# Medication Regimens **Category:** [Technical (archive)](https://discourse.openehr.org/c/technical-archive/156) **Created:** 2004-10-11 20:08 UTC **Views:** 8 **Replies:** 2 **URL:** https://discourse.openehr.org/t/medication-regimens/14470 --- ## Post #1 by @Matias_Klein Hello All, We are currently working on an oncology project in which medication regimens are used\. I would appreciate some guidance on the preferred way to model regimens using openEHR\. Here is an example of a regimen I am modeling: Regimen Name: CAF Step 1: Cyclophosphamide 100 mg/m2/day po days 1\-14 Step 2: Doxorubicin 30 mg/m2/day iv days 1 and 8 Step 3: 5FU 500 mg/m2/day iv on days 1 and 8 repeat q 4 weeks As I see it, there are two possible models: 1\. One INSTRUCTION with an ITEM\_TABLE data structure that has each step in a different column\. OR 2\. Three INSTRUCTIONs with LINKs between them \(i\.e\. a "concurrent medication order"\)\. This would be very similar to the "chained medication order" described in the EHR Information Model \(Figure 27\)\. However in this case, the LINKs' meaning would be "concurrent actions" rather than "next action"\. Does anyone have a preference or another way to model this? Thanks, Matias --- ## Post #2 by @thomas.beale Matias Klein wrote: > Hello All, > > We are currently working on an oncology project in which medication regimens are used\. I would appreciate some guidance on the preferred way to model regimens using openEHR\. Here is an example of a regimen I am modeling: Matias, Sam Heard will provide an answer to your question in a couple of days \- he is currently in the UK after the recent CEN meeting, where apparently WG1 accepted the idea of including the ADL language specification in the standard as a normative part\. We have done some new work on how to represent the following kinds of drug regimens, and there will be a few changes to the openEHR reference model to support it\. Not too drastic, but simplifying\. Sam will provide a detailed response\. \- thomas --- ## Post #3 by @Sam Matias Thanks for the email \- and sorry to be so slow getting back to you\. Our current work in this area relates to instructions as a generic class in the reference model\. The links between individual instructions can modelled in a number of ways: 1\. The start condition for one instruction might be the start of another \(paralell\) or the completion of another \(chained\) 2\. A set of instructions might have overlapping start and finish \- that is they have no relationship other than the fact that they occur at the same time\. 3\. A section \- perhaps called 'Regime' could contain linked medications\. 4\. A link could be used\. >> We are currently working on an oncology project in which medication regimens are used\. I would appreciate some guidance on the preferred way to model regimens using openEHR\. Here is an example of a regimen I am modeling: >> >> Regimen Name: CAF >> Step 1: Cyclophosphamide 100 mg/m2/day po days 1\-14 >> Step 2: Doxorubicin 30 mg/m2/day iv days 1 and 8 >> Step 3: 5FU 500 mg/m2/day iv on days 1 and 8 repeat q 4 weeks >> >> As I see it, there are two possible models: >> >> 1\. One INSTRUCTION with an ITEM\_TABLE data structure that has each step in a different column\. The way we are modelling instruction would mean that this must be two separate instructions \- as the frequency of the action specified is held in the timing part of the instruction and must apply to the complete action\. A regime could be displayed in this manner\. >> OR >> >> 2\. Three INSTRUCTIONs with LINKs between them \(i\.e\. a "concurrent medication order"\)\. This would be very similar to the "chained medication order" described in the EHR Information Model \(Figure 27\)\. However in this case, the LINKs' meaning would be "concurrent actions" rather than "next action"\. Any instruction with the same timing is concurrent by definition \- the question is \- do we need to know that they are linked in a way that is more than concurrent timing\. I think not, apart from the ability to link these as you describe \- have the same indication and be organised as a regime or course or other grouping as required\. >> Does anyone have a preference or another way to model this? >> >> Thanks, >> >> Matias >> Cheers, Sam --- **Canonical:** https://discourse.openehr.org/t/medication-regimens/14470 **Original content:** https://discourse.openehr.org/t/medication-regimens/14470