Does rain make allergies worse?

Does rain make allergies worse? Many people frequently report worse allergy symptoms in the rain. Treatments follow most of the standard guidelines for allergies, but you may also want to use a dehumidifier.

A child with a colorful umbrella playing in the rain.
Catherine Falls Commercial/Getty Images

Some people experience worse allergy symptoms on rainy days. This can happen when the damp weather encourages the growth of allergens such as mold and dust mites. It can also happen when rain breaks up pollen into smaller particles and causes it to scatter further.

Allergy medications and steps such as running a dehumidifier can help treat rainy day allergies.

Why are my allergies worse when it rains?

Rain can make some allergies worse. This can include allergies to certain pollens, mold, dust, and grass. When rain falls on these allergens, it can break them up into smaller bits. This leads to easier spreading and can result in worse allergies.

Additionally, allergens such as dust mites and mold grow in damp conditions. Rainy weather can increase the number of these allergens, both indoors and outdoors. This can lead to increased allergy symptoms.

Rain also leads to many people spending the day inside. For people with indoor allergies, such as allergies to mold, dust, and pet dander, this can mean more time surrounded by those allergens. This can worsen symptoms, especially if rain leads to an increase in the amount of dust or mold in a space.

Can rainwater cause allergic reactions?

Rainwater can contain toxins and pollutants. The Centers for Disease Control and Prevention (CDC) state that rainwater might contain dust, smoke, asbestos, lead, copper, and other chemicals. Additionally, rainwater may contain viruses, bacteria, parasites, and mold.

Rainwater can cause allergic reactions and even serious illness. Rainwater isn’t considered safe for household use unless it’s been treated and tested. The CDC recommends that people with weakened immune systems exercise additional caution before using rainwater.

What allergies flare up when it rains?

Certain allergies are more likely to flare up when it rains. This can include:

  • Pollen: Rain prevents pollen from traveling and can be a relief for some people with this common allergy. However, it can also increase pollen exposure when pollen is broken into smaller particles. Pollen counts also sometimes increase significantly right after rainstorms.
  • Dust: Dust mites thrive in humidity and warmth. Rain can increase dust mite numbers and can make symptoms worsen.
  • Mold: Similar to dust, mold grows when it has moisture and warmth. Rain can increase mold both indoors and outdoors.
  • Grass: Heavy rain breaks up grass pollen. This can lead to more free-floating grass pollen in the air, and that can lead to worsened allergy symptoms.

Rainy day allergy symptoms

The symptoms of allergies on a rainy day can vary depending on the specific allergy and the person.

Some people might experience a reduction in symptoms when the rain first starts but then see symptoms spike later in the day. This can happen when the broken-up pollen disperses in the air.

It’s common for allergies to include:

  • congestion
  • sneezing
  • runny nose
  • wheezing
  • dry cough
  • shortness of breath
  • fatigue
  • itchy eyes
  • red eyes
  • watery eyes
  • swollen eyes
  • mal de tête
  • vomissement
  • hives and other rashes
  • irritability

Treating rainy day allergies 

Here are some steps you can take to help reduce the symptoms of rainy day allergies:

  • Keep windows shut during rainy weather, especially in allergy season.
  • Monitor the pollen count and mold count in your area.
  • Take allergy medications, such as antihistamines, on rainy days.
  • Use saline nasal sprays for symptom relief.
  • Try nasal corticosteroid sprays to manage allergy symptoms.
  • Use a dehumidifier to remove excess moisture from the home.
  • Clean your home regularly to avoid the buildup of dust.
  • Check for any leaks in your roof regularly to prevent excess water that can encourage mold and dust growth.

If your rainy day allergies are severe and over-the-counter treatments don’t seem to help, you may want to make a medical appointment.

A doctor can recommend or prescribe additional options. For instance, prescription immunotherapy injections help some people with seasonal allergies find relief.


Rainy days can be allergy days for people with pollen, grass, dust, and mold allergies. This happens when rain causes pollen to break into smaller pieces and spread through the air, or when rainy weather increases the growth of mold and dust mites.

People who experience allergy symptoms on rainy days may find relief by closing windows, running dehumidifiers, and taking allergy medications.

5 commentaires

  1. Rain can indeed have mixed effects on allergies. On one hand, rain can wash away pollen from the air, providing temporary relief to allergy sufferers. On the other hand, rain can promote the growth of mold and increase humidity, which can exacerbate mold allergies. Additionally, when the rain stops, plants and trees may release more pollen, leading to higher pollen counts. So, while it might feel better during the rain, there could be a flare-up once it subsides. It’s always a good idea to keep an eye on local pollen counts and take precautions accordingly.

  2. Absolutely, rain can indeed impact allergies. While rain often helps wash away airborne allergens like pollen, it can also cause plants to release more pollen once the rain stops. Additionally, mold spores tend to thrive in wet environments, which can exacerbate allergy symptoms for those sensitive to mold. So it really depends on the type of allergen one is reacting to and the specific weather conditions following the rain.

  3. Sure! Rain can actually have a mix of effects on allergies. Initially, rain can help wash pollen out of the air, providing some temporary relief for allergy sufferers. However, after the rain stops, the increase in moisture can lead to a higher growth of mold and more pollen being released from plants. So, while you might feel better during and immediately after the rain, your symptoms could flare up again once everything dries out. It’s always a good idea to monitor the weather and take preventive measures to manage your allergies effectively!

  4. Absolutely, rain can both alleviate and exacerbate allergies, depending on the specific allergens you’re dealing with. Rain can wash away pollen and reduce its concentration in the air, providing relief for those allergic to pollen. However, it can also increase mold growth and release spores, which can worsen symptoms for mold allergy sufferers. Overall, the effect of rain on allergies can vary greatly from person to person.

  5. This is a great topic! Rain can actually have both positive and negative effects on allergies. On one hand, rain can help wash away pollen from the air, providing temporary relief for those with pollen allergies. On the other hand, rain can also make the ground damp, which promotes the growth of mold and can stir up spores that exacerbate mold allergies. Additionally, after a heavy rain, plants may release more pollen, leading to a spike in pollen counts once the rain stops. It really depends on the specific allergens you’re sensitive to. Thanks for sharing this post!

Laisser un commentaire

Votre adresse e-mail ne sera pas publiée. Les champs obligatoires sont indiqués avec *