Giving kids with peanut allergies tiny doses of peanuts to build up their immunity might actually make things worse, a new study in the Lancet medical journal suggests. The researchers say they're not denouncing the approach, called oral immunotherapy, but are calling for better methods and further study. The new research looked at the results of a dozen controlled trials involving 1,000 people—mostly children, with an average age of 9, reports the CBC. Those who received microdoses of peanuts, compared to those who received placebos or nothing at all, were more likely to suffer some kind of reaction, per USA Today, ranging from mild (vomiting) to severe (an anaphylactic reaction requiring epinephrine). No deaths were reported, but the risk of reaction rose from 7.1% to 22.2%, reports CNN.
"The risk or the chance of having a reaction is much higher, two to three higher on [oral] immunotherapy," says Dr. Derek Chu of Canada's McMaster University. To make things a little more confusing for worried parents, CTV notes that a different study in children ages 1 to 5 (young than those in the newer study) suggests that oral immunotherapy is, in fact, a good approach. “The younger the better,” says a University of British researcher involved in that research. “If you have a 1-year-old, that would be ideal.” The upshot seems to be that parents and patients need to exercise caution with any of these emerging approaches, especially since factors such as exercise or even a hot shower too soon after consuming the microdose can have an effect. This therapy is still "experimental," says Chu. "Patients need to know the facts exactly where the field is at." (Read more peanut allergy stories.)