This code system http://hl7.org/fhir/v2/0251 defines the following codes:

CodeDisplay
DIProduct dose or frequency of use increased
DRProduct dose or frequency of use reduced
NNone
OTOther
WPProduct withdrawn permanently
WTProduct withdrawn temporarily

Additional Language Displays

Codenl
DIProductdosis of gebruiksfrequentie verhoogd
DRProductdosis of gebruiksfrequentie verlaagd
NGeen
OTAnders
WPProduct permanent teruggetrokken
WTProduct tijdelijk teruggetrokken