Insulins commonly used in dogs and cats
- Lente (U-40 porcine insulin zinc suspension; Vetsulin, Merck Animal Health) is an intermediate-acting insulin commonly used by the Task Force in dogs. It is FDA approved for use in dogs and cats. It has a close to 12 hr duration of action in most dogs and is useful for minimizing postprandial hyperglycemia.
- Glargine (U-100 human recombinant; Lantus, Sanofi) is a longer-acting insulin commonly used by the Task Force in cats because it has an adequate duration of action in most diabetic cats. Several studies have demonstrated that glargine is effective for controlling blood sugar levels in diabetic cats and achieving high remission rates.Glargine can also be used in dogs. It is a human analog insulin with modifications that provide variable solubility at different pHs. Glargine is soluble at a pH of 4.0, the pH at which it is supplied and stored, but in the neutral pH of the body’s blood or subcutaneous tissues it forms microprecipitates, facilitating slow absorption after injection. This results in rapid onset and long duration of action. Glargine is sometimes described as a “peakless” insulin, although peakless does not mean an absence of a nadir in cats but rather refers to glucose utilization rates.In dogs, a flat blood glucose curve (BGC) may be seen, so glargine can be referred to as a peakless insulin in that species.
- PZI (U-40 human recombinant protamine zinc insulin; ProZinc, Boehringer Ingelheim Animal Health) is considered by clinicians as a long-acting insulin, and is FDA approved for use in cats. In field studies in cats, mean time of the BG nadir was between 5 and 7 hr and the duration of action was 8–24 hr, which was deemed an appropriate duration of action by the FDA. results suggested that Prozinc should be administered twice daily in most diabetic cats to maintain control of glycemia.This insulin is used in both cats and dogs, although it is less commonly used in dogs. Protamine zinc insulin can have a prolonged duration of action in dogs and may be tried on once-daily dosing schedule to minimize the chances of clinically significant hypoglycemia and/or the Somogyi phenomenon.
- NPH (U-100 human recombinant; Neutral Protamine Hagedorn Humulin N, Lilly or Novulin N, Novo Nordisk) is an intermediate-acting insulin that is used in dogs. The Task Force does not recommend use of this insulin in cats due to its short duration of action. The duration of action of NPH in dogs is often <12 hr. Some dogs can have postprandial hyperglycemia when treated with this insulin.A combination form of NPH plus regular insulin (70 NPH/30 Regular) is available that may be suitable if the dog has an appropriate duration of action (8–12 hr) with an early nadir or postprandial BG spike. Some clinicians use this product in dogs who develop postprandial hyperglycemia when being treated with NPH.
- Detemir (U-100 human recombinant; Levemir, Novo Nordisk) is a long-acting insulin that can be used in both dogs and cats. Detemir is a human analog insulin engineered with modifications that allow it to bind albumin with high affinity in the subcutaneous and intravascular spaces, prolonging the insulin’s absorption. This prolonged absorption gives detemir a long and steady duration of action and less variability in biological activity.Detemir has a very similar profile to glargine (Lantus) in cats in terms of BG control and remission rates. However, cats receiving detemir require a lower median maximal dose than cats receiving glargine (1.75 U per cat for detemir versus 2.5 U per cat of glargine). Dogs are very sensitive to the higher potency of this insulin and require lower starting doses (0.1 U/kg). Particular caution must be used in small dogs because they are more likely to have more frequent hypoglycemic excursions.