Prescribing and Pharmacotherapeutics

A safe prescription is more than a drug, dose, and signature. It is a reasoned decision that links the patient's diagnosis and treatment goal with pharmacokinetics, pharmacodynamics, comorbidities, concurrent therapies, monitoring capacity, and the prescriber's legal authority. For a Canadian nurse practitioner, authority is layered. Federal law recognizes NPs as practitioners for specified controlled substances, but the province or territory in which the NP is registered must also permit prescribing that substance. Neither level of authority can be assumed from the other. Controlled-substance prescribing is also not the same as authorization to compound or sell controlled substances. Provincial requirements may add education, formulary, specialty, or practice-setting restrictions; for example, Ontario requires approved controlled-substances education before an NP can prescribe controlled drugs and substances, and British Columbia bounds NP prescribing through BCCNM standards, limits, and conditions. The medication decision must then be checked against Canadian evidence and the current Canadian Product Monograph. The monograph, rather than foreign labelling, supplies the Canadian indication, dose, contraindications, warnings, and interaction information. This matters because safety labelling changes over time. A prescription that was reasonable...