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ProZinc (protamine zinc recombinant human insulin) U-40 Injectable for Dogs & Cats

By ProZinc
Rated 4.7928 out of 5 stars
Prescription Item


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$120.49Chewy Price
$114.47Autoship Price
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Usually arrives in 3-5 days
We'll collect your pet's prescription information at Checkout.

This item requires prescription approval.

This item is specially packaged to remain refrigerated during transit.

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About This Item


ProZinc is a protamine zinc insulin prescribed by veterinarians to help support the insulin levels of diabetic cats and dogs. A single ProZinc injection has an appropriate duration of activity (10-14 hours) in cats and an extended duration of activity (16-24 hours) in dogs, which helps to keep their blood glucose level consistent throughout the day. It contains recombinant DNA that mimics human insulin, so it helps to control your pet's diabetic symptoms and keeps them comfortable.

Proudly sourced directly from the manufacturer or their approved distributor. Guaranteed genuine and backed by the manufacturer.

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Play Video: Learn More About ProZinc From Our Team of Experts
Learn More About ProZinc From Our Team of Experts

About Prozinc

The Importance of Insulin

The hormone, insulin, gets glucose into cells so it can be used as an energy source. Diabetic pets either can’t produce enough insulin or don’t respond to it properly, and if they don’t get the insulin injections they need, they can suffer from serious health issues caused by high blood glucose. Closely follow your vet’s guidance on how to give PROZINC (protamine zinc recombinant human insulin).

Once Daily Use In Dogs

PROZINC was designed to help regulate blood glucose in dogs with just one injection each day.¹ You may not see results immediately, as it can take up to 6 weeks for insulin to regulate blood glucose. Talk to your vet about what to expect when you begin PROZINC and ask how long it may take for your dog to achieve regulation.

Fast in Cats and Affordable

FDA-approved PROZINC helps control diabetic symptoms quickly in cats, and you may see improvement in as little as 7 days. It can help decrease the excessive thirst and urination caused by diabetes,² with overall results comparable to human insulin products³ at a much lower cost.

You Can Do This

Getting a diabetes diagnosis can feel overwhelming, but you are not alone—hundreds of thousands of pets in America are living with diabetes.⁴ You can help keep your diabetic pet healthy by maintaining a set insulin routine, following vet recommendations on diet, activity and play, and bringing your pet in for regular checkups. Call your vet for advice if you’re ever uncertain.


1. Ward CR, Christiansen K, Li J, et al. Field efficacy and safety of protamine zinc recombinant human insulin in 276 dogs with diabetes mellitus. Dom Anim Endocrin. 2021;75. 2. HNelson RW, Henley K, Cole C, et al. Field safety and efficacy of protamine zinc recombinant human insulin for treatment of diabetes mellitus in cats. J Vet Intern Med. 2009;23:787-793. 3.Gostelow R, Scudder C, et al. One-year prospective randomized trial comparing efficacy of glargine and protamine zinc insulin in diabetic cats. Abstract format. ACVIM Forum 2017. 4.State of Pet Health Report. Banfield Pet Hospital website. Accessed October 27, 2020.

Important Safety Information

PROZINC is for use in dogs and cats only. Keep out of the reach of children. Owners should be advised to observe for signs of hypoglycemia (low blood sugar). Signs may include weakness, depression, behavioral changes, muscle twitching, and anxiety. In severe cases of hypoglycemia, seizures and coma can occur. Hypoglycemia can be fatal if an affected animal does not receive prompt treatment. PROZINC should not be used during episodes of hypoglycemia (low blood sugar). Appropriate veterinary monitoring of blood glucose, adjustment of insulin dose and regimen as needed, and stabilization of diet and activity help minimize the risk of hypoglycemic episodes. The attending veterinarian should evaluate other adverse reactions on a case-by-case basis to determine if an adjustment in therapy is appropriate, or if alternative therapy should be considered. The safety and effectiveness of PROZINC in puppies, kittens, or breeding, pregnant, and lactating animals has not been evaluated. For more information.
See full prescribing information


PROZINC is an FDA-approved insulin created for veterinary use in the treatment of diabetes. PROZINC comes from Boehringer Ingelheim, the same company that manufactures HEARTGARD Plus (ivermectin/pyrantel), NexGard (afoxolaner) and FRONTLINE Brand products, plus other leading animal vaccines and medicines. They offer a number of helpful resources for people caring for diabetic pets, including educational and administration videos, treatment diaries and more.

ReviewsWrite a Review

Rated 4.7928 out of 5 stars
222 Ratings
Would recommend to a friend

220 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.
Rated 4 out of 5 stars
By Mdb007 on Aug 27, 2023

Great price and product

One of our cats was diagnosed with diabetes this year and we began giving him insulin shots. The vet price was $80 higher than chewy! Now it did take a couple of days for them to verify the script with vet and after that the insulin came with two day shipping. It was packed in ice packs during a heat wave and was well protected in a large box. My only negative comment was they didn’t email to say script was confirmed and shipment would be going out.

Rated 5 out of 5 stars
By bean on Aug 2, 2023

Major savings

My cat is a high dose diabetic who takes 9 units 2x day to stay regulated. I was previously buying her Prozinc from the vet who charges $140 for a 10ml vial. Insulin must be refrigerated, so I was hesitate to order from Chewy, but based on their generous return policy, I decided to take a chance. My 20ml vial arrived quickly in a refrigerated box full of ice packs, and it was tightly protected so it didn't have much room to shake around. At first I was concerned because the liquid was full of bubbles, but they disappeared after sitting in the fridge. The insulin is as effective as expected, so I'm happy with the purchase. I will continue to buy her insulin and all other diabetic supplies from Chewy. The savings have been huge!

Rated 5 out of 5 stars
By Carolo on Sep 5, 2023

I have been bragging about Chewy ever since you sent insulin: You packed in so it stayed cold until it reached here with such care that I felt my Misty was the most important customer. I feel very secure knowi will receive anything I order in a timely matter.

Rated 5 out of 5 stars
By Dee on Sep 21, 2023

Thank you

This review is more for the excellent service in getting the insulin and syringes to us so quickly after we found out our cat was diabetic. Thank you so much.

Rated 5 out of 5 stars
By Kitty on Aug 17, 2023

It's unbelievable how much I save by ordering ProZinc from Chewy instead of my vet. It stays cold whole in transit so that I never have to worry. I love Chewy's fast service and customer service. They are the BEST!

Rated 5 out of 5 stars
By gungy on Aug 27, 2023


My spooky was diagnosed with diabetes and the Vet's at Chewey were so very kind and understanding with me. I was told that the insulin Prozinc was indeed a product that you carry and and pleased.

Rated 5 out of 5 stars
By LAURA on Jul 31, 2023

Excellent service

Bought insulin for my cat for the first time from anywhere other than vet. The process was smooth, communicated with me the entire time as far as shipment arrival. When it arrived it was well protected and remained cold.

Rated 5 out of 5 stars
By Connie on Jun 15, 2023

As expected

This is my first time ordering prescription meds from Chewy as my kitty is newly diagnosed. All went smoothly with the order and delivery but I feel the packaging was a bit excessive. I understand insulin needs to be kept cold but the foam container it came in is huge for the tiny bottle. There were 4 ice packs inside that stayed frozen for almost 2 days. Non of this is recyclable.

Rated 1 out of 5 stars
By Jessica on Aug 2, 2023

Insulin arrived at 76 degrees

Arrived today, middle of summer and Insulin was not packed properly so Insulin was HOT thermometer reading 76 degees

Rated 5 out of 5 stars
By Averill on Apr 19, 2023

Better price.

While looking for a better price on my cats insulin I was lucky to find it at Chewy. The ordering was very easy. I did have to wait for the prescription to be approved, but that only took two days. The shipping was fast and great care was used to make sure it was keep cold. Would recommend Chewy to anyone looking for their pet needs.