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ProZinc (protamine zinc recombinant human insulin) U-40 Injectable for Dogs & Cats, 10-mL

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$125.11 Autoship Price
(-5%)
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$131.69 Chewy Price
($13.17 /mL)
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Usually arrives in 3-5 days
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This item is specially packaged to remain refrigerated during transit.

About This Item

Details

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.We directly source prescription medications from manufacturers and wholesale distributors registered with the FDA and licensed by applicable state boards. Guaranteed genuine, and where applicable, backed by the manufacturer.

Ingredients

Instructions

FAQ

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.

References:

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. https://www.banfield.com/state-of-pet-health. 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

About PROZINC

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.
Shop PROZINC
4.8
Rated 4.8 out of 5 stars
1948 Ratings

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Ease of Use

92% Positive

Effectiveness

88% Positive

Ingredients

89% Positive

Long-Term Benefits

89% Positive

810 Customer Reviews



Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Tosha on Feb 3, 2026

Customer Service

My first order was delivered to the wrong house to my neighbors while I was gone. I reached out due to the insulin being left out for a long period of time and not

My first order was delivered to the wrong house to my neighbors while I was gone. I reached out due to the insulin being left out for a long period of time and not cold and they promptly got me a replacement shipped asap. Got it today in time for my pets next dose! I’m very pleased with the prompt customer service and help from the staff to make this less worrying for me. Thanks so much!


Rated 5 out of 5 stars
By DogMum on Jan 24, 2026

Easy process

This was my first time ordering this here and I must say I am impressed. It shipped immediately after our vet approved the prescription. It was sent by overnight

This was my first time ordering this here and I must say I am impressed. It shipped immediately after our vet approved the prescription. It was sent by overnight delivery and packed in a nice large insulated box for protection and the ice pack was still frozen and insulin was nice and cold. Expires two years from now. And much more reasonable in price here. Thank you!!!


Rated 1 out of 5 stars
By Natasha on Jan 2, 2026

Delivery Nightmare

We have never had an issue with delivery until now. Only one ice pack and it was NOT delivered overnight. Ice pack was melted by the time it got here. Insulin is

We have never had an issue with delivery until now. Only one ice pack and it was NOT delivered overnight. Ice pack was melted by the time it got here. Insulin is slightly cool, but by no means as cold as it is when refrigerated properly. Not only dissatisfied, but a little concerned for my cat using this medicine.


Rated 5 out of 5 stars
By Susan on Jan 16, 2026

Shows great care for my cat's health!

The pharmacy tech called to tell me about a response given in error by my vet's office. I was able to get it corrected before it negatively affected my cat's health

The pharmacy tech called to tell me about a response given in error by my vet's office. I was able to get it corrected before it negatively affected my cat's health. Chewy's pharmacy is the best!


Rated 5 out of 5 stars
By Joyce on Dec 19, 2025

Customer care

Pharmacist reached out to my vet to get an emergency refill after chatting with them on the chat function. I'm really surprised at how good the follow through was

Pharmacist reached out to my vet to get an emergency refill after chatting with them on the chat function. I'm really surprised at how good the follow through was and how quickly it was done. Very appreciative. Thank you from me and my pet.


Rated 5 out of 5 stars
By Charles on Jan 26, 2026

Price

Our cat Winston is on insulin and over-the-counter products will not work for him. It was very hard to fine this product I'm so thankful you carry it.

Our cat Winston is on insulin and over-the-counter products will not work for him. It was very hard to fine this product I'm so thankful you carry it.


Rated 5 out of 5 stars
By Valentina on Oct 27, 2025

Great experience with chewy

It’s been stressful managing my cat’s diabetes, and this drug has managed it very well. But my review is more so about Chewy and their service. They do such a great

It’s been stressful managing my cat’s diabetes, and this drug has managed it very well. But my review is more so about Chewy and their service. They do such a great job and are so reliable. Their customer service reps are always super helpful. Chewy has made it so easy. They contact the vet on your behalf and everything, I don’t even have to do anything. And the insulin vial comes packaged SO extremely carefully, with a ton of ice packs as well. And it arrives to me very quickly. Chewy is such a trustworthy company, love them!


Rated 5 out of 5 stars
By Chris on Dec 18, 2025

Thanks for caring

I contacted Chewy regarding the passing of Mya. They, without asking, refunded me her most recent bottle of Prozinc 235.00. Then, a few days later, I received flowers

I contacted Chewy regarding the passing of Mya. They, without asking, refunded me her most recent bottle of Prozinc 235.00. Then, a few days later, I received flowers and a sympathy card. Thank You Chewy


Rated 3 out of 5 stars
By Kathleen on Oct 31, 2025

FedEx driver bad

The driver basically threw the box on my front porch and it flipped on its side. If I didn't have FedEx notification and a Yi camera to see it was delivered around

The driver basically threw the box on my front porch and it flipped on its side. If I didn't have FedEx notification and a Yi camera to see it was delivered around 12:15 and went home to refrigerate it,it might not have still been cold at 5:00 when I normally get home because the vial was outside of the cold packs due to the box being flipped. I have a video of the driver if you want it


Rated 5 out of 5 stars
By Nancy on Jan 31, 2026

The staff

The service I received from the staff was amazing. No wonder why they have so much business. Thank u very much.

The service I received from the staff was amazing. No wonder why they have so much business. Thank u very much.