Published: 1 December 2016
Revised: 13 February 2017
Guidance for Pharmacists Dispensing Prescriptions for Span-K
There was a recall in December 2016 involving the product Span-K due to manufacturing issues, meaning that
Span-K is not currently available in the New Zealand market. There are alternative slow release potassium
chloride supplement tablets available (Duro-K and Slow-K) that are funded by PHARMAC, but which do not have
consent for distribution in New Zealand.
Regulation 42(4) of the Medicines Regulations 1984 enables pharmacists to substitute a prescribed brand
where the provisions of regulation 42(4) are met.
42(4) If an authorised prescriber or a veterinarian refers in a prescription to a
medicine by its trade mark or trade name, or by reference to the name of its manufacturer, a pharmacist may
supply an alternative brand of medicine, provided that —
- the authorised prescriber or veterinarian has not marked the prescription "No brand substitution
permitted" or with words of similar meaning; and
- the substituted brand contains the same active ingredient or active ingredients, and no other active
- the substituted brand is in the same dose form and strength as the prescribed brand; and
- there is no clinical reason why the substituted brand should not be supplied; and
- the pharmacist records the brand substitution on the prescription; and
- the pharmacist signs and dates the prescription; and
- the pharmacist informs the patient of the brand substitution.
Section 29 of the Medicines Act 1981 (the Act) requires medical practitioners to request a supply of a
non-consented medicine for a patient, before it is provided.
It is noted that generally medicines considered for substitution under regulation 42(4) would exclude
non-consented medicines, as their clinical safety and efficacy has not been assessed by Medsafe.
In this case only, it has been considered that substitution of Duro-K or Slow-K to replace Span-K will be
clinically acceptable, but will require the agreement of the prescriber before substitution can occur. The
patient will also need to be informed that the product being supplied does not have consent for distribution
in New Zealand, but that the prescriber has agreed to it being supplied as an acceptable alternative.
Pharmacists are expected to apply their professional clinical judgement in each case, but should note the
- As Duro-K/Slow-K do not have consent for distribution in the New Zealand market, product would be
supplied under section 29 of the Medicines Act 1981 (the Act).
- Duro-K/Slow-K are consented medicines in Australia and product from Australia is being imported as
an alternative treatment until an alternative approved product becomes available.
- The effervescent potassium chloride supplement that has consent in New Zealand is not considered to
be a clinical equivalent to be used as a substitute.
When the product Duro-K or Slow-K is substituted for Span-K (either against a new prescription or a repeat
supply on an existing prescription) the following must be followed:
- The prescriber is contacted by the pharmacist to discuss the situation (to ensure they are aware that
the Duro-K/Slow-K is a non-consented medicine)
- The prescription is endorsed by the pharmacist with:
- the requirements of regulation 42(4)(i.e. the brand Duro-K/Slow-K, pharmacist signature and date).
- the time, date and name of the prescriber who has provided permission for the substitution
- The name and address of the patient and the name of the medical practitioner is provided to the
supplier of the medicine as required when supplying medicines under section 29 of the Medicines Act.
- The patient is fully counselled to make them aware that they will be receiving a non-consented
medicine, the reasons why and that the prescriber has given their permission for the substitution.