Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
DRUG CLASS AND MECHANISM: Insulin is a naturally-occurring hormone secreted by the pancreas. Insulin is required by the cells of the body in order for them to remove and use glucose from the blood. From glucose the cells produce the energy that they need to carry out their functions. Researchers first gave an active extract of the pancreas containing insulin to a young diabetic patient in 1922, and the FDA first approved insulin in 1939. Currently, insulin used for treatment is derived from beef and pork pancreas as well as recombinant (human) technology. The first recombinant human insulin was approved by the FDA in 1982.
diabetes mellitus have a reduced ability to take up and use glucose from the blood, and, as a result, the glucose level in the blood rises. In type 1 diabetes, the pancreas cannot produce enough insulin. Therefore, insulin therapy is needed. In type 2 diabetes, patients produce insulin, but cells throughout the body do not respond normally to the insulin. Nevertheless, insulin also may be used in type 2 diabetes to overcome the resistance of the cells to insulin. By increasing the uptake of glucose by cells and reducing the concentration of glucose in the blood, insulin prevents or reduces the long-term complications of diabetes, including damage to the blood vessels, eyes, kidneys, and nerves. Insulin is administered by injection under the skin (subcutaneously). The subcutaneous tissue of the abdomen is preferred because absorption of the insulin is more consistent from this location than subcutaneous tissues in other locations.
PRESCRIPTION: Yes; No (regular and NPH insulin)
PREPARATIONS: Types of Insulin
Regular (Humulin R, Novolin R) insulin has an onset of action (begins to reduce blood sugar) within 30 minutes of injection, reaches a peak effect at 1-3 hours, and has effects that last 6-8 hours.
NPH insulin (Novolin N, Humulin N) is an insulin with an intermediate duration of action. It has an onset of action starting about 2 hours following injection. It has a peak effect 4-12 hours after injection, and a duration of action of 18-26 hours.
Lente insulin also is an insulin with an intermediate duration of action. It has an onset of action 2-4 hours after injection, a peak activity 6-12 hours after injection, and a duration of action of 18 to 26 hours. Lente insulins have been discontinued.
Ultralente insulin is a long-acting insulin with an onset of action 4-8 hours after injection, a peak effect 10-30 hours after injection, and a duration of action of more than 36 hours. Ultralente insulins have been discontinued.
Novolog (Insulin aspart) is a human insulin with a slightly modified chemical composition. The chemical changes provide insulin aspart with a faster onset of action (20 minutes) and a shorter duration of action (3-5 hours) than regular human insulin. It reaches peak activity 1-3 hours after injection.
Humalog (Insulin Lispro) is an ultra rapid-acting insulin. It is a chemically-modified, natural insulin. It was approved by the FDA in June, 1996. As compared to regular insulin, insulin lispro has a more rapid onset of action, an earlier peak effect, and a shorter duration of action. It reaches peak activity 0.5-2.5 hours after injection. Therefore, insulin lispro should be injected 15 minutes before a meal as compared to regular insulin which is injected 30-60 minutes before a meal.
Apidra (insulin glulisine recombinant) is also a chemically modified human insulin. It has an onset of action of 20-30 minutes, peaks at one hour and its duration of action is 5 hours.
Lantus (insulin glargine recombinant) is a human insulin with a slightly modified chemical composition. The chemical changes provide Insulin glargine with a slower onset of action (70 minutes) and a longer duration of action (24 hours) than regular human insulin. Its activity does not peak.
Levemir (insulin detemir recombinant) is modified human insulin with an onset of 3-4 hours a peak of 6-8 hours and duration of up to 24 hours.
Insulin comes in three different forms-vials, prefilled syringes, and cartridges. The cartridges are to be used in a pen-like device that simplifies injection.
Regular human insulin (Novolin R, Humulin R) is available in vials, cartridges, and prefilled syringes.
NPH human insulin (Novolin N, Humulin N) is available in vials, cartridges and prefilled syringes. A mixture of 70% NPH human insulin and 30% regular human insulin (Novolin 70/30, Humulin 70/30) is available in vials, cartridges and pre-filled syringes.
A mixture of 50% NPH human insulin and 50% regular human insulin (Humulin 50/50) is available in vials.
Insulin lispro (Humalog) is available in vials and cartridges.
Insulin aspart (Novolog) is available in vials and cartridges.
Insulin glargine (Lantus) is available in vials and cartridges.
Levemir (insulin detemir): Supplied in a vial, prefilled pen (FlexPen)
Apidra (insulin glulisine): Supplied in a cartridge, vial, prefilled pen (Solostar)