1. Guidance for vets on prescribing under the cascade and VMIMS in Northern Ireland
Source: gov.uk (2025-11-12)

Prescribing processes for vets in Northern Ireland from 1 January 2026.

1.1 Prescribing processes from 1 January 2026

To ensure that the needs of animal health and welfare can continue to be met from 1 January, the Government is introducing two schemes for sourcing medicines in Northern Ireland in accordance with the Windsor Framework. The Veterinary Medicines Internal Market Scheme (VMIMS) removes the current requirement for a Special Import Certificate for products (other than vaccines) obtained from Great Britain. The Veterinary Medicine Health Situation Scheme (VMHSS) also does not require a Special Import Certificate for the EU products listed. (https://www.gov.uk/guidance/products-available-via-the-veterinary-medicine-health-situation-scheme-vmhss)

The flow chart below sets out in which circumstances you will have to apply for a Special Import Certificate. Vets can choose whether to use a product on the VMHSS, or should, in their clinical judgment, a more suitable product be available under the cascade/ VMIMS, they can instead turn to the cascade/ VMIMS.

The table below sets out in which circumstances you will have to apply for a Special Import Certificate. Vets can choose whether to use a product on the VMHSS, or should, in their clinical judgment, a more suitable product be available under the cascade / VMIMS, they can instead turn to the cascade / VMIMS.

*Vets do not have to prioritise the VMHSS to the cascade and may use their clinical judgment to decide which route is preferable.

** Not including GB vaccines

It remains the responsibility of the vet to determine the most suitable product for the patient under their care. Neither route for accessing veterinary medicines takes precedence. Vets can choose whether to use a product on the VMHSS, or should, in their clinical judgment, a more suitable product be available under the cascade, they can instead turn to the cascade.

We should also note that the decision on whether to add a product to the VMHSS rests with the VMD, but the VMD is always keen to understand from vets, farmers and other stakeholders whether there might be a need.

1.2. Timelines for obtaining a Special Import Certificate

Where a vet does require a Special Import certificate, they will have to apply via the portal (https://www.vmd.gov.uk/business/register/apply-for-a-special-import-certificate). The VMD will then consider this request and respond within the following timelines.

Table 1: Application assessment timetables

If we need to request further information or clarification from you, then we will suspend the timescale pending your response. We will give you a deadline to respond and if this is not met, we will refuse the application, and you will need to re-apply.

Where there is an immediate, clinically life-threatening need, email the VMD at xxx@xxx.xx (mailto:xxx@xxx.xx), include ‘urgent’ in the subject and provide an explanation.

1.3 Further information on holding a ‘reasonable quantity’ when importing products under the cascade

Vets may hold a reasonable quantity of stock of a particular veterinary medicine that they have obtained via the cascade. A ‘reasonable quantity’ remains based on a vet’s clinical judgement, as before. This is to ensure vets are not constricted by a specified amount that does not meet the clinical need and maintains their ability to obtain the products they require. For example, a reasonable quantity might be to maintain a buffer stock for routine treatments and emergencies.

1.4 Sourcing vaccines

If a vet is looking to source a vaccine that is not authorised in Northern Ireland from either Great Britain or the EU, they must apply for a Special Import Certificate (https://www.vmd.gov.uk/business/register/apply-for-a-special-import-certificate), unless it is listed under the Veterinary Medicine Health Situation Scheme. You check the Veterinary Medicine Health Situation Scheme list (https://www.gov.uk/guidance/products-available-via-the-veterinary-medicine-health-situation-scheme-vmhss) to see if products are available through this scheme.

Note you can source the products directly from a Great Britain or a Northern Ireland wholesaler. Northern Ireland based wholesalers can procure Great Britain products and hold them in stock where they expect they may be needed under the VMIMS.

1.5 Sources to support in monitoring veterinary medicine supply

The VMD monitors supply of veterinary medicines across the whole of the UK. Information on the current shortages (https://www.gov.uk/guidance/known-supply-problems-with-animal-medicines) of veterinary medicines is available. If you are experiencing or foresee any issues of short supply of any veterinary medicines, please let the VMD know by filling out the report a supply problem form. (https://www.gov.uk/government/publications/report-a-supply-problem-with-a-veterinary-medicine)

In addition, the Veterinary Medicine Directorate’s Product Information (https://www.gov.uk/check-animal-medicine-licensed) Database contains a comprehensive list of all veterinary medicines authorised in Great Britain, United Kingdom wide and most products for Northern Ireland. This is a searchable database, which can be searched by territory, by product, by active substance, by species, therapeutic group, VM number, MA holder, distributor, authorisation route, distribution category, pharmaceutical form, issue date and there is also a useful list of predefined searches available to select from. The database will also show which product authorisations have been expired and which have had their Marketing Authorisation Holder information updated ahead of the end of the grace period to be based in Northern Ireland or the EU. Note that products that have a UK-wide marketing authorisation (a ‘4000’ product) can continue to be marketed across both Northern Ireland and Great Britain after 31 December 2025.

For products that are authorised on an EU-wide basis, including Northern Ireland (centralised products), the Veterinary Medicines information website (https://medicines.health.europa.eu/veterinary/) should be used and more information on this is provided in the question below. This free-access website enables you to:
- search and view information on all authorised veterinary medicines in the EU / EEA, registered homeopathies and assorted other pet products
- consult product information and public assessment reports
- learn in which Member State a specific veterinary medicine is available
- find information which could help identify potential treatment alternatives
Any product obtained from the EU, which is not listed (https://www.gov.uk/guidance/products-available-via-the-veterinary-medicine-health-situation-scheme-vmhss) under the Veterinary Medicine Health Situation Scheme, requires a Special Import Certificate.

1.6 Withdrawal periods under the cascade or the VMIMS

A withdrawal period is the length of time that must lapse between the final administration of the medicine and the point that the treated animal can be slaughtered to enter the food chain or when produce is taken from the treated animal. The prescribing vet is required to specify an appropriate withdrawal period when prescribing or administering a medicine to food-producing animals under the cascade or the Veterinary Medicine Internal Market Scheme (VMIMS) (the process is the same).

If a medicine is being used as authorised (at the same dose, via the same route and in the species listed as laid out in the Summary of Product Characteristics (SPC)), the withdrawal period stated on the labels/SPC can be used. This includes medicines that are authorised in the EU and imported under a Special Import Certificate and products moved under the VMIMS.

If the medicine is not being used as authorised, the vet should consider Table 2.

Table 2: Withdrawal periods if the medicine is not used in line with the SPC

If the medicine is not authorised for animals producing eggs/milk for human consumption or the medicine is not authorised for food-producing animals. The active substance must still be on the allowed substances list in table 1 in the Annex to Regulation (EU) No. xx-xxxx-xxxx (https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32010R0037).

In addition, in both cases - whether the product is used in line with the SPC or not - the vet should also take into consideration the following factors:

Known information about the use of the product on the authorised species when prescribing for another species

Whether the medicine is being used in line with its SPC to ensure that no residues of veterinary medicines above the MRL remain at the time of slaughter or when produce is taken. This will need to be taken into account where a higher dose or longer duration of treatment is used, or in a species that is not indicated on the SPC

If the calculation of a withdrawal period results in a fraction of days, the withdrawal period must be rounded up to the nearest number of days

For milk, if the calculation of the period results in a milk withdrawal period not divisible by 12, the withdrawal period must be rounded up to the nearest multiple of 12 hours

If a higher dose is given, a longer withdrawal period may be necessary

Where the authorised withdrawal periods are close to, or longer than, the statutory minimum withdrawal periods, you should consider the length of the authorised withdrawal period(s) and the known pharmacokinetics of the active substance(s) in both the authorised species and the species being treated (if different)

There is full guidance on withdrawal periods (https://www.gov.uk/guidance/the-cascade-prescribing-unauthorised-medicines) and how they are used in conjunction with the cascade.

1.7 Withdrawal periods under the cascade or VMIMS: honey

As there is no statutory minimum withdrawal period set for honey, you must set a suitable withdrawal period that will ensure no risk to consumer health. The active substance must still be on the allowed substances are listed in table 1 in the Annex to Regulation (EU) No. xx-xxxx-xxxx (https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32010R0037). Further guidance is available from the National Bee Unit (http://www.nationalbeeunit.com/).

There is full guidance on withdrawal periods (https://www.gov.uk/guidance/the-cascade-prescribing-unauthorised-medicines) and how they are used in conjunction with the cascade.

1.8 Withdrawal periods under the cascade or VMIMS: horses

A horse declared as non-food producing in its passport can be treated as a non-food animal under the cascade. A horse that has not been signed out of the food chain in its passport must be treated as a food-producing animal under the cascade.

There is legislation which lists substances essential for the treatment of horses (https://www.legislation.gov.uk/eur/2013/122/contents). These substances can be used in horses declared as food or non-food producing in the passport under the cascade using a statutory withdrawal period of 6 months. See horse medicines and record keeping requirements guidance (https://www.gov.uk/guidance/horse-medicines-and-recording-keeping-requirements) page for more information about the use of medicines in horses.

Full guidance on withdrawal periods and how they are used in conjunction with the cascade can be found here. (https://www.gov.uk/guidance/the-cascade-prescribing-unauthorised-medicines)

1.9 Record keeping for products used under the cascade or the Veterinary Medicine Internal Market Scheme (VMIMS)

The VMIMS does not change expectations on vets in determining and recording clinical decision making when prescribing under the cascade (see here) (https://www.gov.uk/guidance/the-cascade-prescribing-unauthorised-medicines#record-keeping). Vets should continue to work down the cascade hierarchy to determine the appropriate medicine for the animal and condition presented and record this in patient records as now: Code of Professional Conduct for Veterinary Surgeons (https://www.rcvs.org.uk/setting-standards/advice-and-guidance/code-of-professional-conduct-for-veterinary-surgeons/supporting-guidance/clinical-and-client-records/) (Section 13).