The example given for the current limitation for defining a maximum dose per course also includes an instruction for a period of time where medication should not be taken. This is not directly supported within the STU3 Dosage structure.
Another clinical example would be for a Lidocaine medicated plaster. A typical written dosage instruction would be;
“Apply 2 patches once daily to the affected area for up to 12 hours, followed by a 12-hour plaster-free period; to be applied to intact, dry, non-hairy, non-irritated skin”
The FHIR STU3 Dosage structure can describe all the above except for the clause “followed by a 12-hour plaster-free period”. In a dose-based instruction this would needs to be expressed as free-text within a Dosage.additionalInstruction.