Diabetes in Pets
Insuvet Protamine Zinc
PZI by Pfizer Animal Health
long-acting Bovine
U100 protamine
Line Insuvet
Also known as Insuvet PZI, beef PZI
Similar to  
Action in cats  
  • onset 2-5h[1],
  • peak 12-24h
  • duration: maximum 36h
Action in dogs  
  • onset 2-5h,
  • peak 12-24h,
  • duration: maximum 36h-rarely used[2]
Use and Handling
Type cloudy
Shelf Life 24 months
When opened 28 days
In pen N/A

One of the products in the Insuvet product line, this is a pure bovine U100 Protamine Zinc insulin (PZI)[3][4], for veterinary use and available in the UK only from veterinary clinics[5].

Technical details

NOAH Compendium-UK[6] officially describes it as highly purified bovine protamine zinc (PZI) insulin, according to British Pharmacopeia (BP) standards and definitions. It is U100 strength and presented in 10ml vials. It is described[7] as being a medium to long lasting insulin, with onset from 2-5 hours after injection, peak at 12-24 hours, and maximum duration of 24-36 hours.

NOAH goes on to say that onset, peak and duration times have been reported as being variable in dogs. There is also a note regarding the time activity profile information for cats--times for them can be half that of dogs, due to cats' faster metabolism.

Usage and handling

Dosage information[8] for Insuvet Protamine Zinc PZI.

This insulin[9] insulin is to be given subcutaneously only.

Store at[10]2-8C; do not freeze. Insuvet Protamine Zinc needs rolling. Product should not be used if it does not re-suspend. The vial has a life of 28 days after first use and a shelf life of 2 years[11].

Comparable insulins are: Hypurin Vet Protamine Zinc (also for veterinary use) and Hypurin Bovine Protamine Zinc[12], which is approved for human use. The latter is the only one which can be exported from the UK. The U100 strength of BCP PZI and Summit PZI is also comparable to this insulin.

Feline insulin compared with Bovine, Human, & Porcine versions. Up to 4 amino acids differ. The closest match is bovine with only one amino acid difference; the lease close is human with four amino acid differences.

Insuvet PZI comes in a 10ML vial. It should be kept refrigerated and rolled gently several times before use to insure it is well-mixed and shows a uniform milky consistency. It will lose its efficacy within 24 hours if left out of the fridge. There is some debate how long it will last if it is stored correctly -- my vet says it should be good for 2 months.

No Combining For PZI

Protamine Zinc PZI[13] insulin cannot be combined with other insulins, due to the amount of protamine in the insulin's formula[14][15][16].

In the UK, it's in stock and can be obtained at Best Pet Pharmacy.

Further Reading