Diabetes Mellitus (DM) can affect dogs and cats alike, and is a disorder that occurs when your pet is unable to regulate its blood sugar (glucose) levels. An organ called the pancreas produces a hormone called insulin that is secreted into the blood and helps regulate blood glucose levels. Diabetes mellitus occurs when the pancreas does not produce any insulin, does not produce enough insulin, or the body does not respond properly to the insulin produced. Without insulin the body is unable to utilize glucose from the blood, which is necessary for cell function.
Symptoms of DM include excessive urination, drinking and eating, lethargy, depression, anorexia, vomiting, weight loss, sudden blindness or weak rear legs. Animals most prone to developing DM include those who are obese or have a poor diet, older animals, animals under a lot of stress, neutered male cats, female dogs, pets on certain medications and pets who are genetically predisposed to developing diabetes.
A diagnosis of diabetes mellitus is made based on clinical signs, physical examination and laboratory tests. Initial diagnostic lab tests are usually a urinalysis to check for glucose and ketones spilling over into the urine and complete blood work to check for high blood glucose levels and abnormal organ function. Diabetes can cause cataract formation in the eyes of dogs, leading to blindness. Diabetic animals are also more prone to infections (skin, kidney and bladder), slowed healing, and will continue to eat large amounts of food and drink large amounts of water but remain dehydrated and continue to lose weight. Diabetes can be life-threatening if left untreated.
Diabetes is almost always treated using insulin injections and diet change. Insulin injections are typically given 1-2 times daily and cause your pet’s blood glucose to drop to more manageable levels. 80-90% of newly diabetic cats can go into remission using Glargine insulin. If remission does not occur these injections must be given for the duration of your pet’s life.
There are many different types of insulin, and your veterinarian will decide which type and dose will be the safest and most effective for your pet. Determining the correct amount of insulin to give your pet can be a challenging process. Initially, it requires a commitment of time and management from you, the owner, and clear and often frequent communication with your veterinarian.
In most cases we will start your pet on insulin here in the hospital where we will begin by checking blood glucose levels before giving a very low dose of insulin. Your pet will go home for 1 week, and then return to have blood glucose levels checked every 2-4 hours for a 10-12 hour period. Your veterinarian will interpret the results and decide if the insulin dose needs to be adjusted. After this initial glucose curve in the hospital, you may be able to take glucose curves at home if you feel comfortable. Eventually we hope to achieve a dose of insulin that allows for effective regulation of your pet’s diabetes. Once a correct insulin dose is determined periodic blood work and testing of blood glucose levels will still be required at least every 6 months.
Upon your pet’s discharge from the hospital, your veterinarian will show you how to properly give an insulin injection. Insulin should be given at the same time each day, and should only be given after your pet has eaten! If your pet is not eating or has a blood glucose of less than 150, DO NOT give insulin! Insulin should be kept cool at all times and the bottle should be gently rolled prior to withdrawal of the insulin into the syringe. Injections should be given subcutaneously (under the skin) in slightly different spots daily.
Monitoring blood glucose at home is done with a glucometer. Pet-specific glucometers give us the most accurate readings and are quite user-friendly. A lancet or small needle is used to produce a small drop of blood from your pet. The edge of the ear or paw pad works well in cats, and the inside of the upper lip works best in dogs. Perform the prick on a clean, dry area while using gentle restraint. Once a drop of blood appears, place the test strip in the glucometer up to the drop of blood. The blood should be drawn into the test strip and produce a reading. This should be done every 2-4 hours for a 12 hour period.
Dietary management is a crucial aspect of managing your diabetic pet. If possible, your pet should be put on a high-fiber food, formulated specifically for diabetic animals. Purina DCO works well in dogs and Purina DM is great for cats. If your pet is overweight, feeding for weight loss is a necessity for the health of your pet. Avoiding table scraps and feeding on a consistent twice daily schedule are also important considerations, although some cats are “grazers” and will not adhere to a twice daily feeding schedule.
A serious potential side effect of insulin injections is hypoglycemia. Hypoglycemia can be life threatening, and should be treated as an EMERGENCY! Hypoglycemia occurs when your pet’s blood glucose drops to dangerously low levels. You may notice lethargy and weakness, disorientation, wobbling, shivering, restlessness, convulsions or seizures, glassy eyes or unusual vocalizations. If you suspect your pet is hypoglycemic, immediately give Karo syrup. This can be done with a syringe, or by rubbing it on your pet’s gums. This will help to elevate your pet’s blood glucose. Use your glucometer to check a blood glucose level and then call your veterinarian for further advice regarding future insulin dosing and administration. Continue to monitor your pet for several hours to ensure that the hypoglycemia does not recur.