Prescription error – part 2

Clinical Pharmacology and Toxicology

Continued from previous question.

A further history is taken from Mr Pan about his “penicillin allergy”.

He tells you he has taken penicillin on 3 occasions and completed the course. However he tells you.

On the first occasion after 3 days he vomited and he think the drug made him feel sick (but completed the course).

On the second occasion it was for an infection and he had a rash on his feet but no other ill effects (completed the course).

On the third occasion he had diarrhoea. (Stopped the course after 4 days).

He tells you he spoke to a friend who was a medical student and was told he must be allergic to penicillin. You check his notes and confirm he has received the prescriptions.

Should he be recorded as having a penicillin allergy for the purposes of his notes?

  • Yes but he can probably take penicillin in the future
  • Yes and he should not be given furhter penicillin or its derivatives
  • Not allergic: if needed can safely be prescribed penicillin in the future
  • Not allergic : however should not be prescribed penicillin in the future
  • Should not take penicillin again but can take amoxycillin


Adverse drug reactions are common and side effects are common. Each of these symptoms could be considered a side effect but this doesn’t mena that the drug is contraindicated.

There may be a time in the future where withholding penicillin inappropriately could harm the patient.