The prescribing cascade for veterinary medicines (VMGN 13)

Veterinary medicines guidance note for vets about how to use the prescribing cascade for veterinary medicines.

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Guidance on the use of the cascade

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The cascade is a provision in the Veterinary Medicines Regulations (VMR) that allows a vet to prescribe medicines that would not otherwise be permitted.

The principle of the cascade is that, if there is no suitable veterinary medicine authorised in the UK to treat a condition, the vet responsible for the animal can, to avoid causing unacceptable suffering, treat the animal in the order of consideration below;

  • a veterinary medicine authorised in the UK for use in another animal species or for a different condition in the same species.

If there is no such product, either:

  • a medicine authorised in the UK for human use, or
  • a veterinary medicinal product (VMP) not authorised in the UK but authorised in another European country for use in any animal species (in the case of a food-producing animal the medicine must be authorised in a food producing species) in accordance with an import certificate issued by the Veterinary Medicines Directorate (VMD).

  • The last option is a medicine prescribed by the vet responsible for treating the animal and prepared especially on this occasion (known as an extemporaneous preparation or special) by a vet, a pharmacist or a person holding an appropriate manufacturer’s authorisation.

In exceptional circumstances, medicines may be imported from outside Europe through the VMD’s import scheme.

As a vet prescribing for, or administering a medicine to, food-producing animals under the cascade you are required to specify an appropriate withdrawal period to the animal produce. When setting the withdrawal period, you must take into account known information about the use of the product on the authorised species when prescribing for another species.

There are specific labelling requirements for products used under the cascade and for record keeping.

Published 31 July 2013