Insulin dosage

INSULIN AND ITS DOSAGE FORMS

1-Rate of insulin infusion:
i-If blood glucose level is less than 4mmol/lit. than give 0.5 units of insulin per hour.
ii-If blood glucose level is less than 4-15mmol/lit. than give 2 units per hour.
iii- If blood glucose level is less than 15-20mmol/lit. than give 4 units per hour

2-TYPES OF INSULINS

All insulin is not the same. Insulin actually comes in several forms. Each of these forms are designed to work at different rate. The following are seven of the common forms of insulin that are commonly administered to a diabetic:

1. Lispro

Lispro is a very rapid acting form of insulin. Within five minutes of administering Lispro blood glucose levels begin to drop. It remains active in lowering blood glucose levels for about 2.5 hours, though it is most effective when it has been in the blood about 1 hour. Because it does not remain active very long, Lispro has less chance of inducing a hypoglycemic reaction several hours later.

2. Normal insulin

Normal insulin starts working in about thirty minutes. It works most effectively after it has been in the body for about three hours, but it can continue working in the bloodstream for nearly seven hours.

3. NPH

This form of insulin has been designed to mimic the insulin produced inside the human body. It lowers blood glucose levels at a more consistent rate. It reaches its peak when it has been in the bloodstream about 2 hours, but remains at peak for up to 12 hours. It continues working for about 24 hours total, though not as vigorously in the last 10 hours

4. Lente

Lente is another insulin that is designed to work like the insulin that naturally occurs inside the human body. It works over long periods of time, but takes about two hours to reach its peak effectiveness in lowering blood sugar. It will continue at its peak for about half of the day and then function more moderately the second half of the day.

5. Ultralente

Ultralente was designed with the idea of providing a once per day insulin option. It takes nearly six hours after taking Ultralente before it starts lowering blood glucose levels. However, it continues functioning effectively all day long.

6. Glargine

Glargine is a popular insulin that is used mainly with type 1 diabetes. This is a long acting form of insulin that is injected just once per twenty four hours. Great care must be taken not to contaminate this insulin with the other forms of insulin by using the same syringe or storage equipment.

7. Pre-Mixed Insulin

Pre-mixed insulins are popular because they help take patient dosage and administration errors out of the diabetic treatment equation. e.g HUMULIN 70/30

Dosage forms of insulin

1-Standard mode of therapy:

Standard mode of insulin therapy is subcutaneous injection using conventional disposable needle and syringes.

2-Portable pen injection:

To facilitate subcutaneous injection of insulin, particularly during intensive insulin therapy. portable pen sized injections have been developed.It inject measureable quantity of insulin.

3-Disposable insulin pens:

disposable insulin pens are also available for selected formulations e.g regular insulin ,insulin lispro, insulin aspart, insulin glulisine, glargine etc

4-Continuous insulin infusion devices(insulin pumps):

These are external open loop pumps for insulin delivery. it has user programmable pump that delivers individualized basal and bolas insulin replacement doses based on blood glucose self monitoring results. these are implanted subcutaneously always.

5-Buccal dosage forms :

As insulin is degraded in acidic  pH.  buccal film of insulin may be very useful for the treatment of diabetes more efficiently. the release mechanism is diffusion controlled and rate of diffusion was by first order kinetics. a significant reduction of blood sugar was observed at 2 hr

6-Inhalation:

A new ultra rapid acting mealtime insulin that is orally inhaled for absorption via the lung ,that closely mimics the normal early insulin response seen in healthy individuals. a thumb size device is used and patient inhales a small amount of the powder, this drug is rapidly absorbed ultra rapid so it become effective much more quickly than an injection of same drug(matches the body’s natural responses in processes like secretion).
Fig: Insulin inhalation device