| Of the 13,000 medicines currently licensed for use in the UK,
oral methotrexate is one of only six that should be taken weekly. Its
unusual dosing regimen
has been the cause of many adverse incidents and has contributed to 25
patient deaths and 26 cases of serious harm over the past 10 years.
Because of this, methotrexate has been chosen as the subject of the latest
patient safety alert to be issued by the National
Patient Safety Agency.
As with the implementation of a previous alert for potassium
chloride solution (PJ, 27 July 2002, p122), pharmacists look set to play a central
role.
Three main approaches to tackling methotrexate’s safety problems
have been identified. The first is to provide better patient information.
The second is to improve the warnings and alerts used within prescribing
and dispensing software programs. The third is to develop more patient-friendly
packaging.
With these approaches in mind, the safety alert asks NHS acute trusts,
primary care organisations and local health boards to:
· Agree local action required
· Provide patient information before and during treatment
· Update software programs
· Review purchasing
So how do pharmacists fit in? Wendy Harris, senior pharmacist at the
NPSA, says pharmacists will help to implement the alert through their
role on locally managed drug and therapeutics committees. More generally,
pharmacists are being called on to assess the needs of patients being
treated with methotrexate. “The key role will be in reviewing prescriptions,” says
Ms Harris.
“This will mean checking with patients that they understand how
to take their medicine and checking that they are having their blood
monitored
regularly, since toxic build up can occur quickly.”
To help implement the alert, the NPSA has produced templates for the
core patient information that it expects patients to receive. Local drug
and therapeutics committees can adapt the patient information with localised
details, such as telephone help-lines or clinic opening hours. These
documents should then be circulated to GPs and community pharmacists.
To improve patient safety further, the alert recommends use of a patient-held
monitoring and dosage record. Again, a template has been produced by
the NPSA and this should be made available to all relevant clinicians.
The NPSA has also published a checklist for safe dispensing (see Panel
below).
Safe dispensing checklist
· Check for dose changes recorded on patient-held monitoring
and dosage record
· Assess patient’s needs in terms of packaging, labelling
and patient information
· Supply consistently so patient receives the same strength of
methotrexate each time
· Ensure patient can differentiate between methotrexate and folic
acid packaging
· Look for signs of methotrexate toxicity, eg, breathlessness,
dry persistent cough, vomiting |
Dispensing software upgrades
Of the 137 methotrexate-related incidents identified by the NPSA, 67
per cent were as a result of the wrong frequency being prescribed or
no frequency being stated on the prescription. But it is not only GP
systems that are lacking. “The fact that some patients died because
of [these prescribing errors] means that the barrier that pharmacists
provide was breaking down too,” says Ms Harris.
Work is already under way to update prescribing and dispensing software
to ensure it contains adequate alerts. The NPSA has collaborated with
systems suppliers to develop appropriate safety features and it is now
up to users of the systems to ensure upgrades are applied locally. (EMIS
prescribing systems have been updated automatically.)
Pharmacists with dispensing systems that use the First Data Bank Europe
Multiplex Drug Data File will be able to request updates as well as a
toolkit to support implementation.
Although the NPSA has a certain amount of clout when it comes to GPs,
pharmacists are being asked to implement these changes as a matter of
good practice. There is no national specification for community pharmacy
IT systems so the NPSA has listed its recommendations in a report, “Towards
the safe use of oral methotrexate”, that accompanies the alert
(available here).
One of the main features recommended by the NPSA is that when methotrexate
is selected by a prescriber or pharmacist a reminder appears on screen
stating that the dosage is usually weekly and that patients require regular
monitoring and blood tests.
Other ways in which software can help, include not allowing prescriptions
to be generated too frequently (ie, before the next prescription is due),
not allowing simultaneous prescribing of different formulations of methotrexate,
and linking prescriptions to clinical audit and monitoring.
Practical issues surrounding use
of oral methotrexate
As part of its work to promote safer use of methotrexate
the NPSA commissioned research into whether patients could actually
take their medicine. Methotrexate is used for severe rheumatoid
arthritis and, because of the dosing frequency, is often prescribed
in small quantities.
The research revealed that a large proportion of patients could not open
the container in which methotrexate was supplied to them by their pharmacist
(often the smallest tablet bottle available). A severely arthritic hand
can neither grip the small bottle, nor apply the pressure needed simultaneously
to open the lid. Wendy Harris, NPSA, says: “Pharmacists need to
find out what manual limitations a patient has.” The answer might
simply be to move up to the next sized bottle and change the lid. If
the problem is not addressed patients may decant their tablets into another
container. This can have disastrous consequences.
Ms Harris described how one patient decanted her methotrexate tablets
into an old tablet bottle labelled for a previous trimethoprim prescription.
The patient was subsequently admitted to hospital, taking her tablets
with her. Trimethoprim was added to her drug chart and the contents — methotrexate — administered
twice daily in accordance with the label. “Patients should not
have to revert to this kind of coping strategy,” says Ms Harris.
|
Purchasing review
Another approach that should be used to reduce harm is to review purchasing
practices. Purchasers should select products so that different strength
tablets are visually distinct and they should ensure packaging includes
the dosage warning required by the Medicines and Healthcare products
Regulatory Agency.
The NPSA is working with manufacturers to develop safer packing — original
packs that contain fewer tablets will reduce the need for pharmacists
to repack methotrexate. This will address some of the practical difficulties
patients face when trying to open tablet bottles (see Panel right). Original
pack dispensing will also reduce the likelihood of patients overriding
dosage instructions because dosage warnings will be reinforced. Furthermore,
it will reduce the need for staff to handle a cytotoxic drug.
The NPSA expects the NHS in England and Wales to have implemented the
action points set out in its alert by March 2005. To do this they will
need pharmacists to be on board.
News, p137 |
The
Pharmaceutical Journal