Brandon Toner

Using Potential Drug Therapy Problems (pDTP) to Prime for Care Planning Services


Drug Therapy Problems (DTPs) are the pharmacist's assessment of issues related to drug therapy that are in the way of achieving the patient's goals of therapy.

Identifying drug therapy problems relies on conducting a comprehensive patient assessment (elicit information).

This works well if the pharmacist has a planned assessment appointment with the patient. It becomes more challenging during ongoing care and monitoring activities within a community pharmacy where there may not always be routine clinical appointments scheduled with the pharmacist for each patient (like in a physician's clinic).

Community pharmacists are in an excellent position to monitor ongoing medication use. By assessing the patient's dispensing record, in combination with the clinical information documented on file, and information gathered through interactions with the patient, the pharmacist can identify potential drug therapy problems — clues that there may be an actual drug therapy problem.

What is the difference between a potential and an actual drug therapy problem? — clarity and depth of assessment.


While processing a routine request for medication refills, you notice that it's been a while since Mrs. Smith has filled her amlodipine (it's been 120 days since she filled a 90 days supply).

Is there a drug therapy problem here?

We don't know for sure! We need more information.

There are many possible DTPs and non-DTPs here, and the only way to know for sure is to assess the patient to get more information.

So, why are pDTPs important?

Potential drug therapy problems:

While actual drug therapy problems suggest changes to the patient care plan, potential drug therapy problems suggest further investigation of the area of concern.

Actual DTP: "Mrs. Smith is experiencing periodic orthostatic hypotension due to excessive antihypertensive use (amlodipine 10mg once daily, taken inconsistently due to dizziness) and may benefit from a dosage reduction."

Potential DTP: "Potential non-adherence: amlodipine (~30 days late on 90 day supply) — may benefit from further assessment at next opportunity"

Integrating pDTPs into Community Practice

Documenting pDTPs and programming them to alert pharmacy staff during the appropriate context empowers the team to clarity the patient record and identify any actual DTPs that the patient may be experiencing.

pDTPs could be reviewed during Med Review encounters, or during Prescription Renewals.

The particular approach to managing DTPs will ultimately depend on the potential severity of the issue, the degree of clarity, and the resources available.

i.e. A clear and significant problem should be addressed earlier than an uncertain and relatively minor concern.

Ultimately, the routine documentation of pDTPs creates the opportunity for more targeted deployment of pharmacy resources to conduct care activities for the population of patients on the pharmacy's care roster.

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