This information is not meant to be a substitute for veterinary care.
Always follow the instructions provided by your veterinarian.
Diabetes mellitus occurs when the pancreas doesn't produce enough
insulin. Insulin is required for the body to efficiently use sugars, fats
Diabetes most commonly occurs in middle age to older dogs and cats, but
occasionally occurs in young animals. When diabetes occurs in young animals,
it is often genetic and may occur in related animals. Diabetes mellitus
occurs more commonly in female dogs and in male cats.
Certain conditions predispose a dog or cat to developing diabetes.
Animals that are overweight or those with inflammation of the pancreas are
predisposed to developing diabetes. Some drugs can interfere with insulin,
leading to diabetes. Glucocorticoids, which are cortisone-type drugs, and
hormones used for heat control are drugs that are most likely to cause
diabetes. These are commonly used drugs and only a small percentage of
animals receiving these drugs develop diabetes after long term use.
The body needs insulin to use sugar, fat and protein from the diet for
energy. Without insulin, sugar accumulates in the blood and spills into the
urine. Sugar in the urine causes the pet to pass large amounts of urine and
to drink lots of water. Levels of sugar in the brain control appetite.
Without insulin, the brain becomes sugar deprived and the animal is
constantly hungry, yet they may lose weight due to improper use of nutrients
from the diet. Untreated diabetic pets are more likely to develop infections
and commonly get bladder, kidney, or skin infections. Diabetic dogs, and
rarely cats, can develop cataracts in the eyes. Cataracts are caused by the
accumulation of water in the lens and can lead to blindness. Fat accumulates
in the liver of animals with diabetes. Less common signs of diabetes are
weakness or abnormal gait due to nerve or muscle dysfunction. There are two
major forms of diabetes in the dog and cat: 1) uncomplicated diabetes and 2)
diabetes with ketoacidosis. Pets with uncomplicated diabetes may have the
signs just described but are not extremely ill. Diabetic pets with
ketoacidosis are very ill and may be vomiting and depressed.
of diabetes is made by finding a large increase in blood sugar and a large
amount of sugar in the urine. Animals, especially cats, stressed by having a
blood sample drawn, can have a temporary increase in blood sugar, but there
is no sugar in the urine. A blood screen of other organs is obtained to
look for changes in the liver, kidney and pancreas. A urine sample may be
cultured to look for infection of the kidneys or bladder. Diabetic patients
with ketoacidosis may have an elevation of waste products that are normally
removed by the kidneys.
The treatment is different for patients with
uncomplicated diabetes and those with ketoacidosis. Ketoacidotic diabetics
are treated with intravenous fluids and rapid acting insulin. This
treatment is continued until the pet is no longer vomiting and is eating,
then the treatment is the same as for uncomplicated diabetes.
the inset picture shows the top of the insulin bottle
Diabetes is managed long term by the injection of insulin by
the owner once or twice a day. Some diabetic cats can be treated
with oral medications instead of insulin injections, but the
oral medications are rarely effective in the dog. There are
three general types of insulin used in dogs and cats:
- short- acting insulin (regular or crystalline) is used
in sick diabetic animals until they are eating again
- NPH and Lente are intermediate- acting insulins
- Ultralente and PZI are long- acting insulins
Insulin comes from different sources including beef or pork pancreas and a
human genetically engineered form called Humulin
availability of animal-source insulins continues to decline.
cats and small dogs need insulin injections more frequently, usually twice
daily, compared to large breed dogs that may only require one dose of
insulin daily. The action of insulin varies in each individual and some
large dogs will need 2 insulin shots daily. The insulin needs of the
individual animal are determined by collecting small amounts of blood for
glucose (sugar) levels every 1-2 hours for 12-24 hours. This is called an
insulin-glucose-response curve. When insulin treatment is first begun, it
is often necessary to perform several insulin-glucose-response curves to
- which insulin type to use
- how much insulin to give
- how often to give insulin
- when is the best time to feed the animal
The animal's insulin needs may change over time requiring a change in
insulin type or frequency of injection. Insulin- glucose- response curves
are usually performed several days after a change in insulin is made.
Before you give insulin injections to your pet, your veterinarian will
show you how to:
- handle insulin
- use a syringe
- draw insulin from the bottle in the correct amount
- give your pet the insulin shot
Insulin is fragile and will become less effective or even inactive, if it
gets too hot or cold, or is shaken vigorously. Pay attention to the
expiration date on the bottle. Discard insulin that is outdated.
You may be able to practice using water and giving the "shot" to an
object such as a piece of fruit until you are comfortable using needles,
syringes and drawing accurate amounts of fluid into a syringe.
Not all syringes used to inject insulin are alike. When you
buy additional supplies, make sure that you buy the right kind
of syringes. Insulin needles are very thin to reduce discomfort
Insulin syringes can fill to hold:
- 30 units
- 50 units
- 100 units
||The syringe is packaged in sterile
paper or plastic wrapping or in a plastic case. The needle is
covered with a plastic cap to keep it sterile. Use a new
syringe-needle combination for each injection.
Insulin syringes have the needle attached. The needle is covered
with a plastic cap to prevent the needle from puncturing the
wrapping and to keep the needle from bending or breaking.
Remove the syringe and needle from the outer wrapping. Do not
remove the needle cap until you are ready to draw insulin into the
||The plunger fits inside the hollow
barrel of the syringe and is pulled part way out of the barrel
to draw insulin into the syringe. The plunger is pushed into the
barrel of the syringe to push insulin through the needle. The
finger grip makes it easier to hold the syringe.
100 unit syringes are numbered by 10's; 10, 20, 30, etc.
The smallest lines between the numbers on a 100 unit syringe,
measure 2 units of insulin.
30 unit syringes are numbered by 5's; 5, 10 , 15, etc.
The smallest lines between the numbers on a 30 unit syringe,
measure 1 unit of insulin.
||The position of the TOP of
the black rubber stopper on the plunger is used to measure the
volume of insulin in the syringe. The TOP of the
black rubber stopper is the part closest to the needle.
||Before each injection,
The insulin bottle should not be shaken but rather gently
rolled between your hands to mix the insulin in the bottle.
||Remove the plastic cap from the
Hold the syringe between the thumb and index finger.
Pull back on the plunger to the desired dose level drawing
some air into the syringe.
You can either pull back the plunger using the middle finger
of the hand holding the syringe or...
Hold the syringe in your left hand between the thumb and index
finger and use the thumb and index finger of the other hand to
pull the plunger or...
Place your index finger against the finger grip and pull the
plunger with your thumb and middle fingers.
||Hold the insulin bottle upside
down in your left hand if you are right handed (opposite for
Place the needle in the center of the rubber stopper. If the
needle is not centered you may be trying to force the needle
through the metal ring that is holding the rubber stopper in
place and will break the needle.
||Use your thumb to push the plunger
and inject the air into the bottle.
The air is placed in the bottle so a vacuum does not form in
the bottle which makes it more difficult to draw insulin from
Insert the entire length of the needle into the insulin
bottle as long as the tip of the needle is in the fluid in the
bottle. Insulin needles are very thin and easily bent. You are
less likely to bend the needle while drawing insulin into the
syringe, if the needle is inserted all the way into the bottle.
If there is only a small amount of insulin left in the
bottle, you may only be able to insert the needle into the
bottle part way or else you will pass through the fluid and into
the air in the bottle.
Draw back on the plunger to the correct dose using your
middle finger to pull back the plunger.
||If it is difficult for you to pull
the plunger with your middle finger, you can use the thumb and
index finger to pull the plunger. So that you do not pull the
needle out of the bottle, curl the three fingers of your right
hand that are not holding the bottle around the syringe trapping
it against your palm. Then pull the plunger with the thumb and
index finger. Your fingers may be covering the numbers on the
syringe so draw more than you need, then push the extra back
into the bottle, until the correct amount remains in the
...or place your index finger against the finger grip to keep
the needle from pulling out of the bottle and pull the plunger
with your thumb and middle fingers.
||If there is an air bubble in the
syringe, draw a little more insulin than the correct dose.
Remove the syringe and needle from the insulin bottle.
Holding the syringe with the needle pointed up, gently "flick"
the syringe to get the air to rise to the top.
||Press the plunger with your thumb
to push the air out of the syringe, until the correct amount of
insulin remains in the syringe.
||This 30 unit syringe has been
filled to 14.5 units.
There is 1 unit between each back line on this smaller syringe.
Smaller syringes allow for more accurate measurements of small
amounts of insulin. The top of the black rubber stopper is half
way between 14 and 15 units.
This 100 unit syringe has been filled to 48 units. There are 2
units between each black line on the barrel. The volume is
measured at the
TOP of the black rubber stopper on the plunger.
Pinch up a fold of skin anywhere along the neck or back using
your left hand if you are right-handed. Use your right hand to
place the needle into the skin fold along the long axis of the
Usually the skin is not cleansed before inserting the needle. If
the cat has a normal immune system, the few bacteria that are pushed under
the skin with the needle will be killed by the cat's immune system.
You can use alcohol on a cotton ball to make the hair lay flat so it is
easier to see where the hair ends and the skin starts. Alcohol takes about
30 minutes before bacteria are killed, so just swiping the hair with alcohol
is not effective in killing bacteria.
||If you place the needle in the
opposite direction, across the skin fold, it is more likely that
the needle will go through one fold of skin and out the other
fold of skin, or may poke into your finger.
Pull back the plunger. If you get air, you placed the needle
through both folds of skin. Remove the needle and try again. If
you get blood, the tip of the needle is in a blood vessel.
Remove the needle and try again.
If you get neither air nor blood, the needle is placed
correctly and you can push the plunger to inject the insulin.
Give the insulin shots in different locations each time.
Syringes and needles used to give insulin should not be discarded in the
trash but should be placed in a puncture-proof container and taken to your
veterinarian for disposal.
Insulin injections are not as perfect as the insulin produced by the
pancreas. Blood sugar levels will not always be normal in diabetic pets. The
goal of treatment is to reduce the signs of diabetes. When diabetes is well
controlled with insulin, the pet should drink, eat and urinate normal
amounts. They should have a good appetite, without becoming fat and should
have normal activity.
Insulin needs are closely related to the type of
food eaten by the pet. Your veterinarian will recommend a specific diet and
feeding regimen that will enhance the effectiveness of insulin. If your pet
is overweight, s(he) will be placed on a weight-reducing diet. As the pet
loses weight, less insulin will be needed. Only feed the recommended
diet..NO table scraps or treats that are not part of the recommended diet.
Heavy exercise will reduce the amount of insulin needed. It is important
to talk to your veterinarian before making changes in diet or exercise.
There is always some risk that a diabetic patient will develop low blood
sugar. Signs of low blood sugar include weakness, staggering, seizures, or
just being more quiet than usual. You should keep corn syrup on hand to rub
on the animals gums if they have signs suggestive of low blood sugar. Don't
pour large amounts of corn syrup in the mouth of an animal that is not fully
conscious as the syrup may be inhaled into the lungs.
Because insulin needs vary with the activity and lifestyle of your pet,
you may want to keep a written daily log of:
- the dose of insulin
- location in which the insulin is injected
- any changes in the pet’s activity or appetite
Your veterinarian may ask you to check your pet's urine for sugar using a
test strip. If your pet is well regulated on insulin, the sugar readings in
most urine samples will be negative or trace. The strips may have color pads
only for glucose or for glucose and ketones.
The strip is placed in fresh urine and the color change compared with the
colors on the bottle. Be sure to follow the label instructions for timing
when to read the results.
||The top color pad is to read urine
sugar. This sample is negative for sugar. The bottom color pad
is for ketones and is also negative for ketones.
||The glucose pad has turned brown
indicating a large amount (>2000mg/dl) of sugar in the urine.
The urine is negative for ketones.
You should never change the dose of insulin based on the urine
sugar reading alone. Animals can have lots of sugar in their urine either
when the insulin dose is too low or is too high.
||If your pet is difficult to
regulate with the proper dose of insulin you may be taught how
to take a small blood sample from your pet to measure blood
sugar readings at home.
There are many styles of machines used to measure blood
sugar. The machines are called glucometers. They use color
sticks which are read by the glucometer rather than by color
changes you can see. Different styles of glucometers use
different color strips.
Diabetes is rarely reversible in dogs, but diabetic cats will sometimes
regain the ability to produce their own insulin in the pancreas. Cats that
developed diabetes after receiving long term glucocorticoids or hormones are
more likely to stop needing insulin after a while compared to cats that
developed diabetes without a known cause.
You should have your diabetic pet evaluated by a veterinarian at 2-4
month intervals or anytime another health problem develops. The development
of other health problems will often interfere with insulin regulation.
Washington State University assumes no liability for injury to you or
your pet incurred by following these descriptions or procedures.
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