- ...VETERINAIR... ....DIABETES..... ...CONSULENT...
- Berichten: 19652
- Lid geworden op: 18 sep 2005, 12:33
- Locatie: Almelo - Mickey is over de Regenboogbrug maar kreeg ruim 8 jaar Caninsulin.
Created by our own Director of Covert Activities, Walnut (GA)
Insulin is a hormone manufactured in the beta cells of the pancreas. It is a protein composed of two amino acids chains. Because it is a protein it must be injected since the digestive process would destroy the insulin. The A chain has 21 amino acids and the B chain 30. Its main purpose is to open the doors to body cells to allow glucose into each cell so that the body can use glucose as its primary source of energy. In diabetes the body's natural insulin has been impaired or destroyed. Insulin therapy is used to provide the insulin that the body can no longer manufacture or to supplement an inadequate supply of insulin, overcome muscle resistance or increased glucose production by the liver. In approximately 30% of cats oral medicines are sufficient to overcome insulin resistance if there are enough viable beta cells to produce natural insulin. If not, insulin therapy must be used.
Current available insulins used in feline diabetes are manufactured from beef, pork or genetically engineered recombinant human DNA stock or a combination. Beef insulin is the closest match to cat insulin. The only amino acid difference occurs at site A 18. Pork insulin which is identical to dogs has 3 amino acid differences at sites A8, A 10, A18. Human insulin is the furthest removed with a 4 site difference at A8, A10, A18 and B30.
Insulin is sold in a variety of strength and durations. Cats metabolize insulin faster than humans or dogs and usually two shots a day are required. Some cats can manage on one injection of the longest acting insulins such as human Ultralente or PZI.
Insulin is manufactured or compounded in various full or diluted strengths. U 100 strength would be full strength and the most potent. That means it has 100 units of insulin per milliliter of fluid. U50 (available in some compounded insulins) would he half as strong and U 40 is 40% as strong. Diluted insulin can be helpful when trying to adjust insulin dosages in small increments.
Insulin is available in a wide variety of durations. Suffixes after the brand name denote their duration. These suffixes are labeled R (regular), N or NPH (Neutral Protamine Hagedorn), L or Lente (slow) and U or Ultralente (very slow). They differ in their onset, peak and duration.
The more rapid the onset, the less actual amount of insulin is needed to lower bg levels although the duration is much shorter. The slower the onset, the lower the potency therefore higher doses are required.
The length of time before insulin reaches the bloodstream and begins lowering blood glucose.
The time during which insulin is at its maximum strength in terms of lowering blood glucose levels.
How long the insulin continues to lower blood glucose.
Below is a sample of onset, peak and duration times for insulin in HUMANS. In cats the time would be shorter due to their faster metabolism.
Regular or short-acting insulin, referred to with a capital "R," usually reaches the bloodstream within 30 minutes after injection. It peaks anywhere from 1-3 hours after injection, and remains in the bloodstream for approximately 5-7 hours. Semilente would also fall under this category.
Intermediate-acting insulin generally reaches the bloodstream about 2-4 hours after it is injected. It peaks 4-14 hours later, and stays in the blood for about 18-24 hours. The varieties of intermediate-acting insulin include both NPH and Lente.
Long-acting insulins have a minimal peak activity 14-24 hours after they are injected and stay in the blood 20-36 hours. They provide a nearly continuous insulin release. Ultralente and PZI are two long acting insulins.
Below is an general guide of onset, peak and duration for BEEF/PORK insulins when injected subcutaneously in CATS. One could expect a similar but not identical profile for all beef insulins. This guideline may vary on an individual basis.
Regular/SemiLente (Ilentin I Regular)
onset of 10-30 min,
peak 1-5 hours,
duration 4-10 hours
NPH (Ilentin I NPH),
onset 30 min-3 hours
peak 2-8 hours,
duration, 4-12 hours
Lente (Ilentin I Lente)
onset in less than one hour,
peak 2-10 hours,
duration 6-18 hours
Ultralente (Blue Ridge PZI)
onset 2-8 hours,
peak 4-16 hours,
duration 8-24 hours
Insulins are also sold in combination forms such as Humalin 70/30 which combines a mixture of 30% Regular and 70% Nph. Caninsulin is also a combo insulin combining a fast 30 % Semilente with 70% Ultralente in a U 40 strength.
Regular can also be combined with longer acting insulins such as Ultralente or PZI to lower bg's quicker. Adding a unit or two of regular insulin is a useful strategy to employ when onset is slow and can also help combat absorption problems caused by insulin additives or localized allergic reactions. It is also used as a strategy to cope with high glucose surges after meals for cats on long acting insulins.
Insulin mixing should always begin by drawing the regular into the syringe first to avoid contaminating the regular with additives from the Ultralente. It should then be injected immediately to avoid equilibriation between the 2 durations and for consistent results.
Insulin should never be shaken, frozen, subjected to heat or stored in a sunny location. It is best stored in the refrigerator. It can be stored at room temperature which will keep opened bottles of insulin viable for about a month. Most manufacturers feel refrigerated bottles of insulin retain their potency for about 3 months although Lilly's guideline use the more conservative estimates of a month regardless of storage.
Regular Insulin is a clear injectable solution. "N" is a cloudy suspension, "L" is a turbid or cloudy suspension.
Pre-filled syringes are usually viable for about 21 days. Store them horizontally and roll the syringe before injection to resuspend the insulin.
To prepare insulin for injection roll the bottle (Don't shake!) between the palms of your hands until it is well suspended. Draw your syringe to the dosage level and inject air into the bottle . Overdraw your dosage and tap side of syringe to remove air bubbles and inject air and excessive insulin back into the bottle. I would roll the syringe a few more times (kitties hate cold insulin) then inject.
All insulins have added ingredients. These prevent bacteria from growing and help maintain a neutral balance between acids and bases. Buffers are neutral pH with Phosphate or Acetate. Preservatives include M-cresol (Humulin® R), M-cresol/phenol (Humulin® N) or methylparaben (Humulin® L). In addition, intermediate and long-acting insulins also contain ingredients that prolong their actions such as zinc oxide. . NPH has an isopahane suspendsion that differs from the protamine zinc suspension used in Lente and Ultralente and PZI formulations. Additives may vary among different brands of the same kind of insulin and can cause slight differences in the onset and duration of the insulin's action.
In some rare cases, the additives can bring on an allergic reaction.
Insulin Products used for Cats
Human insulins from Eli Lilly: all U100 strength
Humalin R (Regular)
Humalin N (Nph)
Humalin L (Lente)
Humalin U (Ultralente)
Humalin 70/30 (70% N,. 30% R)
Human insulins from Novo Nordisk: all U100 strength
Novolin R (Regular)
Novolin N (Nph)
Novolin L (Lente)
Novolin 70/30 (70% N, 30% R)
Pork Insulins from Eli Lilly: All U100 strength
Ilentin II Regular
Ilentin II Nph
Ilentin II Lente
Pork Insulins from Novo Nordisk: All U100 strength
Purified Pork Regular
Purified pork Nph
Purified pork Lente
Pork insulin from Intevet Canada : Strength is U40
Caninsulin *(Lente mix combo of 30% Semilente and 70% Ultralente)
* (not available in USA)
Pork Insulin from CP Pharmaceuticals: All U100 Strength
Hypurin Porcine Neutral (Regular)
Hypurin Porcine Isophane (Nph)
Hypurin Porcine 70/30 ( combo 70% Nph, 30% R)
Beef/Pork insulins from Eli Lilly: All U100 Strength
Ilentin I Regular (discontinued)
Ilentin I Nph (discontinued)
Ilentin I Lente (discontinued)
Beef/pork insulin from Blue Ridge: Strength is U40
Beef insulins from CP Pharmaceuticals: All U100 Strength
Hypurin Bovine Neutral (Regular)
Hypurin Bovine Isophane (NPH)
Hypurin Bovine Lente
Hypurin Bovine PZI