4 ms·
“Everything you're allergic to is something you were exposed to at least once” If you’re saying first exposure is what triggers/causes the allergy, I don’t bel
by jzb 3y ago
“Everything you're allergic to is something you were exposed to at least once”
If you’re saying first exposure is what triggers/causes the allergy, I don’t believe this is true. Some people find out they’re allergic to penicillin the first time they get a dose. If they’re very unlucky it’s fatal.
- modeless 3y agoThe mold that produces penicillin is common indoors. It doesn't take a lot of exposure.
- projektfu 3y agoThat's a type II hypersensitivity (IgM or IgG antibodies starting the complement cascade) and it's different from type I allergies (IgE causing mast cell degranulation). Type IV (cell-meditated, lymphocyte reaction) hypersensitivity, like poison ivy, is also different. And then there's a whole bunch of other hypersensitivities that are poorly understood, like atopy.