Insulin's Role
Without insulin, the body is unable to utilize sugar
present in the bloodstream for energy. Just as it's
important to have the right key to unlock a door, it's
important to use the right insulin to unlock cells so
available sugar can be used. As with most aspects of
diabetes, there can be both similarities and differences
in the way individuals react to various kinds of insulin.
Seek your doctor's advice before making any additions or
changes to your regimen. Until recently, most insulin was
made from the pancreases of pigs or cattle. More common
today are synthetic versions, genetically engineered and
structurally identical to that made by a functioning
human pancreas. Because insulin is a protein destroyed by
digestive enzymes, it must be taken by injection,
although some inhaled forms are now being evaluated for
their efficacy.
How It Works
Insulin
is produced in different strengths and a variety of
types, each classified according to how fast it begins to
work, how long until its action reaches its peak, and how
long the effect lasts.
Some types of insulin can be combined in a single
syringe, or purchased pre-mixed to decrease the number of
injections necessary. Other types must be injected
individually. Talk to your doctor or diabetes educator to
determine
what types are best for you and whether they
can be mixed or must be injected separately to achieve
maximum effectiveness. Humalog (manufactured by Lilly)
and Novolog® (manufactured by Novo Nordisk) are the
quickest acting types of insulin. Their rapid onset makes
Novolog and Humalog ideal for those who count
carbohydrates and cover their meals and snacks with
injections. The FDA has approved Novolog for use in
insulin pumps.
All insulin comes dissolved
or suspended in liquids, but the solutions have different
strengths. In the United States, the most commonly used
strength is U-100. That means there are 100 units of
insulin per milliliter of fluid. Other strengths are
available but are rarely used in the United States. Make
sure that you understand the difference when traveling
abroad.
Lilly and Novo Nordisk also
manufacture short-acting insulin, commonly referred to as
Regular insulin, regular insulin which generally takes
anywhere from thirty minutes to two hours to begin acting
and continues working for four to six hours.
Intermediate range insulin is also made by Lilly and Novo
Nordisk. Whether referred to by the brand names of
Humulin® and Novolin®, or the generic NPH and Lente, this
type takes longer to begin acting, has a longer peak, and
remains working in the body longer than Regular, Novolog
or Humalog. Both NPH and Lente are used when long-range
coverage is desired.
Lantus (manufactured by
Aventis) and Humulin UltraLente (manufactured by Lilly)
are newer forms. Both UltraLente and Lantus are designed
for use as basal insulin, meaning that they provide
coverage for the small, continuous need for insulin
rather than the additional bursts needed when food is
digested.
Body weight, activity level, food
eaten, illness, stress, and insulin sensitivity (or
resistance) all contribute to the complex equation
determining how much insulin is needed by an individual
at a specific time. As factors in your lifestyle change,
it's likely that your needs will vary. Be sure to consult
with your healthcare professional before making any
changes to your regimen.
