills. They often combine antihistamines with decongestants or pain relievers you shouldn’t take.
• Don’t assume “natural” or “herbal” remedies are safe. Many lack testing in pregnancy and can interfere with hormones or blood flow.

What’s Changing in 2025?

The FDA stopped using the old A, B, C, D, X pregnancy risk categories in 2018. Now, labels include detailed narratives about risks, benefits, and data sources. But many doctors and websites still refer to the old system-so you might see conflicting info. Always ask: “Is this based on human data or just animal studies?”

A major shift is coming. The NIH’s Pregnancy Exposure Registry, which has tracked over 15,000 pregnant women taking allergy meds since 2018, is expected to release preliminary results in late 2024. These findings will likely shape the next round of guidelines in 2025.

When to Call Your Doctor

You don’t need to suffer through allergies-but you also shouldn’t guess about meds. Call your provider if:

• Your symptoms are worse than usual or not improving with safe options
• You’re considering any new medication, even if it’s “over the counter”
• You’ve taken a medication you’re unsure about, especially in the first trimester
• You have asthma or high blood pressure along with allergies

Your doctor can help you choose the safest, most effective option for your specific situation. Don’t wait until symptoms are unbearable. A quick call now can prevent bigger problems later.