Scripts from Vets

Scripts from Vets are NSS. Enter the Vet in through the Doctor Utility and choose the 'Health Professional' as 'Vet'

From the Regulations (courtesy of the Euan Galloway ex PSNZ)

You won't find anything like period of supply in the vet regulations, compared to the medicines regs they are very "loose" about prescribing and supplying. Looking at the medicines regs, 1 year's supply could be prescribed PROVIDED the prescription specifies the total amount of medicine that may be sold or dispensed, or the total period of supply AND the quantity is appropriate for the treatment prescribed as judged by the Veterinary Council Code of Professional Conduct - "Veterinarians must exercise sound professional judgement when authorising, dispensing, recommending, selling and using veterinary medicines." 

The 6 months story has probably come about by pharmacists not reading the full sentence of Medicines Regulations 42(3)(c) - "a prescription for a medicine other than an oral contraceptive must not be dispensed on any occasion after 6 months have elapsed from the date on which it was printed or, if given under regulation 40A(1), communicated orally" and confusing the act of dispensing with the prescribed period of supply.

Medicines Regulations 39(3)

A veterinarian may only prescribe a prescription medicine that is for the treatment of an animal under the veterinarian's care (Medicines Regulations 41(f)). Every prescription given under these regulations shall ... (f) indicate the total amount of medicine that may be sold or dispensed, or the total period of supply; Medicines Regulations 42(3)(c)Every person dispensing a prescription relating to a prescription medicine must comply with the following requirements:

• a prescription for a medicine other than an oral contraceptive must not be dispensed on any occasion after 6 months have elapsed from the date on which it was printed or, if given under regulation 40A(1), communicated orally ***  

The short answer is: a quantity of a prescription medicine that appropriate for the treatment of that animal, and the quantity shall be specified on the prescription.  Repeats can be prescribed, but the prescription (i.e. the piece of paper that is the authority for you to supply that prescription medicine on any occasion) is valid for only 6 months from the date on which it was written.  

What quantity is appropriate for the treatment prescribed would be judged by the Veterinary Council Code of Professional Conduct.  See http://www.vetcouncil.org.nz/CPC/VetMed/CPC_VetMedicines.php 

Note that Regulation 39A - Limit on period of supply of prescription medicines(1) An authorised prescriber may not on any occasion prescribe for any patient a quantity of any prescription medicine that exceeds(a) 6 months' supply in the case of an oral contraceptive; or(b) 3 months' supply in any other case.applies ONLY to authorised prescribers.  A vet is not included in the definition of an authorised prescriber. Medicines ACT section 2:authorised prescriber means a practitioner, registered midwife, or designated prescriber.practitioner means a medical practitioner or a dentist.