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Using vet medicines

When you recommend, use, or authorise the use of products to treat animals, you have to meet certain legal requirements. The ACVM requirements are detailed on this page.

The Veterinary Council of New Zealand (VCNZ) Code of Professional Conduct also has guidance on how to prescribe and use veterinary medicines.

Code of professional conduct – VCNZ website

Managing product risks

As a veterinarian, you're an important risk manager for veterinary medicines. You need to:

  • consider and mitigate the risks that using a product might pose to public health, trade in primary produce, agricultural security, and animal welfare
  • give appropriate advice on managing residues and withholding periods in food-producing animals
  • manage risk when advising on using products off-label.

There are also risks around complying with conditions of:

  • product registration
  • exemption for exempt products.

For guidance on managing the product risks, refer to the information below:

Products exempt from registration

Products that fit one of the ‘exempt from registration’ categories in the ACVM (Exemptions and Prohibited Substances) Regulations 2011 are only exempt if the relevant exemption conditions are complied with.

Be aware of the exemption conditions if you're recommending or using exempt products.

Advice on magnesium products:

Magnesium supplementation in dairy cows [PDF, 198 KB]

Products that claim to treat pain or distress 

There are no exemptions in the regulations for products that claim to treat a disease characterised by pain or distress. These products must always be registered because of the animal welfare risks.

Registered veterinary medicines

Registered veterinary medicines all have registration conditions to manage risks. Some conditions apply directly to the responsible veterinarian. Make sure you know the conditions for every product you recommend, authorise, or use. This applies to over-the-counter products as well as restricted products. 

Check the ACVM product register for registered veterinary medicines and their conditions.

ACVM product register

Restricted veterinary medicines 

A ‘restricted veterinary medicine’ (RVM) is registered with extra restrictions on its sale, purchase, and use. Using these products poses greater risks than unrestricted products, which you need to manage.

If you're a veterinarian with a current practising certificate from the VCNZ, you can issue veterinary authorisations for the purchase and use of RVMs. This recognition carries significant legal obligations (in addition to authorisation). The obligations relate to managing sales, labelling, and recordkeeping. They're set out in this ACVM Notice:

Requirements for Authorising Veterinarians Notice [PDF, 223 KB] 

To help you authorise the use of veterinary medicines, we've got guidelines for issuing robust veterinary operating instructions (VOIs) for non-veterinarians to use for:

  • RVMs (including RVMs for velvet antler removal)
  • veterinary medicines that are exempt from registration subject to veterinary control.

Veterinary operating instructions guidelines [PDF, 231 KB] 

This authorisation recognition doesn't extend to selling RVMs. All selling activities (including distribution, storage, dispensing, and supply) are subject to the conditions of registration that specify who can sell RVM products.

Learn more about selling veterinary medicines

Antibiotics

Antibiotics are antimicrobials that kill or inhibit the growth of bacteria in animals and in New Zealand are classed as restricted veterinary medicines (RVMs). 

If you are a veterinarian authorising the use of antibiotics for animals under your care, you need to be aware of your legal responsibilities under the ACVM Act 1997. These include:

Vets also have obligations under the New Zealand Veterinary Council (VCNZ) Code of Professional Conduct for Veterinarians.

Code of professional conduct – VCNZ website

When authorising antibiotics, as a veterinarian you must:

  • only authorise RVMs (which includes antibiotics) for animals under your care
  • have enough information to support the therapeutic choice of the antibiotic and its authorisation
  • specify the total quantity of antibiotic authorised,
  • make sure the person administering the RVM is able to carry out the veterinarian’s instructions for use, and
  • ensure there is someone available to manage any adverse events or ongoing care needed to treat the animal or arrange for such care.

The Code of Professional Conduct for Veterinarians also states that a consultation is required to make sure there is enough information to support antibiotic use. This should include an understanding of the history of disease and treatment in the herd, flock, or animal(s) being treated.

When selecting an antibiotic, veterinarians should use the antibiotic with the lowest level of importance to human and animal health that will be effective against the disease to be treated, while following the prescribing cascade in the Code of Professional Conduct for Veterinarians. Good antimicrobial stewardship practices like this help reduce the risk of antimicrobial resistance. Inappropriate antibiotic use can accelerate the rate of resistance occurring.

Antimicrobial resistance

Antimicrobial resistance (AMR) can reduce treatment effectiveness in both people and animals, leading to increased treatment costs, reduced welfare, and production outcomes. It’s important we all play our part to help keep antibiotics effective.

As a veterinarian you can help reduce AMR risks by:

  • helping animal owners and carers understand how antibiotic use contributes to antibiotic resistance
  • being sure there is a bacterial infection or known exposure to a bacterial pathogen to indicate an antibiotic is the appropriate treatment
  • referring to treatment guidelines for up-to-date recommendations of antibiotic choice, dose rate, dosing period, and route of administration
  • undertaking culture and sensitivity testing to confirm the pathogen and identify the appropriate treatment when required
  • checking there are no restrictions or contraindications for use of the antibiotic for the animal being treated
  • making sure the owner or carer can administer the antibiotic, and that they understand the importance of completing the course as directed. Show them how to correctly administer the treatment and ask them to seek help if they are having trouble.
  • ensuring owners or carers are aware of and understand the withholding periods when authorising antibiotic use in food-producing animals. Remember, this includes horses.
  • ensuring the shelf life of the product dispensed is long enough to cover the authorisation period
  • selecting the most appropriate antibiotic, without being influenced by non-clinical factors such as financial incentives, cost, or convenience.

For more information on antimicrobial stewardship, check out the MPI leaflet.

It's time to unite against AMR – information pamphlet for vets [PDF, 506 KB]

The AMR team at MPI have more information on antimicrobial resistance, antibiotic classification and reviews, as well as background policy, annual sales reports and the National Action Plan to deal with antimicrobial resistance on the AMR page.

Find out about antimicrobial resistance and using ACVMs

Deciding on treatment

When deciding what product to use, follow the risk management-based product-use cascade.

Risk management-based product-use cascade

Number 1 products should be your first choice. They've been ACVM risk-assessed for veterinary use.

  1. On-label use of a New Zealand-authorised (under the ACVM Act) veterinary product 
  2. Off-label use of a New Zealand-authorised veterinary product
  3. Off-label use of a New Zealand-authorised (under the Medicines Act) human medicine
  4. Import of an overseas product (veterinary product preferred but human product acceptable)
  5. Use of a compounded veterinary preparation.

Using products off-label

Off-label use means any change from following the written instructions for use provided with a product.

For example, the product might be used to treat a different problem that isn't listed, or a different dosage might be followed.

Before choosing to use a product off-label, carefully consider options. Don't use any registered veterinary medicine off-label unless you can justify and manage the risks.

If you're not recommending off-label use for a product but you're asked for advice about off-label use, you should:

  • be prepared to offer advice on use and withholding periods, or
  • advise against off-label use if there's a suitable alternative as per the cascade above.

Off-label use is prohibited for some products 

Some products are registered with conditions that prohibit using them off-label, for example:

  • Condition 31: This product must only be used as specified in the label content.
  • Condition 97: This product must only be used in the species identified on the label.

Check the conditions on any registered product you are considering using off-label.

ACVM product register

Off-label use and food-producing animals

If you're recommending or using a product off-label in a food-producing animal, you're legally responsible for determining a suitable withholding period (WHP) to manage residues and compliance with the maximum residue level (MRL).

Importing in special circumstances

If there isn't a suitable authorised product available in New Zealand for your treatment, you can request approval to import a product. This is done under the 'special circumstances' provision of the ACVM Act. Under the provision, MPI can allow the import, manufacture, sale, or use of an unauthorised veterinary medicine without registration.

You'll need a special circumstances approval granted by MPI before you can import products from overseas. There may also be other approvals needed from:

  • the Ministry of Health, and/or
  • MPI (under the Biosecurity Act), and/or
  • the Environmental Protection Authority (EPA).

This will depend on the product. Refer to the guideline and application form to find out more.

Agency contacts

Compounding veterinary preparations

Compounding means making, preparing, producing, or processing a veterinary preparation for animals you're treating. Veterinarians can compound veterinary preparations under the ACVM (Exemptions and Prohibited Substances) Regulations 2011. There are strict conditions and requirements around this. Compounding should only be done when no suitable product is available.

Our product-use cascade can help you decide what treatment to use.

Go to the product-use cascade 

If you plan to compound a veterinary preparation, use this guideline for information on your ACVM obligations and advice on developing a documented system:

Developing a documented system for compounded veterinary preparations [PDF, 209 KB]

Find out more about manufacturing veterinary medicines

Residues and withholding periods

The withholding periods (WHPs) on product labels are set based on the on-label use of the product. This ensures compliance with the maximum residue levels (MRLs) for the active ingredient(s) in the product.

The on-label WHPs are based on trial data that's evaluated as part of the product's registration. It may not be applicable to all clinical circumstances. If an animal is treated in a situation that doesn't fit the typical clinical circumstances (like when an animal shows signs of liver or kidney disease), consider extending the WHP.

Legal obligations around WHPs and off-label use

If you choose to use any product in an off-label or unapproved way, you're legally responsible for ensuring the WHP is appropriate to manage residues for all active ingredients administered. This includes using multiple products at the same time. Make sure you always record your WHP advice as part of the authorisation (for RVMs) and the clinical treatment record.

Food-producing animals

Refer to:

Selling veterinary medicines

Exempt from registration, unrestricted, and restricted veterinary medicines (RVMs) have different requirements when it comes to advertising and selling them.

Find out about requirements when selling veterinary medicines

Conducting trials

You can use a veterinary medicine as you see fit when responding to a clinical need, but you must manage the ACVM risks. Keep records of instructions, administration, adverse effects, and outcomes. 

You must not use treatments in response to a clinical need as field or clinical trials unless you have:

  • established a trial protocol, and
  • received Animal Ethics Committee approval before beginning the trial.

Check the New Zealand Veterinary Association guidelines.

Vist the NZVA website

If your trials involve unregistered veterinary medicines that would require registration (like medicines that wouldn't be exempt from registration if they were sold), you must get an MPI approval to conduct trial work on that medicine before beginning the trial.

Research on non-trade name products

Provisional registration

Adverse events

Adverse events include any unexpected outcome relating to:

  • efficacy
  • safety
  • residues.

They can stem from:

  • products you've authorised
  • unrestricted product use that has caused issues you become aware of (or have to treat for)
  • animal feeds issues you know about or treat for.

Get forms and guidelines and learn more about adverse events with ACVMs

Approved operating plans

An operating plan (OP) explains how an organisation will control activities they carry out. This includes:

  • the planning process for each individual activity
  • how the organisation plans to assess risk, and
  • how the organisation will record and internally audit the activities carried out under the OP.

You must have an MPI-approved OP when:

  • having and complying with an approved OP is a condition of product registration, like selling RVMs (as a veterinarian, you don't need an MPI-approved operating plan to sell RVMs if you only supply RVMs authorised by veterinarians in your practice)
  • having and complying with an approved OP is a condition of exemption from registration, like an approval in special circumstances, conducting research, testing, teaching, or training.

OP guidelines and forms

Keeping records

Good record-keeping is an essential part of risk management. The VCNZ Code of Professional Conduct has record-keeping advice, but for ACVM products, keep written records of:

  • instructions for use for RVM authorisations, and advice given for use of unrestricted products
  • instructions/use different from what is approved for the product (with reasons)
  • concurrent treatments
  • withholding period advice you gave
  • circumstances that make the case unusual.

Record-keeping for food-producing animals

The treatment of food-producing animals also has record keeping requirements under the Animal Products Act, especially if a risk management programme (RMP) applies.

Check the relevant requirements

MPI business units