# Developing allergies over time? **URL:** \ **Category:** Factual Questions\ **Created:** [July 15, 2002, 9:29am UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025 "2002-07-15T09:29:50Z")\ **Posts on this page:** 8\ **Page:** 2
**Author:** ![Racer1](https://avatars.discourse-cdn.com/v4/letter/r/ee59a6/32.png) [@Racer1](https://boards.straightdope.com/u/Racer1)\ **Post date:** [July 17, 2002, 7:47am UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/21 "2002-07-17T07:47:32Z")
Thanks for the concern and explanations, everyone. I’m pretty sure I’m okay. I called the nurse at my local doc’s (my doctor is on vacation) and explained the symptoms and background. She told me to go out and buy some special anti-allergy pills (which I have) and to call back if it gets any worse or if it hasn’t got any better in 48 hours. It seems like it’s a bit better already so I’m not too worried anymore. **Dmark** , well I was walking around the backyard barefoot when I got stung once, but I’m afraid I forgot the honey and being naked bit. 😃 This last time I was stung, the damn thing must have flown up my shirt while I was bent over trying to fix a desk. The first I knew about it was when I felt the pain. I haven’t really been stung _that_ much… seven times and I’m 23. We can probably chalk about 5 of those times up to when I had a wasp’s nest in the attic above my bedroom too. Ah, well… maybe I just have one of those faces you just wanna sting! 😃 ---
**Author:** ![Bob\_Scene](https://avatars.discourse-cdn.com/v4/letter/b/e19adc/32.png) [@Bob\_Scene](https://boards.straightdope.com/u/Bob_Scene)\ **Post date:** [September 27, 2002, 4:07am UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/22 "2002-09-27T04:07:21Z")
> [@](#): > > \*Originally posted by Smeghead \* > \*\*What **choosybeggar** said. “Allergies” covers all four types of hypersensitivity reactions. Type 4 is just the type that requires previous exposure. \*\* According to my textbooks and recent medical school lectures I’ve attended, you are completely wrong from start to finish, even though you claim to have a book on the subject. You can smugly insist otherwise, but that doesn’t make you right. You are completely misunderstanding the phrase “delayed-type hypersensitivity,” even after I corrected you on it. Once again, a delayed hypersensitivity reaction, or type IV, is **not** “just the type that requires previous exposure,” and it is **not,** despite what you said, the one involved in bee-sting allergies. > [@](#): > > Type I hypersensitivity (anaphylactic type) may be defined as a rapidly developing immunologic reaction occurring within minutes after the combination of an antigen with antibody bound to mast cells or basophils in individuals previously sensitized to the antigen. > [@](#): > > Type IV hypersensitivity (cell mediated)… is initiated by specifically sensitized T lymphocytes. It includes the classic delayed-type hypersensitivity reactions initiated by CD4 T cells… In a previously sensitized individual, reddening and induration of the site appear in 8 to 12 hours, reach a peak in 24 to 72 hours, and thereafter slowly subside. The above quotes are from _Robbins Pathological Basis of Disease,_ one of many cites I can provide ([and here’s one web-based one that took about two seconds to find with Google](http://www.outlinemed.com/demo/allergy/4850.htm)). Do those make it clear enough to you the difference between immediate and delayed-type hypersensitivity? As for your claim that “allergies” covers all four types of hypersensitivity reactions, let’s see you prove it. Come up with some cites where people who treat the conditions in question refer to erythroblastosis fetalis or pernicious anemia (type II hypersensitivity reactions) as “allergies.” Show me a cite where a specialist refers to SLE or acute glomerulonephritis (type III hypersensitivity reactions) as “allergies.” Show me a cite where someone refers to transplant rejection, a positive PPD test, or any type IV hypersensitivity reaction other than contact dermatitis as “an allergy.” Either **prove** you’re right (claiming to have a book on the subject and refusing to quote from it, or just saying I’m wrong without elaboration doesn’t constitute “proof,” by the way) or quit saying I’m wrong. ---
**Author:** ![happyheathen](https://avatars.discourse-cdn.com/v4/letter/h/b5e925/32.png) [@happyheathen](https://boards.straightdope.com/u/happyheathen)\ **Post date:** [September 27, 2002, 5:01am UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/23 "2002-09-27T05:01:11Z")
**Racer** - If _I_ had that kind of reaction after 7 exposures, I would want some really massive meds _on my person_ when #8 comes around. See a specialist, 'K? ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [September 27, 2002, 4:40pm UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/24 "2002-09-27T16:40:28Z")
So, in a nutshell, am I correct in saying that all true allergic reactions (type 1 hypersensitivity, such as a beesting) require previous exposure, as well as type 4 hypersensitivity (which is not called an allergic reaction)? ---
**Author:** ![etv78](https://avatars.discourse-cdn.com/v4/letter/e/d78d45/32.png) [@etv78](https://boards.straightdope.com/u/etv78)\ **Post date:** [September 27, 2002, 5:32pm UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/25 "2002-09-27T17:32:45Z")
I am SEVERLY (anaphallitically) allergic to latex. (I touch it, don’t do anything to combat it, I DIE!) I have been operated on innumberable times, and, at one time, used latex catheters to urinate. Thus significant latex exposure. During one of these hospitalizations, I was cathing, using latex gloves. Well, my airway closed off, and my hand swelled up. The allergy test was the worst they had ever seen. Had I been home, and had this reaction, I likely would’ve died. ---
**Author:** ![Bob\_Scene](https://avatars.discourse-cdn.com/v4/letter/b/e19adc/32.png) [@Bob\_Scene](https://boards.straightdope.com/u/Bob_Scene)\ **Post date:** [September 27, 2002, 5:59pm UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/26 "2002-09-27T17:59:57Z")
> [@](#): > > So, in a nutshell, am I correct in saying that all true allergic reactions (type 1 hypersensitivity, such as a beesting) require previous exposure, as well as type 4 hypersensitivity (which is not called an allergic reaction)? Yes, except that some people do refer to contact dermatitis as an allergy (nickel allergy, for example), even though it’s type IV. ---
**Author:** ![Magickly\_Delicious](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magickly\_Delicious](https://boards.straightdope.com/u/Magickly_Delicious)\ **Post date:** [September 27, 2002, 10:35pm UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/27 "2002-09-27T22:35:12Z")
Okay, so I have something similar–I developed sudden nasal allergies about 2 years ago. Now every summer I get bad allergies that no meds seem to help. So is there a chance that this will go away as suddenly as it showed up? I _think_ it’s pollen I’m allergic to, because it starts in April and doesn’t end until mid-August. Could it be stress-induced? ---
**Author:** ![artemis](https://avatars.discourse-cdn.com/v4/letter/a/91b2a8/32.png) [@artemis](https://boards.straightdope.com/u/artemis)\ **Post date:** [September 28, 2002, 3:00am UTC](https://boards.straightdope.com/t/developing-allergies-over-time/119025/28 "2002-09-28T03:00:23Z")
> [@](#): > > \*Originally posted by choosybeggar \* > \*\* > > BTW, there is (at least?!?) one exception to the "you need exposure to become allergic " rule. This allergen in question is common and MD’s and lab technicians work diligently to ensure that these serious allergic reactions don’t occur. This allergen is ABO mismatched human donor blood. If you have blood type “O” then you possess **preformed** antibodies to the “A” and “B” blood antigens ( If you are “A” then you have preformed anti-“B” antibody. If you are “B”, then you have preformed anti-“A”). If a type “O” individual were transfused with “A”, “B”, or “AB” blood, the preformed antibodies in their circulation would lyse the donor blood cells, causing many uncomfortable sensations and possibly death. This is a type II (antibody-mediated cytotoxicity) response and I’d argue falls within the definition of allergy. \*\* Actually, there IS a previous exposure involved in the case of ABO mismatch reactions. As it turns out, the A and B blood group antigens share a similar structure with certain polysaccharides found on some bacterial cell walls. The body may never have seen “foreign” blood before, but it definitely has seen those bacteria (which are ubiquitous), and has made antibodies to the foreign polysaccharides, antibodies which also recognise the A and/or B blood group antigens. Hence the transfusion reaction following an ABO mismatched transfusion, even in a patient without a prior history of blood exposure. [Previous page](https://boards.straightdope.com/t/developing-allergies-over-time/119025.md?page=1)