Allergies During Pregnancy: Symptoms and Safer Relief

What you need to know

• Allergy symptoms during pregnancy are unpredictable — they can improve, worsen, or stay the same, and can change again from trimester to trimester.
• Pregnancy rhinitis is nasal congestion caused by pregnancy hormones and increased blood flow, not by allergens, and it typically doesn't respond to antihistamines.
• No allergy medicine can be responsibly labeled simply “safe” or “unsafe” for pregnancy on a general health page; that depends on your trimester, symptoms, and health history, decided with your OB provider or pharmacist.
• If you also have allergic asthma, staying well controlled matters — undertreating asthma is not automatically the safer choice.
• Non-medication measures such as saline rinses and trigger avoidance carry no medication-related pregnancy risk and are reasonable to try first.
• Signs of a severe allergic reaction (anaphylaxis) during pregnancy are a medical emergency; call 911 immediately.

Why Allergy Symptoms Change During Pregnancy

Pregnancy hormones and increased blood volume change blood flow to the mucous membranes lining your nose, and immune function shifts in ways that aren't fully predictable from one pregnancy to the next. Some people find their usual seasonal or environmental allergy symptoms improve during pregnancy, some find they get worse, and others notice little change at all. There's no reliable way to know in advance which pattern you'll have, which is one reason tracking your symptoms and mentioning changes at prenatal visits is useful.

Pregnancy Rhinitis vs. Allergic Rhinitis

Because pregnancy itself can cause nasal congestion, it helps to know the difference between that and true allergies.

If you're not sure whether your congestion is allergy-related, pregnancy-related, or something else like a sinus infection, that's a good question for your OB provider rather than a guess.

If You Need Medication

This page intentionally does not sort allergy medications into “safe” or “unsafe” categories. Evidence on medication use during pregnancy is more limited than for the general population, so the right choice depends on your trimester, symptom severity, and health history. For that conversation, and a closer look at how clinicians and organizations such as ACOG approach it, see our allergy medicine during pregnancy guide, and bring specific product questions — including over-the-counter options — to your OB provider or pharmacist before starting, continuing, or stopping anything.

Non-Medication Steps You Can Try

• Saline nasal rinses or sprays to help clear congestion without medication
• Keep windows closed on high-pollen days and rely on air conditioning or filtered indoor air
• Use a HEPA air filter and vacuum and dust regularly to reduce indoor allergens
• Shower and change clothes after spending time outdoors during allergy season
• Elevate your head while sleeping if congestion feels worse lying flat
• If you're already receiving allergy shots (immunotherapy), ask your allergist about continuing during pregnancy; it's generally not started new during pregnancy, but an established, stable-dose course is often continued

If You Also Have Allergic Asthma

Allergic asthma can improve, worsen, or stay the same during pregnancy, and it can change again from one trimester to the next, so ongoing monitoring matters even if you've felt stable. It's worth being direct about something people sometimes get backward: cutting back on asthma treatment on your own to "play it safe" is not automatically the safer path, since poorly controlled asthma is itself a real risk during pregnancy. See our allergic asthma management guide for more on long-term control.

When to seek care

Practical next steps

Safe general steps

1. Track which symptoms you're having and when, to share at prenatal visits
2. Try non-medication measures first if symptoms are mild
3. Bring any medication questions, including OTC products, to your OB provider or pharmacist before use
4. Mention any allergic asthma so your control plan can be reviewed alongside your pregnancy care

Actions that need medical guidance

• Starting, continuing, or stopping any allergy medication during pregnancy
• Adjusting allergic asthma controller medicine during pregnancy
• Deciding whether to continue allergy shots (immunotherapy) during pregnancy

Frequently asked questions

Sources

1. ACOG — What medicine can I take for allergies while I'm pregnant?
2. PMC (NIH) — Rhinitis and pregnancy: literature review
3. PMC (NIH) — Asthma and Allergic Diseases in Pregnancy: A Review
4. PMC (NIH) — Allergen immunotherapy in pregnancy

Medical disclaimer: This guide is for general education and isn't a substitute for personalized medical advice. It doesn't provide dosing. Always talk to a qualified healthcare professional about your symptoms and treatment.

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