Understanding and Using ProZinc (PZ) Insulin
ProZinc (often shortened to PZ) is a long-acting insulin specifically approved for managing feline diabetes. It’s made from recombinant human insulin and is designed to help reduce high blood sugar levels in diabetic cats. PZ must be prescribed by a licensed veterinarian and is intended for cats only.
What It Looks Like:
ProZinc is sold in a 10 mL vial and should come in a sealed manufacturer’s box. Be cautious if your vet offers repackaged insulin, even in sterile containers—doing so can affect the quality and shelf life of the insulin.
How to Store and Handle PZ:
Even though ProZinc is fairly stable, it’s still important to store and handle it correctly:
How Long Will It Last?
Syringe Tips:
ProZinc is a U-40 strength insulin, meaning U-40 syringes are preferred for accurate dosing. In the U.S., U-40 syringes often have red caps. Some U-40 syringes also come with half-unit markings, which can help fine-tune dosing.
If you decide to use U-100 syringes (which typically have orange caps), you MUST use a conversion chart to adjust the dose correctly. U-100 syringes are sometimes chosen for their finer markings, but mistakes in conversion can lead to under- or overdosing. Most people do best sticking with U-40 syringes when using PZ.
Quick Tips:
Feel free to ask questions if anything here is unclear, or if you’re unsure about storage, dosing, or what to look for in a used vial. You’re not alone—many of us have learned all this the hard way, and we’re here to help!
- Tim
Change Log:
Created on 5/19/2025.
Sources:
Feline Diabetes Message Board. “Insulin Care and Syringe Info: Proper Handling and Drawing.” FelineDiabetes.com, 11 Apr. 2020, Sticky - INSULIN CARE AND SYRINGE INFO Proper Handling and Drawing | Feline Diabetes Message Board - FDMB.
ProZinc (often shortened to PZ) is a long-acting insulin specifically approved for managing feline diabetes. It’s made from recombinant human insulin and is designed to help reduce high blood sugar levels in diabetic cats. PZ must be prescribed by a licensed veterinarian and is intended for cats only.
What It Looks Like:
ProZinc is sold in a 10 mL vial and should come in a sealed manufacturer’s box. Be cautious if your vet offers repackaged insulin, even in sterile containers—doing so can affect the quality and shelf life of the insulin.
How to Store and Handle PZ:
Even though ProZinc is fairly stable, it’s still important to store and handle it correctly:
- Keep it refrigerated at 36–46°F (2–8°C) and away from light.
- Do not freeze. If it freezes, it’s no longer usable.
- Store it upright and never shake the vial. Instead, gently roll it to mix before each use.
- Inspect it before giving a dose: it should look evenly cloudy once mixed. If you see clumps or particles that don’t mix in, it’s time to replace the vial.
- If insulin changes color, the rubber stopper is damaged, or you see floating debris—it’s no longer good.
- A new vial may seem stronger at first, so test carefully in the first few cycles.
How Long Will It Last?
- An unopened vial is good until the expiration date on the box (if stored properly).
- Once in use, many caregivers find a single vial lasts up to 6 months if handled well.
- If blood sugar suddenly becomes difficult to regulate, that could be a sign your insulin has lost effectiveness—even if it's within that 6-month window.
Syringe Tips:
ProZinc is a U-40 strength insulin, meaning U-40 syringes are preferred for accurate dosing. In the U.S., U-40 syringes often have red caps. Some U-40 syringes also come with half-unit markings, which can help fine-tune dosing.
If you decide to use U-100 syringes (which typically have orange caps), you MUST use a conversion chart to adjust the dose correctly. U-100 syringes are sometimes chosen for their finer markings, but mistakes in conversion can lead to under- or overdosing. Most people do best sticking with U-40 syringes when using PZ.Quick Tips:
- Never squirt excess insulin back into the vial—doing so may contaminate it.
- Don’t pre-fill syringes. The silicone coating in syringes can degrade the insulin over time.
- Don’t dilute or mix ProZinc with other insulins or liquids.
- Keep a close eye on your cat’s blood glucose, especially when starting a new vial or adjusting the dose.
Feel free to ask questions if anything here is unclear, or if you’re unsure about storage, dosing, or what to look for in a used vial. You’re not alone—many of us have learned all this the hard way, and we’re here to help!
- Tim
Change Log:
Created on 5/19/2025.
Sources:
Feline Diabetes Message Board. “Insulin Care and Syringe Info: Proper Handling and Drawing.” FelineDiabetes.com, 11 Apr. 2020, Sticky - INSULIN CARE AND SYRINGE INFO Proper Handling and Drawing | Feline Diabetes Message Board - FDMB.