%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B){kind=small}
%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B){kind=small}
What issues might be encountered when switching insulin?
Caution should be exercised when changing from one insulin product to another. Any change in insulin should be made cautiously and only under a veterinarian's supervision. Changes in insulin strength, manufacturer, type, species (animal, human) or method of manufacture (rDNA versus animal-source insulin) may result in the need for a change in dosage.
What is the approach if the insulin appears to have become ineffective?
Most apparent problems with insulin administration are simple. It is important to check if:
If there are signs of poor glycaemic control but the blood glucose nadir is between 5 mmol/l (90 mg/dl) and 10-12 mmol/l (180-216 mg/dl) then there may be either:
1. an administration or storage problem. Read more...
2. insulin resistance. Read more...
Administration and storage problems
1. Dose too high: if the blood glucose nadir is less than 5 mmol/l (90 mg/dl) or blood glucose concentrations fall rapidly, there can be a rebound hyperglycemia (Somogyi phenomenon). The blood glucose nadir should be in the correct range. A serial blood glucose curve with samples every 2 hours must be constructed to clarify this. A single blood sample at the time the blood glucose nadir is expected is not sufficient.
2. Owners technique: It is important to observe the pet owner's technique, particularly when an animal has been well controlled for some time! Watch out for:
What is insulin resistance?
This should be suspected if the insulin requirements increase to more than 1.2 units per kg once daily in the dog, or more than 1.2 units per kg twice daily in the cat and particularly if requirements are greater than 2 units per kg! Obvious causes of insulin resistance include obesity but after initial stabilization these should not result in a dramatic increase in insulin dose requirements.
Remember that some dogs require insulin twice daily. In these animals an increase in dose may not produce an increase in duration of action but precipitate hypoglycaemia and responsive hyperglycemia. If the duration of insulin action is less than 10-12 hours in a dog then it should receive insulin twice daily.
Read more about Rapid insulin metabolism
Read more about Insulin resistance
What is Vetsulin?
Vetsulin (porcine insulin zinc suspension) is the name of Caninsulin in the USA. Vetsulin is the first and only insulin approved by the US Food and Drug Administration for treating both canine and feline diabetes mellitus. Vetsulin and Caninsulin are produced by MSD Animal Health and are available only on prescription.
What type of insulin is Caninsulin?
Caninsulin is an intermediate-acting, lente insulin containing 40 IU per mL of highly purified porcine insulin. As a lente insulin, Caninsulin is an aqueous suspension containing 30% amorphous and 70% crystalline zinc crystals in a neutral buffer of pH 7.35.
How long can the Caninsulin vial be kept after opening?
Caninsulin should be stored in a refrigerator and not frozen. It is usually advised that any pharmaceutical product should be disposed of around one month after opening. The Caninsulin label stated that the product should be used for either 28 days or 42 days after first opening, depending on the country. This is based on studies that were carried out looked at Caninsulin use for up to 42 days after first opening. Most of the authorities that regulate medicines do not allow product labels that permit the use of sterile products for more than 28 days after first opening, hence the discrepancy between countries.
Can Caninsulin be pre-loaded into syringes?
Caninsulin can be preloaded into syringes for clients. However, this will be off label use since it is outside the primary packaging (a glass vial). In addition, it may be difficult to re-suspend small volumes of insulin in a syringe.
What should Caninsulin look like?
Caninsulin is a mixture of two different types of insulin. Normally, after gentle mixing (invert (upend) the bottle several times), Caninsulin will appear uniformly clear to slightly cloudy and should not have lumps or flakes floating in it. If you see clumps or flakes floating in the vial after you have re-suspended the product, do not use it.
A small white ring of sediment may be seen in the neck of some vials of Caninsulin. The ring of sediment forms when the product has not been kept stored continuously in an upright position. A small ring of dried out insulin does not affect the quality of the product. Caninsulin should be stored refrigerated and in an upright position.
Always check on the appearance of the Caninsulin before using it!
Can Caninsulin be diluted?
Caninsulin is a mixture of amorphous (soluble) insulin and crystalline insulin. The crystalline part is relatively insoluble which is why the insulin activity lasts more than a few hours. Caninsulin has a balance between the amorphous and crystalline parts. If Caninsulin is diluted, this could result in an alteration of the pharmacokinetics. In addition, the stability of the new suspension is unknown.
Are there some guidelines for converting an animal from another insulin?
When an insulin change is necessary, one must be very cautious. Due to the nature of the disease, it is difficult to have general guidelines; however, some recommendations can be made:
Important: It is important to check that the new dose does not produce hypoglycaemia. This can be done after the first dose is given around the time that the blood glucose nadir is expected. The animal should then be rechecked 5-7 days later and the dose adjusted further if required.
Dogs - an increase in insulin dose will vary according to the size of the dog. For example, a small dog receiving 2 IU will have its dose increased by increments of 1 IU per injection. For a larger dog receiving a starting dose of 25 IU, increments of 3-5 IU per injection can be used. For more information see dose adjustment in dogs.
Cats - increments of 1 IU per injection are recommended. For more information see dose adjustment in cats.
Monitoring after conversion.
In all cases where the insulin dosage (type, dose or administration frequency) has been changed, close monitoring of the animal is necessary.
Regulation is not always easy. The human factor can be a major source of problems. A new product at a different concentration, new syringe, and/or new treatment schedule can be confusing, especially for the pet owner. Follow-up visits are highly recommended. For more information see Monitoring.
Important: In all cases, one should allow the animal to adapt to each new dose. At least one week or even longer is recommended. Larger or more frequent increases in dose are not recommended due to individual variation in insulin responsiveness.
What is the starting dose of Caninsulin for dogs?
Many specialists recommend twice daily Caninsulin in dogs at a maximum of around 0.5 IU/kg per dose. The current label dose of Caninsulin (in most countries) is 1 IU/kg plus a body weight related supplement. In the US, Caninsulin (under the trade name Vetsulin) now has a starting dose of 0.5 IU/kg once daily, with the recommendation to change to twice daily dosing if required.
It is expected that around two-thirds of dogs will require twice daily dosing. In other words, around one-third of diabetic dogs are managed well on once daily treatment with Caninsulin. The decision to use once or twice daily Caninsulin must be made on an individual case basis.
What is potential diabetes mellitus and when does it occur?
Remission should not be confused with potential diabetes mellitus seen in female dogs during metestrus (diestrus), in which the pancreatic islets are still able to function but signs of diabetes appear as a result of insulin resistance caused by progesterone-induced production of growth hormone by the mammary gland. These dogs are not truly diabetic but can become so if not treated appropriately (ovariohysterectomy/ovariectomy).
What is diabetic remission and when does it occur?
Diabetic clinical remission is a complete or partial disappearance of the clinical signs of diabetes in response to insulin treatment.
An intact female dog presented with clinical signs of diabetes mellitus should be spayed (ovariohysterectomy/ovariectomy) as soon as possible. These animals may require insulin treatment but the diabetes mellitus may be transient.
What results typically can be expected from Caninsulin therapy in dogs?
Diabetic dogs in clinical trials responded to porcine insulin zinc suspension in the following ways:
In most dogs, Caninsulin will produce adequate blood glucose control, with less than one-third having hypoglycemic episodes.
How does Caninsulin work in dogs?
A lente (intermediate-acting) form of insulin, Caninsulin contains 30 percent amorphous insulin for rapid onset of activity, usually peaking about 4 hours after injection and lasting 8 hours. The remaining 70 percent of the formula is crystalline insulin which is absorbed more slowly and peaks around 11 hours after administration. This formulation allows for a more continuous utilization of glucose to support the body's basic functions. Caninsulin is administered subcutaneously once a day initially, although many dogs require twice-a-day administration for effective diabetes management.
Can Caninsulin really be used only once-a-day in dogs?
Clinical studies have demonstrated that approximately one-third of diabetic dogs can be maintained adequately on once-daily doses of Vetsulin. The other two-thirds of dogs will require twice-daily administration of Caninsulin.
How often does Caninsulin need to be administered to dogs?
Initially, the dose should be given once daily concurrently with or right after a meal. The veterinarian should reevaluate the dog at appropriate intervals and adjust the dose in 10% increments based on clinical signs, urinalysis results, and glucose curve/spot check values until adequate glycemic control has been attained. Twice-daily therapy should be initiated if the duration of insulin action is determined to be inadequate. If twice-daily treatment is initiated, each of the two doses should be 25% less than the once-daily dose required to attain an acceptable nadir.
The impact on blood glucose peaks may last from 14 to 24 hours, and approximately one in three diabetic dogs can achieve successful diabetes management with a single dose of Caninsulin per day. The treating veterinarian would need to determine the frequency of a patient's dose.
How many dogs currently have diabetes?
It is estimated that roughly 1 in 500 dogs suffers from the signs of diabetes mellitus.
Is hind limb paresis a typical sign of diabetes mellitus in cats?
Hind limb paresis may be the result of feline diabetes.
Hind limb paresis is also seen in a number of other conditions in cats:
How many cats currently have diabetes?
Estimates of the incidence of diabetes mellitus in cats range from 1 in 100 to 1 in 500.
How does Caninsulin work in cats?
A lente (intermediate-acting) form of insulin, Caninsulin contains 30 percent amorphous insulin for rapid onset of activity. The remaining 70 percent of the formula is crystalline insulin which is absorbed more slowly. This formulation allows for a more continuous utilization of glucose to support the body's basic functions. In cats, the peak activity following subcutaneous administration of Caninsulin occurs between 1.5 and 8 hours (with an average of about 4 hours), and a duration of activity varies between 8 and 12 hours. Caninsulin is administered subcutaneously twice a day in diabetic cats.
What is diabetic clinical remission and when does it occur?
Diabetic clinical remission is a complete or partial disappearance of the clinical signs of diabetes in response to insulin treatment. This is seen not infrequently in diabetic cats with remission rates of at least 25% and 65% or more when diabetic diets are fed in addition to insulin treatment.
What results typically can be expected from Caninsulin therapy in cats?
Cats are usually started on 1 to 2 IU of Caninsulin per injection twice daily. Glycemic control is evaluated based on clinical signs and blood glucose curves, supported by other laboratory results, such as fructosamine. Adjustment of the Caninsulin dose is made according to clinical improvement, average blood glucose concentrations, and blood glucose curve nadirs. Treated cats have significantly lower blood glucose levels and a reduction in hyperglycemia-associated clinical signs compared with pretreatment levels. Diabetic remission is also observed.
How often does Caninsulin need to be administered to cats?
In cats, the initial recommended dose is 1 to 2 IU per injection, and the injections should be given twice-daily (BID) at 12-hour intervals. Initial dosing is based on a per animal basis. The duration of activity of Caninsulin in the cat is shorter than in the dog, ranging between 8 to 12 hours. Peak activity level occurs between 1.5 to 8 (average of about 4) hours in the cat.
Is there information about the use of Caninsulin in rabbits?
Caninsulin is not registered for use in rabbits.
The following information is provided by Dr. Thomas Göbel (Kleintierpraxis, Mecklenburgische Straße 27 14197 Berlin.)
Background Information
Diabetes mellitus in rabbits resembles insulin-independent diabetes in humans. Whether insulin secretion is limited, maintained or elevated, tissue sensitivity to insulin is decreased (peripheral insulin resistance), resulting in a relative insulin deficit. The characteristic clinical signs are polydipsia, polyuria as well as polyphagia and weight loss. Occasionally, uni- or bilateral cataracts are observed. There is also glucosuria.
The diagnosis is made based on the history, clinical signs and blood sugar concentrations measuring repeatedly above 300 mg/dl (16.7 mmol/l).
Dosage
The dosage of Caninsulin that is administered to a diabetic rabbit should be based on the level of control of blood glucose concentrations. An initial dose of 1 unit per kg once daily is recommended. On the basis of the efficacy, a higher dose (up to 3 units/kg once daily) or two doses per day can be given. Please take note that higher doses should not be administered for at least 2 days because a clear reaction to the insulin treatment is usually observed only after this amount of time. A higher dose given too soon might cause sudden clinical signs: polyuria, polydipsia and polyphagia, as well as the return to normal of the rabbit. The desired blood sugar concentration is between 120 and 250 mg/dl (6.7 and 13.9 mmol/l). Lower levels increase the danger of hypoglycaemic episodes.
Feeding
The food of rabbits is naturally full of crude fiber; rabbits eat small portions throughout the day. The food of a diabetic rabbit must consist of hay, high quality green forage and little ready-made food. Ready-made food is often very energy rich and contains too little crude fiber. Feeding diabetic rabbits tidbits and sweet fruit (e.g. apple, pear and berries) is not advised.
Control
Rabbits that are doing well on insulin treatment should be checked every three months. The blood and urine glucose concentrations should be measured. It is also normal to check the rabbit’s general well being and its diet.
References
Ewringmann A, Göbel T (1998) Diabetes mellitus bei Kaninchen, Meerschweinchen und Chinchilla. Kleintierpraxis 43, 337-348.
Ewringmann A & Göbel T (1998) Untersuchung blutchemischer Parameter bei Heimtierkaninchen. Kleintierpraxis 43, 447-452.