Compounding for pets: how veterinary compounded medicines help cats, dogs and other animals

Why animals so often need compounded medicines

Manufacturers make medicines for people first. That leaves gaps that matter a great deal for animals:

• Tiny or unusual doses — a 4 kg cat or a 900 g guinea pig may need a fraction of the smallest tablet made.
• Palatability — try getting a cat to take a bitter tablet twice a day. Flavoured liquids and treats (chicken, beef, fish, cheese) change compliance completely.
• Dosage forms — transdermal gels applied to the ear, oral suspensions, or capsules sized for small animals.
• Species differences — some human excipients (for example the sweetener xylitol) are toxic to dogs; a compounded preparation can avoid them.
• Discontinued or unavailable products — including during shortages of veterinary lines.

How it works in Australia

Veterinary compounding follows the same principle as human compounding: it's used when there is no suitable registered veterinary (or, where legally permitted, human) product. The prescription comes from a registered veterinarian, and the pharmacist assesses and prepares the medicine for that specific animal. Veterinarians register for the CustomDose prescriber portal with their state veterinary board registration number.

For pet owners

If your vet has prescribed a compounded medicine, you can send us the prescription the same way as any other — photo, PDF or e-script — with your details and your pet's name and date of birth on the script. A pharmacist reviews it, you receive a payment link once approved, and the medicine is prepared and dispatched. Storage instructions and dosing devices (oral syringes, applicators) are included.

For veterinarians

The prescriber portal lets you browse available dosage forms and flavours, generate a signed script in a couple of minutes, keep a per-patient history and ask a compounding pharmacist about formulation questions — stability, concentration limits, flavour options for a particular species, and so on.

Common questions from owners

• How do I give a transdermal gel? Usually a measured amount rubbed into the hairless inner ear, wearing a glove, alternating ears. Full directions come with the medicine.
• How long does a flavoured liquid last? Compounded liquids have a defined beyond-use date, typically shorter than commercial products; it's on the label.
• Can I get the same medicine cheaper elsewhere? If a registered product suits your pet, that is what should be supplied — we'll tell you if so.