In my practice I try to apply some common sense, adopting a colleagues’ phrase “common things are common”.
This is particularly useful in the diagnosis of new problems that have eluded diagnosis, and I apply a lesson learned from a fellow resident (a PharmD before med school) who told me: new problems, ask about new meds.
So, if my patient has some new problem as part of the history (when did this start) I’ll follow up with ‘any new medications, or change in your meds, around then? (This is often fruitless despite the time investment to go through the meds, the list, then ‘when did that medication start’ conversations, but it’s time well spent).
Many times the reason the patient gets dizzy on standing is the new BP medication, or a BP med that has dehydration as a mechanism stacked onto decreased oral intake…
I’ve made a couple of good diagnoses recently, and it was directly because of questioning the timing of the new meds and the new symptoms, one patient with their second trip to the ED for an unexplained metabolic acidosis (who was taking a seizure med that said ‘metabolic acidosis’ as a known problem with it), so making the call to the pt’s doc for a re-admission and oh-by-the-way I believe the problem is this med that causes this problem. Nice way to have an admitting doc think you know what you’re doing…
Metformin causing diarrhea is a med-school diagnosis, so why it took the med student following me to make it I don’t know, but the patient and family were thrilled to have a reason for their debilitating symptoms. (Thanks, unnamed MS4!)
There are some others, but you get the message: temporally relating new meds then new symptoms, common things are common, and always question the medications.