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CHANGING TO HUMALOG? WHAT YOU NEED TO

KNOW ON A PUMP

by John Walsh, PA, CDE and Ruth Roberts, MA

(Editor's Note: The authors mention many texts in this article -- and all

are either pages on their website, or publications available for purchase at

The Diabetes Mall. Reprinted with permission.)

Humalog compared to Regular

How to improve Humalog's effectiveness

Humalog in pumps

Safety issues

Clinical research findings

See also Can Humalog Handle The Heat? and Users' Reports

Humalog is a fast-acting insulin that gives users greater flexibility and better

blood sugar control. Produced by Lilly and released in 1996, this insulin offers

a quicker action time than the original Regular insulin, developed in 1921.

With its higher peak activity and shorter working time, users report that their

eating can be more spontaneous, their control is improved and they feel better.

Although Lilly has not applied for FDA approval to use Humalog in insulin

pumps, the majority of pumpers in the U.S. have already switched and appear

to be very satisfied. Novo-Nordisk is planning the release of their fast-acting

Novolog or aspart insulin into the U.S. market following the anticipated FDA

approval late in 1999. They may also seek FDA approval for pump use for Novolog.

Humalog Compared To Regular

Like Regular, Humalog is used to cover meals and snacks. Most meals create

a rise in the blood sugar for only a short period, normally two to three hours

for most foods. Regular insulin takes 30 minutes to begin working, does not

peak until three to four hours after the injection, and continues to lower blood

sugars for six to as much as eight hours. Humalog, on the other hand, begins

working in 10 minutes, peaks at one to two hours and is gone in about 3 and

1/2 hours.

The great advantage of Humalog is that it can be taken as you begin eating,

rather than 30 to 45 minutes earlier, required of Regular, because it matches

the "action time" for most meals. For mothers of small children and for those

on the go, this is a tremendous advantage. Rather than having to anticipate

when the next meal might begin, those who aren't sure when the next meal might

begin and those feeling ill can simply wait to bolus as they begin eating. Kids

who are picky eaters can be given a bolus after they actually finish the meal

with little loss of control.

Humalog simply matches meals better, lowering the blood sugar at the same

time the food is raising it. Blood sugars at one to two hours after eating do

not spike as they often do with Regular, and by the end of the second hour the

blood sugar is often close to its starting point. This shorter action time gives

Humalog a cleaner action pattern meaning the action of the last meal bolus is

gone before the next meal begins.

More important for many, there is no residual bolus activity before going

to bed and fewer nighttime reactions. Humalog leaves your body more quickly

so you don't have residual insulin causing low blood sugars in the late afternoon

or in the middle of the night. With Humalog you're better equipped to stop blood

sugars spiking between meals, and you're no longer exposed to the overlapping

build-up of Regular boluses.

Humalog's clearly defined action time makes it easier to troubleshoot problems.

For information on how to determine the number of carbs covered by each unit

of Humalog, see the 500 Rule in the POCKET PANCREAS. Humalog is also excellent

for lowering high blood sugars. Its faster action means that less time is spent

at high blood sugar levels, and less residual insulin is left to trigger low

blood sugars later. For information on how to safely lower highs, see the 1800

Rule, also in the POCKET PANCREAS.

These rules work when someone has their basals and boluses set up correctly

and has tested their doses to make sure their total daily insulin dose is correct.

Techniques To Improve Humalog's Effectiveness

Test often. Test your blood sugar often to determine how Humalog works best

for you. As you start using Humalog, it is wise to test before eating, two hours

after eating, and any time you experience unusual symptoms. Test often and use

special caution when lowering high blood sugars.

Covers food differently. The great advantage of Humalog is its convenience.

Although a 10 to 20 minute lead time is ideal, boluses can be taken with the

first bite of food with very good post-meal control. Of course, its quick action

means that you must not delay eating! If the pre- meal blood sugar is high and

eating is delayed to allow the blood sugar to drop, the food must be eaten at

the time planned to avoid a low blood sugar.

Foods with a high glycemic index that raise the blood sugar quickly, like

cold cereals or a scone for breakfast, are easier to cover with Humalog. However,

low glycemic carbohydrates like pasta al dente or a bean burrito which digest

more slowly can present some problems, such as hypoglycemia occurring before

these foods completely digest. For these rare foods with a low GI, the bolus

may be split. Take half before the meal and the second half an hour or two after

eating, or use a square wave bolus or raise the basal rate temporarily. Another

option is to give an injection of Regular to better match these slow carbohydrates.

The 500 Rule

Total Daily Insulin Dose

Covered by One Unit of Humalog

Approximate Grams of Carb

20

25

25

20

30

17

35

14

40

13

50

10

60

8

The 1800 Rule

Total Daily Insulin Dose

Estimated Point Drop per

Unit of Humalog

20

90 mg/dl

25

72 mg/dl

30

60 mg/dl

35

51 mg/dl

40

45 mg/dl

50

36 mg/dl

60

30 mg/dl

75

24 mg/dl

100

18 mg/dl

Meals with a high fat content may also occasionally be best covered by taking

a split dose of Humalog, or taking the whole dose after the meal is eaten to

better match the slow digestion of these meals. And, of course, if your blood

sugar is low or on the edge of low at mealtime, eat the meal and then take your

bolus afterwards.

Treat lows differently. Because of Humalog's fast action, fast carbs are recommended

when you need to treat a low blood sugar. Glucose tabs, honey, or candies with

dextrose like Sweet Tarts work best. Low blood sugars usually occur within three

to 3 and 1/2 hours of a bolus. Obviously, if a low blood sugar occurs one or

two hours after a bolus, more carbohydrate will be needed to raise the reading

back to normal, than if the low happens three or four hours after the bolus.

At three hours, a small amount of carbohydrate (10 to 20 grams) is usually all

that's needed to remedy the situation.

Another great benefit of Humalog is that fewer lows are experienced during

the night. People often needed a bedtime snack when using Regular in their pump

to avoid a low during the night. In contrast, Humalog can be used at dinner

with little need for a bedtime snack if the nighttime basal is correctly set.

More Pump Info

Many research studies have reported that insulin boluses remain the same when

people switch from Regular to Humalog. However, there are several reasons to

be alert for changes that are likely to be needed in insulin doses. Because

meals are covered more precisely with Humalog, often less insulin is needed

to cover them. On the other hand, Humalog's shorter bolus action time may require

a higher basal rate during the day. With Humalog, we recommend that the basal

rate make up 50% to 60% of the total daily insulin dose.

In research on Humalog's biologic activity, two of six studies found that

Humalog was as much as 10% more active than Regular in lowering blood sugars,

while the other four found its activity was identical to Regular. So be alert

if a unit of Humalog seems to go farther than a unit of Regular. Any change

in insulin doses should only be attempted after discussing them thoroughly with

your physician.

Many pumpers using Humalog report they need slightly less insulin through

the day. Some find boluses may need to be reduced as much as 10 to 25%. Basal

rate amounts generally don't change, although some find they need to raise the

basal rate in the late evening and early nighttime hours because they used to

rely on Regular's long action to work into the nighttime hours.

With Humalog's greater speed, basal rate changes are made closer to the actual

time they are needed. For instance, on Regular, if the basal rate is raised

at 2 a.m. to offset a Dawn Phenomenon, raising the basal rate might be delayed

until 3 a.m. on Humalog.

For safety's sake, do not use the suspend feature with Humalog for exercise

or low blood sugars. If you forget to take it out of suspend, you can quickly

end up with high blood sugars. Because of its short action time, blood sugars

typically begin to rise 60 to 90 minutes after the insulin is suspended, unless

a bolus was taken recently. Another reason to never use suspend is that insulin

which is static in the infusion line encourages clogging.

Always take Humalog by injection at the FIRST high blood sugar reading over

300 mg/dl (17 mmol). If any delivery problem occurs with Humalog in your pump,

blood sugars can start to rise within 60 to 90 minutes, and ketoacidosis can

begin in 4 to 5 hours. If a SECOND reading taken 90 to 120 minutes later is

still over 300 mg/dl, take Humalog by injection and change out the reservoir

and infusion set.

Clinical Research Findings

Results from 23 clinical research studies using Humalog in Europe, Canada

and the United States were reported at the 1997 American Diabetes Association

meeting in Boston. Our analysis of these studies found positive results in four

areas when comparing Humalog with Regular:

Humalog gives better readings one to two hours after meals. Usually Humalog

was given at the start of a meal, but even when taken 15 minutes after a meal

Humalog gives better post-meal readings compared to Regular taken 40 minutes

before a meal.

Blood sugars are improved through the entire day due largely to improved

readings after meals.

The HbA1c is lowered by an average of 0.5%.

Humalog improves quality of life.

Other results in individual studies were also positive. In one study, two

people who had hypoglycemia unawareness regained warning symptoms of a low blood

sugar. In a study of adolescents, incidents of nighttime hypoglycemia decreased.

The subjects in most of the research studies above were type 1's on long-term

intensive management who had good control with HbA1cs in the 7s or 8s before

using Humalog in the study. But one study followed people with "brittle diabetes"

with erratic blood sugars and high HbA1c's. On switching to Humalog from Regular,

their diabetes improved in all four areas listed above. Another study using

people with type 2 diabetes also reported these improvements and the subjects

had no weight gain.

Cautions About Heat And Storage

Some people have noticed unexpected high blood sugars with Humalog and report

that Humalog may deteriorate faster in hot weather than Regular. Control problems

can certainly occur for other reasons such as incorrect basals and boluses that

do not match the body's need for insulin. But Humalog appears to be less stable

than Regular and more likely to lose activity, especially when exposed to heat.

Test often and if your insulin does not appear to be having its expected effect,

check for particles in the bottle and open a new bottle.

Storage Tips:

Keep refrigerated or cooled at all times

If shipped by mail, UPS, etc., demand it be cooled during shipment

Never leave in a car

If you have a high, don't automatically assume it's your fault!

When Humalog goes bad, it does so quickly. Blood sugars may be fine one day

and high the next. If blood sugars are unexpectedly high for any reason, check

for particles, usually one or two large floaters, or several small crystals

in solution or on the sides of the bottle. Always start a new bottle if you

have any doubts.

In summary, the overwhelming majority of pumpers who have tried Humalog have

gladly stayed on it. Most have been impressed by improvements in their control

and in the convenience of taking their insulin when they eat. Fewer lows at

night and improved HbA1c reports are a few of the benefits pumpers have experienced

with Humalog, and many report that they feel better on this fast insulin.

For more information on Humalog and many other areas of intensive management,

carbohydrate counting, glycemic index, proper insulin doses, exercise with control,

pregnancy, complications, etc., get PUMPING INSULIN and the POCKET PANCREAS

by John and Ruth, or STOP THE ROLLERCOASTER by John, Ruth, and Lois Jovanovic-Peterson,

MD. Order these books online at (http://www.diabetesnet.com)

or call The Diabetes Mall at (800) 988-4772 (011-1-619-497-0900) to order your

copy.

Copyright (c) 1997, 1999 by Diabetes Services, Inc.

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