Introduction
Insulin glargine is a long-acting, man-made insulin that is used to control high blood sugar in people and dogs with diabetes mellitus. It works by helping glucose enter the cells where it can be used for energy. Glargine insulin is a basal insulin, meaning it provides background 24-hour blood sugar control.
Insulin glargine is commonly prescribed for diabetic dogs who need long-lasting insulin to maintain normal blood sugar levels. It is usually given once or twice daily by injection. The dose must be adjusted for each dog based on factors like their response to treatment and glucose curve results.
This article provides an overview of using insulin glargine to manage diabetes in dogs. It covers topics like diagnosis guidelines, dosage information, administration instructions, diet and exercise recommendations, monitoring blood sugar, managing side effects, and long-term care.
Diagnosing Diabetes in Dogs
Diabetes mellitus is one of the most common endocrine diseases in dogs. Some of the most common signs and symptoms of diabetes in dogs include:
- Excessive thirst and urination
- Increased appetite but weight loss
- Fatigue
- Cloudy eyes
If diabetes is suspected, veterinarians will run several diagnostic tests to confirm the diagnosis, including:
- Complete blood count (CBC) – evaluates red and white blood cell counts which may indicate infection
- Biochemistry profile – measures glucose, electrolyte and enzyme levels
- Urinalysis – checks for glucose in the urine confirming insufficient insulin
Early diagnosis and treatment for diabetes is critical. Untreated diabetes can lead to serious complications like diabetic ketoacidosis, cataracts, urinary tract infections, and more (Source). Catching diabetes early allows for better regulation with insulin therapy and improved quality of life.
When to Prescribe Glargine Insulin
Veterinarians may prescribe glargine insulin for dogs in certain cases where it offers advantages over other types of insulin:1
- For dogs that require twice-daily insulin injections to control their blood glucose.
- When longer duration of action is desired compared to regular insulin.
- For dogs that have unpredictable variability or erratic spikes in blood glucose with other insulins.
- To minimize the risk of hypoglycemia which can occur with shorter-acting insulins.
- For diabetic dogs that are difficult to regulate on other types of insulin.
- For owners who desire simplicity with twice-daily dosing rather than more frequent injections.
Glargine may be preferred for dogs with frequent hyperglycemic or hypoglycemic episodes on other insulins. Its long, steady action can minimize glucose fluctuations. However, glargine is usually more expensive than other insulins.2
How Glargine Insulin Works
Glargine insulin is a long-acting basal insulin that helps control blood sugar levels throughout the day and night. It works by mimicking the background release of insulin by the pancreas in people without diabetes. It has an altered molecular structure that allows it to form microprecipitates in the subcutaneous tissue after injection, slowing its absorption into the bloodstream.[1]
The main benefits of glargine insulin over other basal insulins like NPH are:[2]
- Prolonged, peakless action lasting approximately 24 hours with a relatively constant concentration/effect.
- Lower risk of hypoglycemia compared to NPH insulin.
- Once daily dosing that provides steady base insulin coverage.
This long, steady action makes glargine a useful basal insulin for managing both type 1 and type 2 diabetes. It can be combined with short-acting insulins like lispro to cover mealtime spikes.[3]
Dosage Guidelines
The recommended starting dose of glargine insulin for dogs is typically 0.3 units/kg (or 0.136 units/lb) injected subcutaneously twice daily. This is based on clinical trials showing effective glycemic control with this initial dosing (1).
For smaller dogs under 10 lbs, an initial dose of 1-2 units twice daily may be suitable. Larger dogs over 100 lbs may need a higher starting dose of 0.5 units/kg twice daily. It’s important to monitor blood glucose levels closely and be prepared to adjust the insulin dose based on how the individual dog responds (2).
Several factors can affect the ideal glargine insulin dose for a dog including underlying health conditions, changes in diet/exercise, concurrent medications, and progression of the diabetes. Frequent veterinary visits and blood glucose curve tests are needed, especially early in treatment, to determine if dose adjustments are necessary. The dose should be lowered if blood glucose drops below normal levels.
The maximum total daily dose of glargine insulin for dogs is generally considered 1 unit/kg. Exceeding this level increases the risks of hypoglycemia. However, refractory cases unresponsive to standard dosing protocols may require higher doses under close veterinary supervision.
For diabetic dogs transitioning from other insulin types (e.g. Vetsulin, ProZinc), the starting dose of glargine may need to be slightly higher than the previous insulin dose. Your veterinarian can provide guidance on appropriate dosing conversions.
Administering Injections
When administering glargine insulin injections to dogs, it’s important to use the proper injection technique and rotate injection sites to maximize absorption and avoid irritation. Some key steps for safe and effective injections include:
Choose an injection site like the neck, shoulder or hindquarters where you can grasp a fold of loose skin. Make sure to rotate sites so you don’t irritate one area. Part the fur to expose the skin.(1)
Use small 30 or 31 gauge, 5/16-1/2 inch needles that are designed for animal injections. Shorter needles work best for cats and small dogs.(2) Make sure the syringe is air bubble-free before injecting.
Pinch up a fold of skin and quickly insert the needle. Push the plunger slowly to administer the dose. Leave the needle in place for 5 seconds before withdrawing to ensure full delivery.(3)
Apply gentle pressure to the injection site for 30 seconds after withdrawing the needle to avoid leakage. Reward with a treat for being cooperative!
Be patient, calm and confident when handling your dog for injections. Proper technique comes with practice – your vet can demonstrate until you’re comfortable administering injections at home.
Monitoring and Adjusting Doses
Frequent blood glucose monitoring is essential when managing a dog on glargine insulin therapy. Blood glucose curves, obtained by testing glucose every 2-4 hours over a 12-24 hour period, provide vital information for assessing insulin efficacy and determining the optimal dosing schedule.
Signs of hypoglycemia, or low blood sugar, include lethargy, unsteady gait, tremors, and seizures. It is imperative to contact the veterinarian immediately if hypoglycemia is suspected, as it can quickly become life-threatening without treatment. Signs of hyperglycemia, or high blood sugar, include increased thirst, increased urination, weight loss, and vomiting. Notify the veterinarian if these signs persist over 2-3 days despite insulin therapy.
The starting dose of glargine insulin for dogs is typically between 0.5-1.0 units/kg every 12 hours. However, the dose always needs adjustment and customization for each patient based on regular monitoring. After analyzing a blood glucose curve, veterinarians may increase or decrease the dose incrementally or change the timing of injections to better control blood sugar.[1] Contact the veterinarian immediately if the current insulin regimen does not appear to be adequately controlling blood glucose levels.
Diet and Exercise
Proper diet and exercise are extremely important for managing diabetes in dogs on glargine insulin. An appropriate diet helps regulate blood glucose levels and facilitates weight loss in overweight diabetic dogs. Exercise also promotes weight loss and glycemic control. Working closely with your veterinarian, you should develop a customized diet and exercise plan for your diabetic dog.
Many vets recommend feeding a high-protein, high-fiber, low-carbohydrate dog food formulated for diabetics. Canned dog foods often have lower carbs than dry kibble. Avoid high glycemic foods like simple sugars or white rice. Feed consistent amounts at the same times daily. Don’t make diet changes without consulting your vet first.
Exercise helps lower insulin requirements and enables better regulation of blood glucose [1]. Aim for daily exercise such as walking or playing. Start slow if your dog is overweight and build up duration and intensity. Low-impact exercise like swimming is ideal. Always monitor for signs of hypoglycemia during and after vigorous exercise.
Work closely with your veterinary team to determine the optimal diet and exercise plan. Consistency is key for managing diabetes effectively. Monitor blood glucose regularly and share results so your vet can adjust the insulin dosage and protocol as needed.
Side Effects and Precautions
The main side effect to watch for with glargine insulin is hypoglycemia or low blood sugar. This occurs if the insulin dose is too high relative to the dog’s needs. Signs of hypoglycemia include lethargy, unsteady gait, tremors, and collapse. It’s critical to monitor blood glucose levels routinely and adjust insulin doses based on veterinary guidance. If hypoglycemia occurs, a source of glucose like corn syrup or honey can help stabilize blood sugar until vet care is accessed. Always have a hypoglycemia emergency kit on hand.
Lipodystrophy is destruction of fatty tissue at injection sites which can affect insulin absorption. Rotating sites is key to prevent this. Telltale signs are hard lumps or depressions under the skin at common injection locations. If they appear, new sites will need to be used.
Some dogs develop antibodies against insulin which can make dosing more difficult. This occurs more often with animal-sourced insulins like Vetsulin. Human synthetic insulins like glargine have a lower immunogenic potential. However, antibody formation can still occur and interfere with glycemic control. Let the vet know if this is suspected.
It’s also important to monitor for other side effects like lethargy after injection or skin reactions at injection sites. Report any concerning or abnormal effects to your veterinarian right away. With careful dosing and monitoring, glargine insulin can be used safely long-term in most dogs with diabetes.
Long-Term Management
Successfully managing diabetes in dogs long-term requires an ongoing partnership between you and your veterinarian. Your vet will want to see your dog regularly to monitor their condition and adjust treatment as needed. Expect appointments every 3-6 months once your dog’s diabetes is stabilized.
At these check-ups, your vet will review your dog’s clinical signs, do lab work to check glucose and fructosamine levels, and make any necessary changes to their insulin dose or diet. Keeping detailed records of your dog’s food intake, insulin doses, glucose readings, and any symptoms will help your vet provide the best care.
Your vet may periodically recommend switching to a different type of insulin as your dog’s needs change over time. For example, some vets start with glargine insulin and later transition to detemir or NPH insulin. Work closely with your vet to find the optimal insulin regimen for long-term control of your dog’s diabetes.
Your role at home is critical as well. Maintaining consistent mealtimes, insulin doses, exercise, and avoiding table scraps is key to keeping your diabetic dog’s blood sugar stable. Your dog depends on you to help them live a happy, healthy life with this chronic disease through attentive, loving care and management.
With an excellent long-term partnership between you and your vet, dogs with diabetes can live for many happy years after their diagnosis. Consistency and vigilance are vital, but it’s very possible for diabetic dogs to have an excellent quality of life.