Re: [Gnumed-devel] clin_medication

[Ian Haywood]

Karsten Hilbert wrote:

> > What field  should carry the bid tid etc?
> clin_medication.directions - free text
This is ambiguous: the same data is being stored twice.
The client should parse the directions string for bid tds etc. and
then *remove* those words from the comment. The comment is
for stuff that can't be broken down into the structure.

> dosage_form text
>
>                 not null, --check (form in ('spray', 'cap', 'tab', 'inh', 
> 'neb', 'cream', 'syrup', 'lotion', 'drop', 'inj', 'oral liquid'))
We should try to rationalise this list to forms [=Preparation] where the 
distinction is clinically significant, viz.
   tab -- all *solid* objects designed for oral or sublingual use, 
including capsules
   syrup -- all *liquid* drugs for oral ingestion
   cream -- all creams, lotions, solutions, tars, shampoos and pastes 
for  putting on skin or hair.
   supp -- suppositories and peissaries
   neb -- solutions for use in a nebuliser
   inh -- all other inhalers, MDIs, Turbuhalers, etc.
   drop -- drops for eyes/ears
   IV -- all solutions/drugs/dissolvable powders for IV/IM injection
   inj -- solutions specifically *not* for IV inection (think: 
vaccines, procaine penicillin)
   patch -- transdermal patches, e.g. GTN, fentanyl, oestrogen


> --      is_SR boolean   -- ???
Some drugs have both a slow-release and standard preparation available 
under the same brandname,
for some (tramadol, sertraline) distinction is crucial.

> we want it to tell us what each drug contains ? No (but we want
> the widget to allow us to *jump to* that information in
> Hilmar-space). Will there be cases where more detail is needed
>  
Yes, but, IMHO we need enough information to find the preparation (or 
clinically equivalent preparation)
in any database, otherwise we are locked in by our own records. You have 
a suitable non-vendor specific
ID (PZN), we don't. ATC is nearly, but not quite, specific enough, hence 
my desire to replicate a lot of drugref stuff.
PBS item codes are specific, and sound like the analogue of PZN, but 
only cover drugs subsidized by the government.

> Am I thinking correctly that when we prescribe generics we
> would do this:
>
> phenoxymethylpenicilline 1.5 Mio i.E.
> clavulanic acid 3g
>
> which being TWO SEPARATE ROWS in clin_medication ?
> Whereas when I would prescribe a particular drug by brand name
> containing both of the above it would be just one row. This is
> how I designed the table anyways
IMHO bad, as this means duplicates of all the other fields, poor 
normalisation in other words.
A linked separate table is the SQL-pure way of representing this data, 
but I understand your relunctance.

Perhaps the generic text field can be upgraded to a parseable "generic 
drug expression"
such as "amoxycillin 875mg/clavulanic acid 125mg", effectively a 
name-based substitute of PZN, which is also poor normalisation of 
course, but doesn't pollute the schema with what is, I have realised, a 
hack around the incompetence of my own just re-elected government [sob]

Ian