immuno definitions

there are some words you need to become familiar with.
Antigen is foreign to the body, and when introduced into the body, stimulates the production of specific antibodies
Antibodies are produced by the body in response to antigens and are specific to the antigen
Pathogen is a micro organism capable of causing disease in man.
Immunogenic means capable of stimulating an immune response
Non immunogenic obviously means incapable of stimulating an immune response
Specific immune response (SIR) is the immune response developed by us in response to the antigens we are exposed to. Yours is different to mine. His is different to hers.
Non specific immune response (NSIR) is the immune response we are all born with. Everybody's is the same. It includes examples like tears, intact skin, immune cells, etc

Only complete antigens are immunogenic. Incomplete antigens need to be coupled with a carrier protein before it can become immunogenic. A hapten is an incomplete antigen, therefore it is non immunogenic. Examples of haptens are drugs like analgesics, and antibiotics. I think it is a good idea that we don't develop immune reactions to medication, don't you? Imagine if you produced antibodies to medication???? That would be horrific.
So first question:what is an analgesic? a good example please trade names acceptable

some acceptable abbreviations
Antigen = Ag
antibody = Ab
immune response = IR
SIR and NSIR from above

so I have a situation that needs explaining. Comments please after reading
you have probably heard about penicillin allergies? These patients could have a fatal reaction to penicillin. So if penicillin is an antibiotic, and antibiotics are haptens, how is it possible that people can be allergic to it?

that's all for now.