How to Give Caninsulin Using a U-40 Insulin Syringe

Use the step-by-step instructions below to teach your clients how to administer Caninsulin to their dog from the comfort of their home.

Downloadable Caninsulin Instructions

Important Dosage Information

Doses of insulin are measured in units and insulin products contain a specific number of units for every millilitre of product.

Caninsulin contains 40 International Units (IU) per millilitre (ml); 40IU/ml insulin, whereas human insulin products contain 100IU/ml. Because of this difference, to ensure pets receive the correct prescribed dose, we should only administer Caninsulin with the VetPen or U-40 syringes that are designed to measure out doses of 40IU/ml insulin.

Using anything other than U-40 syringes or the VetPen to deliver Caninsulin will result in incorrect dosing. For example, using a U-100 syringe designed to deliver 100IU/ml insulin, or a human insulin delivery pen with Caninsulin would result in significant underdosing, which could lead to instability and worsening of clinical signs.

Unless they are aware, clients may attempt to replenish their syringe stock and/ or insulin supply from their local pharmacies but most pharmacists are not aware of Caninsulin, VetPen, or the U-40 syringes, nor do they stock these items.

The best way to protect pets from incorrect insulin dosing by this route is to educate pet owners on this difference and encourage them to purchase Caninsulin, U-40 syringes or the VetPen via their veterinary practice.

Preparing the Dose

After washing your hands, shake the vial of Caninsulin (porcine insulin zinc suspension) until it is uniformly milky, allowing any foam to dispense.

Injection Technique

Refer to the Caninsulin Summary of Product Characteristics for more information.

Convenient and Accurate Caninsulin Injections

VetPen from MSD Animal Health is the first and only veterinary insulin pen for use in the treatment of diabetes mellitus in dogs and cats. To avoid dosing errors, VetPen must be used with 40 IU/ ml , 2.7 ml Caninsulin cartridges.

VetPen is available in 2 sizes: 8 IU VetPen with dosing increments of 0.5 IU and 16 IU VetPen with dosing increments of 1 IU. Caninsulin (porcine insulin zinc suspension) 2.7 ml cartridges are available in boxes of 10.

Advise pet owners not to reuse VetPen needles. After a single use, needles should be disposed of in approved sharps or biohazard containers.

How to use Caninsulin VetPen

Watch the video and use the step-by-step instructions below to teach your clients how to use Caninsulin VetPen.

The six simple steps to using VetPen

1. Insert cartridge
2. Attach needle
3. Remove air bubbles*
4. Select dose
5. Inject dose
6. Remove needle

*or priming the cartridge: Only with the first use of cartridge

Step 1: Insert Cartridge

1. Wash your hands
2. Remove the cap and unscrew the body of the VetPen from the cartridge holder
3. Ensure the dose selector arrow points to the start line – if not, press the release button
4. Carefully insert the cartridge into the cartridge holder
5. Screw the cartridge holder onto the body of the VetPen ensuring you are firm but gentle

Step 2: Attach the Needle

1. Carefully remove the paper tab from the outer needle
2. Carefully attach the capped needle onto the end of the VetPen by turning it clockwise until tight          
3. Gently invert the VetPen up and down 10 times – always mix the Caninsulin before each injection to ensure accurate dosing

Step 3: Remove air bubbles - prime the VetPen:

Before the first use, it is important to remove any air from the cartridge (priming) to avoid injecting air and ensure accurate dosing.

1. Prepare VetPen over the sink
2. Holding the VetPen vertically with the needle pointing up, remove the outer caps from the needle
3. Tap the VetPen gently with your finger to push any bubbles to the top
4. Dial one unit on the dose selector by turning the dose selector clockwise
5. Push the release button, ensuring the dose selector is visible
6. Repeat the process until a steady stream of insulin is ejected from the tip of the needle. You may expect to eject as many as six to eight units of air before achieving this
7. Hold the VetPen horizontally and check that the cartridge is free of air bubbles. If not, you need to repeat the above process until the cartridge is bubble free. NOTE: the cartridge contains two small glass beads to assist the mixing of insulin – these are not air bubbles
8. Ensure the arrow on the VetPen points to the start line on the dose selector

Your VetPen is now ready for use.
 

Step 4: Setting the dose

1. Turn the dose selector clockwise until you reach the prescribed dose

NOTE: if your clients have an unsteady hand or poor eyesight, they can use the release button and dose selector adaptors.

Step 5: Giving the Injection:

1. The injection should be given under the skin, around the shoulder blade area with loose skin. Alternate sites with each dose
2. Tent the skin (lift a triangle of skin with your thumb and second and third finger) and insert the needle under the skin horizontally. Keep pressing and continue to hold the injection button firmly with your thumb until the dose selector arrow returns to the start line. Then count slowly to five to ensure the dose is completely administered. You can then remove
3. Advise your client to be sure to make a fuss of their pet, provide positive reinforcement to make the experience a positive one

Step 6: Removing the needle

1. Following the injection, remove the needle by inserting it into the needle remover and unscrewing it
2. Press the blue tip on the needle remover to release, and dispose of, the used needle carefully and safely in the sharps container

Changing the cartridge

Advise your clients to always check the number of units left in the cartridge. If there aren’t enough for the dose, they need to change the cartridge.

1. Ensure the VetPen needle has been removed to prevent accidental injury
2. Unscrew the cartridge holder from the VetPen body and remove the cartridge
3. Rewind the internal plunger by holding the white lower part of the VetPen. Turn the VetPen body clockwise until the internal plunger is fully retracted. NOTE: incorrect re-winding of the internal plunger can result in damage to the VetPen
4. Return to step 1 to load the new cartridge

Refer to the VetPen video for more information.

Is an Adjustment Needed?

Insulin requirements may change suddenly even after a long period of stability because of any of the following concurrent factors:

Vets should re-evaluate dogs with diabetes at appropriate intervals and adjust the dose based on clinical signs, urinalysis and glucose curve results.

Dose adjustments in the dog should be performed in increments of 10%. Following adjustment, wait to re-evaluate until the new dose has been given for a minimum of 3 days (ideally around 7-10 days), unless evidence of hypoglycaemia appears.

Aim to maintain blood glucose concentrations below the renal threshold, between 10-12 mmol/l for the majority of dogs, for a substantial part of the day. This will result in the disappearance of most of the dog's clinical signs, which is the main goal of therapy.

Monitoring and Adjusting Dose

Re-evaluate your canine patients a minimum of 3 days (ideally around 7-10 days) after starting Caninsulin (porcine insulin zinc suspension):

Changing from once to twice-daily therapy

When switching dosage from once-daily to twice-daily, the Caninsulin dose needs to be decreased by 25%. For example, if a dog receives 20 IU of Caninsulin once daily, the new dose would be 15 IU twice daily.

If ideal stabilisation has not been achieved, it is suggested to first investigate the cause of poor regulation: e.g. owner administration issues, insulin storage issues, use of improper syringes, Somogyi overswing, undiagnosed concurrent conditions.

When clinical signs disappear and the owner is happy with the situation, the main goals of therapy have been achieved.

Refer to the Caninsulin Datasheet for further information.

Good glycaemic control is dependent upon a controlled and consistent dietary intake. The dietary requirements of a dog with diabetes is highly variable – the diet must be tailored to each individual dog, ensuring that food offered is palatable and will be readily eaten⁶.

Body weight is a major factor

Obese dogs require reduced caloric intake, either through feeding a calorie-restricted diet or by feeding a reduced quantity of the normal diet. Increasing physical activity will also be beneficial in obese dogs. Conversely, underweight dogs may require calorie-rich diets such as pediatric or convalescent diets.

Timing of meals

Traditionally, the dog’s daily food intake should be divided into two meals. Meals should be timed so that the absorption of glucose from the gastrointestinal tract coincides with peak action of the administered insulin. This will minimise fluctuations in blood glucose concentrations and thus episodes of hyperglycaemia or hypoglycaemia.

It is important for owners to remember that dietary consistency is critical – both the type and amount of food given, as well as feeding times, should be as similar as possible each day.

For once-daily insulin injections

Give the first meal (two-thirds of the daily amount) prior to the morning Caninsulin injection. This allows your client to see that their dog is feeling well and eating normally before the insulin is given.

The second meal (the remainder of the daily amount) is usually given about 8-10 hours later.

For twice-daily injections

The first meal (half of the daily amount) is given just before the morning Caninsulin injection. This allows your client to see that their dog is feeling well and eating normally before the insulin is given.

The second meal (the remainder of the daily amount) is usually given about 10-12 hours later, prior to the second Caninsulin injection.

Presentation of an uncomplicated dog with diabetes

Types of dogs categorised as uncomplicated:

During consultation:

When health status is known, and diabetes mellitus confirmed:

Starting Caninsulin in dogs

Clinically evaluate dosage needed

Determine the owner-preferred method of administration

Caninsulin is available in two presentations, to enable vets and owners to discuss what might be right for them:

Vetpen is the first and only insulin pen to deliver 40 IU/ml insulin via 2.7 ml cartridges. This method is more accurate that the traditional needle and syringe approach and is easy to use^7,8.

Caninsulin is also available in 2.5 ml and 10 ml vials for use with specific 40 IU syringes and needles.

Establish a starting dose

Topics for patient consultation

Discharge dog to owner’s care for one week

This first period allows the dog and owner to become accustomed to the injections and related their concerns and challenges to the clinic team.

At home, ask the owner to:

For cases of poor glycaemic control

Ruling out underlying disorders

Ruling out storage and handling factors

Incorrect storage of insulin or poor injection technique can affect insulin therapy. Ask owners to demonstrate how they inject their pet, and ask the following:

General questions:

If using a syringe:

If using VetPen:
 

See Proper Handling and Storage and delivery of Caninsulin for more information.

Antibodies

Antibodies may be directed either against the insulin or against other foreign proteins in the preparation. The presence of anti-insulin antibodies is common and does not usually lead to poor regulation. Antibody production is less likely if homologous insulin (has the same structure as the recipient) is given, e.g. the porcine insulin (in Caninsulin) has the same structure as canine insulin⁹.

Stabilising diabetes long-term in dogs

Help clients understand that their dogs can live healthy, active lives when their dog’s diabetes is properly regulated.

Monitoring

Once the maintenance dose has been established and the dog is stable, a long-term management program must be implemented. The aim is to minimise variations in insulin requirement. This includes monitoring to detect underdosage or overdosage of insulin, and adjustment of dose, if required. Careful monitoring during maintenance will help limit most of the chronic problems associated with diabetes.

Various approaches to maintenance have been described. The most clinically accepted approach is to ask the owner to monitor and record their dog’s general health (including well-being, thirst and appetite) daily. Urine glucose checking at home should only be used where appropriate, such as when hypoglycaemia is suspected and a negative morning glucose would indicate an insulin overdose¹⁰. Dogs should be checked by a vet every 2 to 4 months (more often if there are problems) for general health (and absence of clinical signs), urine glucose and blood glucose as required and indicated by the general health check and owner diary. Adjustments to the insulin dose must be based on full analysis of clinical data and a series of blood glucose measurements.

Other health factors

The use of progestogens in dogs suffering from diabetes mellitus should be avoided. Ovariohysterectomy should be considered for entire bitches. Stress and irregular exercise must be avoided. Care must be taken with the use of corticosteroids. It is important to establish a strict feeding schedule in consultation with the owner that is consistent and avoids too many fluctuations and changes¹⁰.

Clinical signs to watch for

It is extremely important that owners can recognise the signs of hypo- or hyperglycaemia and respond appropriately. Polyuria, polydipsia, and polyphagia in combination with weight loss, poor condition, loss of hair or hirsutism and lethargy are the most common clinical signs of hyperglycaemia and require administration of insulin to restore blood glucose levels to an acceptable range.

However, these clinical signs may also be present as a result of a rebound hyperglycaemia secondary to a hypoglycaemic episode (Somogyi overswing). While a blood glucose curve can help differentiate between insufficient insulin dosing and Somogyi overswing, the results can be confusing if the rebound hyperglycaemia persists for a few days and may not be associated with the time of insulin administration. Evaluating weight changes in the patient can help shed some light on this issue. If the dog is losing weight and exhibiting clinical signs of diabetes mellitus, the insulin dose may be insufficient. If the dog is gaining weight but continues to have clinical signs consistent with diabetes mellitus, the insulin dose may be excessive, and causing Somogyi overswing.

The signs of hypoglycaemia may occur suddenly and can be life-threatening, so it is important owners are very aware of these and know how to respond. Signs include lethargy or dullness, restlessness and anxiety, weakness and a staggering gait and muscle twitching / shivering. If not treated, these can lead to convulsions, coma and, eventually, can be fatal.