Haptens - What happens to the body when an allergy to something like penicillin occurs?

I read somewhere that haptens become attached to carrier molecules..Can someone explain this concept to me a little better. My mom is on peniclllin for a week and she has been vomiting all day today and i wonder if she is having a reaction.
Answer:
The immune system is tuned to be able to tell the difference between self molecules and foreign molecules. This is how it combats infections and such. In autoimmune disorders, this system is messed up and actually begins attacking self cells. The immune system usually recognizes larger molecules (peptides, etc), however in the case of haptens, when a small molecule (e.g. penicillin) is bound to some other protein in the body, it can be recognized as foreign and cause an immune reaction (e.g. "allergies"). These would generally occur more quickly than a week and would usually present with breathing trouble and hives, however, it's always ok to call the doctor and ask them if she needs to come back in. Also, check the bottle and see if the meds should be taken with food. sometimes a piece of toast and a glass of water is all that is needed to help with this.Take home lesson ;) : never hesitate to call the doctor's office and ask if something doesn't seem right. it's their job! :)

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It may be allergic reaction , she might have an allergy test to decide, but tell me if she developed any other symptoms rather than vomiting?!
but take into ur consideration that some penicillin's as ampicillin cause GIT upset , this may an obvious reason for vomiting!! especially if she ingested them on empty stomach

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Allergy Requires IgE, Much that What is Said Above is True. See Type I Hypersensitivity.

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