Emilio Alvarez-Cuesta and fellow researchers at Hospital Ramon y Cajal  (named after Santiago Ramon y Cajal (1852-1934), a Spanish physician, histologist, and Nobel laureate) in Madrid, Spain, have been working at an immunotherapy treatment so people allergic to cats can still live with cats.

Their research has found that starting with very weak doses and then progressively giving stronger doses of cat dander extract under the tongue of patients--so that it is absorbed into the body--provides protection for children allergic to cats. 

In other words, the person’s immune system begins to recognize the cat dander, what causes the allergic reaction, and begins to work within the body to accept it, rather than reject it (cause an allergic reaction in the patient).

The act of placing an allergen under the tongue, in the form of allergy drops, is called sublingual immunotherapy (SLIT).

The results of the Alvarez-Cuesta team was wriiten up in the medical journal Allergy. Within their article, they explain how they divided up fifty children, one group was given the SLIT therapy once each day, while the other group was given a placebo, a passive dose without the allergen medicine. Over a one-year period, the subjects were observed as to their reactions to either the SLIT dose or the placebo dose. Periodically, they were put into a living area with cats for 1.5 hours at a time, with their reactions to the cats noted in their research.

Sixty-two percent of the children under the SLIT doses experienced reduced symptoms, while the control group experienced no difference in symptoms within the test. In addition, no major side effects were found in the group taking the dat dander extract.

The researchers feel their results provide a good possibility for eliminating or at least reducing allergies to cats in people who suffer such allergies.