Do cats cause asthma?

I was speaking with some friends and my wife last night and they all indicated that if you have cats in the house with infants it can cause them develope asthma. All 3 of them said yes this is well know in their country of origin (Costa Rica, Mexico, and Thailand). I had never heard of it.

This sounded fishy to me, I did some checking around on the net and found some papers on medical sites dated in the 1990’s that there are links. I saw another on dated from 2000 that there was no link to it creating the asthma but if the infant already has asthma it will cause problems.
What is the SD?

Thank you

Lots of people are allergic to cats, and an alergic reaction often includes asthma. Also, allergies change over time, and it is common for a childhood allergy to disapear in adulthood and vice-versa.

However, I don’t know of any causal relation between the presence of cats and developing asthma.

I’ve read it’s actually better to be exposed to antigens (like cat dander and dust) at an earlier age, for some reason these people develop less allergies later in life.

If you are allergic to cat dander it can trigger an asthma attack.

There is no evidence that exposure to cat dander causes asthma.

There is also no evidence that exposure to cat dander prevents asthma.


I had cats (I love them) for years before I started getting asthma attacks. I can’t tell you how many times I was taken to the emergency room for it. Finally I went to the doctor, who did an allergy test and determined it was from cat dander. Had to get rid of the cats and hadn’t had an asthma attack since. To this day if I touch a cat (which is hard not to do since I love them so much), my eyes get watery and bloodshot, my skin itches like mad and I start sneezing (apparently sleeping in a house with cats triggers the asthma). So I definately developed an allergy to cats!

Actually, there’s some recent research suggesting that this actually is the case … I’d suggest revising this to ‘very little evidence’. :slight_smile:

Here’s an example … try Googling on ‘asthma hygiene hypothesis’ for some others.

Still hypothetical, but there seems to be enough statistical evidence turning up to drive more studies. Either that, or enough grant money to drive them …

From your link, SCSimmons.

I knew I should have hung more caveats on my statement. The evidence is not anywhere near conclusive as to whether cat dander causes, prevents, or does nothing for engendering the disease of asthma. Fascinating hypothetical models are proposed for all 3 effects. They can’t all be true. More research is needed.

The hygiene hypothesis is fascinating, but focuses mainly on the role of infectious agents. Studies are contradictory in their results. I look forward to seeing more data on allergenic roles and further work on eosinophilic apoptosis.

Thanks for the link, SCS