The established histopathologic attributes of FFD are nonspecific, and a retention vesicle is difficult to find even in level sections. In contrast, perifollicular foam cells are a distinct, relatively consistent, and specific feature of FFD. We contend that perifollicular foam cells represent a useful hallmark of FFD.

Extrapolation using national hospital admission data and the prevalence identified by pooling international studies should be carried out with great caution.

The costs of potentially preventable hospital admissions related to medication are considerable. Therefore, patient safety interventions to prevent ADEs and hospital admissions may be cost-effective or even cost saving.