How do we deal with people sensitive to antibiotics (beta lactams)?

We should ask pxs if they have any allergies to medications, if they say that they are allergic to penicillin for example, they may be also allergic to other beta lactams. So we ask them about the type of allergy, is it a rash or anaphylaxis, if its a rash, we can use other beta lactams, if anaphylaxis, we should not use beta lactams at all