One circulation time may be roughly considered to be on the order of a minute. The drug base itself produces little direct toxicity and is remarkably safe. However, biological and allergic reactions are possible. The biological reactions are similar to those discussed in the introduction to antimicrobials. They will be more marked with the broader spectrum derivatives that are absorbed less well from the intestine, e.g., ampicillin.
Hypersensitivity is the major problem associated with the penicillins.
The following percentages are approximations. Anaphylactic shock associated with penicillin therapy kills 300 patients per year. Cross sensitivity among the beta-lactam antibiotics is very likely. Study Questions 1. Think about maximum achievable plasma concentrations and reasons for needing to vary absorption rates.