On Tue, 02 Aug 2005 14:53:59 +0100, Peter Parry
wrote:

Aspirin, however, is not a protein, and people speak of being allergic
to aspirin.

Indeed, but it does not make it true. I know someone who claims to
be highly allergic to Asprin yet will eat Camembert Cheese by the
pound. In particular most sensitivities do not involve an allergic
reaction and specifically anaphylactic reaction.

The difference can be quite important, I once had to stop a well
meaning lady trying to inject an Epipen she carried for her own
peanut allergy into a young girl having a hysterical fit because she
had caught a whiff of floor polish which she was "allergic to" that
week.

I'm not sure you're right on this...but then again I'm not sure I'm
right either :-)

It would appear that hypersensitivity to penicillin is a type 1
hypersensitivity mediated by IgE. Penicillin is certainly not a
protein as the structure is far too simple:
http://en.wikipedia.org/wiki/Penicillin
(Look at the picture)

This article discusses allergic responses to penicillin and states
that the response is mediated by IgE and can cause anaphylaxis:

http://www.clevelandclinicmeded.com/...enallergy1.htm

Mr F