Allergy to Humidity: Everything You Need to Know

Many patients develop allergic reactions from humidity. Let's see what is hidden behind these episodes.
Allergy to Humidity: Everything You Need to Know

Last update: 06 September, 2021

Informally, patients use the term allergy to humidity to describe reactions to certain atmospheric contexts. It isn’t generally used in medical literature, although it can be very helpful in grouping symptoms with a common manifestation. It’s associated with the coldest seasons (winter) or areas that have a high percentage of humidity or damp.

These conditions can also aggravate other conditions, such as asthma. Today we’ll tell you everything you need to know about it, including its triggers and what you can do to reduce the chances of a reaction.

Is it possible to have an allergy to humidity?

In reality, there’s no such thing as an allergy to humidity. Humidity, or damp, is nothing more than the amount of water vapor that’s concentrated in any given place and, by itself, it can’t trigger an allergic process. However, humidity does create the conditions for some allergy triggers to proliferate.

For example, high humidity concentrations contribute to the increase of fungi and mites. Apart from pollen, these are two of the main causes of allergies.

Allergy to fungi

As the American College of Allergy, Asthma & Immunology points out, mold is a potential trigger for allergic reactions. Mold is a type of fungus without a predefined shape, as it’s characterized by spots in different shades of gray in humid places. Mold can also be in the air.

The Centers for Disease Control and Prevention (CDC) note that mold can also trigger an asthma attack and worsen other lung conditions (such as COPD). This isn’t the only species that can cause complications.

Many species release spores that travel hundreds of miles through the air. When inhaled, allergy sufferers develop a reaction. Some studies indicate that up to 30% of allergic patients are sensitive to fungal spores; this is 6% of the general population.

Mold on the wall causes a moisture allergy.
Mold is one of the real culprits we can identify when there’s an allergy to damp.

Mite allergy

There’s evidence that mites reproduce and proliferate more in humid environments. Mites are a type of arachnid that lives in dust and on blankets, pillowcases, blankets, and sheets. According to researchers, the main source of allergy is its fecal granules, which can cause asthma, rhinoconjunctivitis, and atopic dermatitis.

You can’t see the mites with the naked eye, although if the humidity concentrations are high you can be sure that there’ll be thousands and thousands around you. This explains why many of the allergic episodes are worse at night. You generally spend more time sitting on the couch and in bed, two places where these arachnids live.

Even after they die, they continue to cause you problems, as their waste and corpses remain there to cause allergies. They proliferate in places where there’s between 70% and 80% humidity.

Asthma and allergy to humidity

So, in reality, an allergy to humidity is an allergy to mites or fungi. At this point you should bear in mind that high concentrations of water vapor can trigger asthma attacks, as indicated by the Asthma and Allergy Foundation of America. It can do it in three ways:

  1. Difficulty breathing: Most asthmatics agree that humid air is heavier when breathing. Given its predisposition to complications, the airways can act negatively to this stress.
  2. It’s associated with extreme temperatures: Humidity is accompanied by extreme cold or heat. The lungs of asthmatics don’t tolerate changes of this type very well, as this evidence points out.
  3. The air quality is lower: As we’ve already explained, humidity increases the amount of mold and mites in the place. It also does the same with ozone.

Moisture and skin reactions

An allergy to humidity can not only trigger asthma attacks or typical allergy symptoms. In certain contexts, some patients may develop skin complications:

  • Aquagenic cigar: This condition is characterized by an itch on the surface of the skin without visible manifestations in the form of rashes.
  • Cholinergic urticaria: This is a type of physical urticaria where you develop rashes due to exercise or any type of activity and context related to sweating.
  • Aquagenic urticaria: This is a rare manifestation of urticaria in which the patient develops visible reactions after contact with water.
Urticaria on the arm due to allergy to humidity.
Allergy to humidity also affects the skin and not just the lungs.

What can you do about it?

Since studies and research support the use of dehumidifiers to reduce mite concentrations, you should consider purchasing one if these arachnids are the trigger for your episodes. They’re also useful for fighting mold and spores.

Apart from this, put the following into practice:

  • Reduce the number of indoor plants in your home
  • Avoid drying clothes inside the home
  • Open the windows to prevent moisture from collecting
  • Use fans instead of air conditioners
  • Always use your kitchen utensils with a lid
  • Make sure you don’t have water leaks in the bathrooms

Other things you can do is keep your home dust-free with the help of a vacuum cleaner, change curtains and covers regularly, remove rugs, and attack mold concentrations as soon as you start to notice them. If you apply all this, your allergy episodes will be reduced.



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