Extemporaneous preparation of methadone mixture
The Code of Ethics and Standards requires that when supplying prescribed
medicines, pharmacists must supply a product with a marketing authorisation,
where such a product exists and is available, in preference to an unlicensed
medicine or food supplement. Pharmacists should only prepare a product
extemporaneously if there is no product with a marketing authorisation
available and where they are able to prepare the product in compliance
with accepted standards.
An exception to these requirements, to permit the extemporaneous preparation
of methadone mixture in circumstances where a licensed product is available,
will be granted provided the following requirements are adhered to:
(a) If a licensed product is available, methadone mixture may only be
prepared extemporaneously if the quantity of methadone dispensed on a
regular basis is large enough to preclude storage of sufficient quantities
of the licensed product within the pharmacy, in accordance with the safe
custody requirements of the Misuse of Drugs legislation.
(b) In addition to the standard operating procedures (SOPs) required
for dispensing, a SOP must be in place for the extemporaneous preparation
of methadone. The SOP must ensure safe systems and provide a verifiable
audit trail. Adherence to the SOP must be ensured.
(c) Extemporaneous preparation must only be carried out by persons who
are appropriately trained and competent to do so.
(d) All quantities of methadone powder and diluent, and any colourings,
flavourings and stabilisers, must be accurately measured. Wherever possible
all measurements should be checked by a second person. (Pharmacists must
not rely on the accuracy of the quantities of powder, diluent etc stated
on the manufacturers packs.)
(e) The equipment used to measure and prepare extemporaneous methadone
products must be appropriate and be maintained in good order to ensure
that performance is unimpaired.
(f) Equipment must be properly cleaned between each batch of extemporaneously
prepared product to ensure that no residue from previous batches remains.
(g) Visual checks must be made to ensure the methadone powder has fully
dissolved in the diluent.
(h) Stock bottles must not be reused.
(i) The product must be labelled with the necessary particulars, including:
- The name and strength of the product
- The quantity of medicinal product
in the container
- Any special handling
and storage requirements (eg, store in safe custody)
- The batch expiry date
- A batch reference number
(j) For each batch of extemporaneous methadone mixture prepared a record
must be maintained for a minimum of two years but, if possible, for
five years of:
- The formula
- The ingredients and quantities used
- The source, batch number and expiry date of the ingredients
- The batch number and expiry date of the extemporaneously prepared
mixture
- The persons involved in preparing the product, including the
identity
of the pharmacist assuming overall responsibility
(k) Extemporaneously prepared methadone mixture must be stored in a
cabinet, cupboard or room that meets the requirements of the Misuse of
Drugs (Safe Custody) Regulations 1973.
(l) Extemporaneous preparation of methadone mixture, when a licensed
product is available, carries increased liability and must be covered
by indemnity insurance arrangements.
(m) Running balances of methadone powder and the resulting extemporaneously
prepared methadone mixture should be maintained.
(n) The prescriber and the patient should be informed that the methadone
product being supplied does not have a marketing authorisation. |
The
Pharmaceutical Journal