Diabetes in Pets

Close-up illustration of a syringe needle showing bevel, point and heel.

Injecting insulin at home is done subcutaneously, under the skin, but not into muscle or vein. See also Syringe and Insulin pen.

How to inject subcutaneously[]

It's best to pull up some loose skin into a tent[1][2], then insert the needle firmly, bevel side up[3][4] for comfort[5].


Correct way to give an injection when "tenting" the skin. This makes sure the insulin is injected into the skin flap created by "tenting" it. When the skin "tent" is released, the injected insulin is under it, or subcutaneous.


Wrong way to give a shot: The needle has totally passed through the "tented skin". The insulin, or any other injected drug, will be injected into the air. Note that in this graphic, the injection point is much closer to the "pinch" area holding the "tent" up. In the correct graphic, the injection point is closer to the body.

{C BD has animations with narrations to help you learn how to draw insulin properly[6]. Though we don't recommend combining two insulins in the same syringe. Selecting the style of syringe you use personalizes the demo for your needs. The presentation is very clear and unhurried.

BD also has a slideshow which shows how to inject your dog[7] or cat[8].

Injection tips[]

  • Do NOT wipe the needle with alcohol as it removes the protective coating. The coating makes injection easier and less painful[9].
  • Injecting any insulin at the same site repeatedly over time or blunting a needle with re-use[10] can cause a lipodystrophy: either lipoatrophy[11] or lipohypertrophy. Either makes absorption unreliable. But varying the injection site can cause variability in action profile, too. This page illustrates[12] illustrates the most common areas humans with diabetes inject insulin and explains how absorption differs in various areas of the human body. This is true for ALL insulins. The new shot area needn't be very far from where the last shot was given--the distance of the width of 2 fingers will do fine as a measure[13]. Most of us dealing with pet diabetes vary the side we give the injections in--right side mornings and left side evenings, for example. This is another help in avoiding giving shots in the same areas[14].
  • Many people give insulin shots in the scruff of the pet's neck, which is now considered to be a less than optimum choice. The neck area provides poor insulin Absorption, due to it not having many capillaries, veins. etc. (vascularization). Other sites suggested by Dr. Greco include the flank and armpit[15]. Intervet recommends giving injections from just back of the shoulder blades to just in front of the hipbone on either side, from 1 to 2 inches from the middle of the back[16].
  • To eliminate bubbles: If drawing insulin from a vial, set the syringe plunger to the dosage you want to draw, put the needle into the top of the vial while the vial is still upright, and push all the air out of the syringe. This will maintain air pressure equilibrium in the vial once you draw the dose and, because the vial is upright, will not cause air bubbles to mix with the solution. Turn the vial upside down and draw the insulin slowly.
  • If you do get air bubbles into the syringe, it's ok with most insulins to re-inject the insulin into the vial and draw again until the air is gone[17]. Check that this is ok with your insulin. See also injecting insulin. Slower draw is less likely to draw bubbles.
  • Another way to get rid of syringe air bubbles is to hold the syringe upright and give it a tap or two with your finger. The problem with having air bubbles in the injection is that you will not be getting the full dose of insulin; the bubbles take the place of it[18].
  • Some people prefer to gently jiggle their vials to make any air bubbles rise to the top, away from where the needle will draw[19].

Insulin tips[]

Cold insulin[]

Insulin[20] can sting, regardless of what species, type or brand. Bringing the insulin to room temperature by removing it from the fridge before actually using it can help avoid painful injections. Warming the capped insulin syringe with your hands can have the same effect[21]. Some people tuck the capped and filled syringe under their arm for a few minutes to warm it before use. Do NOT attempt to warm insulin using a stove, microwave, etc.; you may destroy the insulin by doing so[22].

Do not use the insulin if[]

Before each use, take a moment to inspect the insulin prior to drawing it into the syringe; clear insulins should appear not discolored and clear; suspended insulins should be uniform in their cloudiness[23].

Do not use the insulin if:

  • Clear insulin that looks discolored or has turned cloudy, or any containing particles or haze[29].
  • Cloudy insulin that appears yellowish or remains lumpy or clotted after mixing[30][31].

Injection problems[]

There are sometimes leakage problems, when some insulin is lost when the needle is removed from the skin[32]. Some possible reasons and "fixes" for this are holding the "pinch" or "squeeze" too long which you made to give the shot.

The skin, now with insulin under it, is still being "squeezed" as it was before the insulin went under the skin. The "pinch" forces some of the insulin back out from the newly-created hole in the skin.

Releasing the "squeeze" or "pinch" first, then counting to 10 before removing the needle from the skin may give the insulin time to penetrate the fat layer and prevent leakage. Short needles can also cause insulin leakage--switching to longer ones can also help.

See also diluting insulin, fine doses, combining insulin, rolling insulin, syringes and insulin pens.

Further Reading[]

Cats - Pictorials[]

Cats - Online videos[]

Dogs - Pictorials[]

Dogs - Online Videos[]

Dogs - Injection Time Tips[]


Injection Site Rotation[]

Online Videos[]


  1. Tenting as shown with Simon
  2. Tenting shown on a hairless cat for clarity
  3. Sarasota Memorial Hospital Subcutaneous Injection Page 4
  4. FDMB discussion on injection technique
  5. Cornell University Feline Health Center:How to Give an Insulin Injection Flash Movie
  6. BD Diabetes-Drawing Insulin Animation with Narration
  7. BD Diabetes Slideshow-Injecting a Dog
  8. BD Diabetes Slideshow-Injecting a Cat
  9. PetDiabetes.org-Tips for Comfortable Injections
  10. Insulin-Dependent Diabetes-Dr. Ragnar Hanas-Page 21
  11. Lipoatrophy can Happen With Any Subcutaneous Insulin-Endocrine Abstracts-2006
  12. Common Human Insulin Injection Areas & Their Absorption Rates
  13. Joslyn Diabetes Center-Tips for Injecting Insulin
  14. BD Diabetes-FAQ's About Diabetic Dogs-Dr. Greco
  15. Better Medicine E-Newsletter-June 2006
  16. Vetsulin-Preparing Insulin & Giving Injection-Page 2
  17. Injecting Insulin-Transcript of American Diabetes Association Videotape-2003
  18. American Diabetes Association 2002 Position Statement-Insulin Administration
  19. Diabetes Self-Management-Injecting Insulin 101
  20. Injecting Cold Insulin
  21. PetTalk.com-Tips and Tricks from Pet Owners
  22. FAQs.org-Travelling With Insulin
  23. RxEd.org-Insulin Therapy-Stability & Storage
  24. Flocculation & Loss of Potency of Human NPH Insulin-Diabetes /Care-ADA-1988
  25. Flocculation of NPH Insulin-Revista Clinica Espanola-(English Translation)-1994
  26. Frosting Caused in NPH/Isophane Insulin By Heat/Cold-Journal-Diabetes.org-1998
  27. Dorlands Medical Dictionary-Definition of Flocculation
  28. ADA-Diabetes Forecast, 2006-Storage & Safety-Frosting of NPH, Lente, Ultralente Insulins-Page 5
  29. Diabetesnet.com-Humalog & Heat
  30. Injection Insulin-Transcript of American Diabetes Association Videotape-2003
  31. ADA-Diabetes Forecast, 2006-Storage & Safety-Particles or Clumps in NPH, Lente, Ultralente Insulins-Page 5
  32. Insulin Leaking From Injection Site