Instructions for Taking Insulin for Type-2 Diabetics

By Editor |

Friday, December 23, 2011

[Note:  It's necessary for me to say at the beginning of this article that I am a diabetic patient, not a doctor.  I have written this article to share the knowledge that I have gained by dealing with my own diabetes.  However, my advice should not be taken as a substitute for a doctor's advice.  Indeed -- and most importantly -- you should not diagnose yourself as having diabetes.  Also, you should not inject insulin unless your doctor has told you that it is okay to do so.  When you begin insulin, it is important that you start out with small doses, increase the insulin gradually, and always inject the insulin into fat.  In my opinion, you won't suffer any peril from taking my advice, but that's only my opinion.

[Since beginning insulin in 2011, new insulins may have come on the market.  Personally, I have only taken Regular and 70/30 insulin, so I have no experience with the other insulins that I describe.  If you feel that any of my information is inaccurate, please leave a comment on the article.]

When I was prescribed insulin in March, 2011, neither my doctor nor the nurse told me much about how to take it.  I was a very knowledgeable patient, so I wasn't entirely in the dark.  However, if I had been less knowledgeable, the entire experience could have been a nightmare.  I have typed up here the information sheet that I wish I had been given, and which would have saved me a lot of confusion.

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You have been given this sheet because your doctor has just prescribed insulin for you.  This sheet will answer most of your questions.

When to Take Your Insulin

Glargine (Lantus)

Lantus is a newer long-acting insulin.  You can inject it once a day, but its action will be smoother if you divide your dose and inject it twice a day.  If you inject it once, it is best to inject it in the mornings before eating breakfast.  If you inject it at bedtime, it may not last as long in your system.

Lantus is a "basal" insulin.  It is designed to keep your basal or fasting blood-sugar levels under control.  It is not designed to handle the surge of blood sugar that occurs after meals.  If Lantus is the only insulin your doctor has prescribed, it will work best if you keep your consumption of carbohydrates low (100 grams per day or less) so that your post-prandial (post-meal) blood-sugar levels do not rise too high.  Lantus remains in your system for 18 to 20 hours after injecting.

(Note:  The durations given in this article are approximate.  Also, small injections will last a shorter time in your system than large injections simply because it takes longer for a large injection to be absorbed.  Thus, an injection of 5 units will last less time than an injection of 30 units, which in turn will last less time than an injection of 60 units.  This is true for all insulins.)

Detemir (Levemir)

Levemir is also a newer long-acting insulin.  It must be injected twice a day.  The best times are before eating breakfast, and then again twelve hours later.

Levemir is a basal insulin.  It is designed to keep your basal or fasting blood-sugar levels under control.  It is not designed to handle the surge of blood sugar that occurs after meals.  If Levemir is the only insulin your doctor has prescribed, it will work best if you keep your consumption of carbohydrates low (100 grams per day or less) so that your post-prandial blood-sugar levels do not rise too high.  Levemir remains in your system for about 12-15 hours after injecting.

NPH (Humulin N, Novolin N)

NPH is an older basal insulin.  NPH remains in your system for about 8 hours after injecting.  Its action is not as smooth as Lantus or Levemir (meaning that it has more of a curve or peak).  It is not designed to handle the surge of blood sugar that occurs after meals; but since it has a peak, it is better at that than the newer basal insulins.  Since NPH remains in your system for about 8 hours, you should inject it two or three times a day, depending on when you eat and how much carbohydrate you are consuming.  Most doctors do not prescribe NPH by itself, but as part of a mix of basal and fast-acting insulins (see below).

Regular insulin (Humulin R, Novolin R)

Regular insulin is a fast-acting insulin which is identical to human insulin.  You should inject it 30-60 minutes before a meal.  Once it takes effect, it lasts for about 5 hours in your system.  During that time you should be able to eat two meals, or a meal and a snack, separated by two or three hours.

Since the amount of insulin you need is proportional to the amount of carbohydrates you eat, you can avoid taking three injections a day if you eat little or no carbohydrates at one of your meals, before which you would not take a shot.  Alternatively, if you eat two meals on each shot, that will allow you to eat four meals a day, although the meals will not be spaced evenly throughout the day.  You can, for example, eat breakfast and lunch on one shot, and dinner and a bedtime snack on another shot.  (More on this later.)

Fast-acting insulins are called "bolus" insulins.  They are designed to handle the surge of blood sugar that occurs after meals.  If you inject enough bolus insulin to handle your meals, you may find that your fasting blood-sugar levels are reasonably low, so you may not need to inject basal insulin also.

Aspart (Novolog), Lispro (Humalog) and Glulisine (Apidra) are very-fast-acting insulins which are not likely to be prescribed to a diabetic who is just starting injections, so they won't be discussed here.  They are generally used by diabetics who are trying to achieve very tight control of their blood-sugar levels.

Although they are fast-acting, bolus insulins take hours to work their way through your system because they must be injected into fat, and it takes time for your body to absorb the insulin from your fat.  Insulin which is released by your pancreas goes straight into your blood and has a much faster action than even the fastest injected insulin.  See "How to Inject Yourself" below.

Insulin mixes (Humulin 70/30, Novolin 70/30)

NPH and Regular insulin come mixed together in proportions of 70% to 30%.  Mixed insulins should be injected 30 to 60 minutes before a meal.  You can eat more carbohydrates on mixed insulin than on basal insulin alone, but you should still try to keep your carbohydrates to a moderate level.  Mixed insulins remain in your system for about 8 hours after injecting.  The best times to inject are before breakfast and before dinner.  On the first injection, you can eat breakfast and lunch (if you eat lunch within 4 hours of eating breakfast); on the second injection, you can eat dinner and a bedtime snack.

Combining R with 70/30 or NPH

As stated above, you can eat two meals on a shot of Regular insulin.  The meals, however, should not be more than about three hours apart.  Thus, you could inject R insulin at 8:30 a.m., eat breakfast at 9:00 a.m. and then lunch at noon.  (Even though the injection would be effective until about 2:00 p.m., you need to eat your second meal a couple hours before it runs out.)  However, it is possible to space your meals more widely if you mix R insulin (which is effective for 5 hours) with 70/30 insulin or NPH insulin (which are effective for 8 hours).  Mixing R with 70/30 or NPH will give you the R insulin you need to cover your meals, but it will also give you some of the NPH insulin to bring your blood sugar down when the meals are over.

On a mixture of R and 70/30 or R and NPH, you could inject your insulin at 8:30 a.m., eat breakfast at 9:00 a.m. and then lunch at 1:00 p.m.  In the evening, you could inject your insulin at 5:30 p.m., eat dinner at 6:00 p.m., and then have a large snack at 10:00 p.m. or even later.

You may have noted that 70/30 already has R insulin in it, but it may not be enough to cover your meals, and that's why you may want to mix in additional R insulin.  A mixture of R to NPH of 50/50 used to be sold, but it was disctonued.

Combining R with 70/30 or NPH requires only one shot; the two insulins are mixed in one syringe.

Injecting Insulin to Bring Down High Blood-Sugar Levels

The injection methods above all indicate that you should inject insulin before eating.  However, if your blood sugar is high before you eat, you can inject more insulin than usual before you eat again.  How much more will depend on many factors:  your recent diet; your projected diet; whether your liver might be releasing glycogen (see below); etc.  Learning how much insulin to inject in such circumstances is a matter of trial and error.

If your blood sugar is very high -- say, from slipping off your diet -- you may inject insulin to bring it down even if you have no intention of eating after the injection.  In such circumstances, however, you will likely need less insulin than you usually inject before meals.  Again, through trial and error you will learn how much insulin to inject.

Testing Your Blood Sugar

Using your personal glucose meter, you should test your blood-sugar at different intervals.  You should always test your blood-sugar in the morning before eating.  You should also test 90 minutes after your largest meal, and then 90 minutes after that.  On some days you should test after lunch, and on other days you should test after dinner, just to get an idea of what is happening with your glucose levels.  You should strive to get your blood-sugar levels as close to normal as possible, as follows:

Time	Normal (mg/dl)	Excellent Control	Good Control	Poor Control
After rising	80-90	120 or less	140 or less	150 or more
60 to 90 minutes after eating	90-130	150 or less	170 or less	180 or more
2:00 to 3:00 hours after eating	80-90	120 or less	140 or less	150 or more

Note:  Some diabetics experience slow emptying of the stomach.  For those, the times in the chart may be longer.

Dosage

Your doctor has started you out with a low dosage of insulin, a dosage which is probably less than you need.  This is necessary in order to avoid the possibility of an overdose.  Unless your doctor has asked you not to, you may gradually increase the size of your insulin shots until your blood-sugar numbers begin to look more normal.  You should not increase your dosage by more than one unit per day.  There is no upper limit to the amount of insulin you may need to take, but you should keep your doctor informed of the changes in dosage.  You should return for a follow-up visit within 60 days to discuss your progress.

The Role of Carbohydrates

The size of the injections you take will be largely determined by the amount of carbohydrates you eat (i.e., starchy foods and sweets).  That is because blood sugar comes mainly from dietary carbohydrates.  Thus, the fewer carbohydrates you eat, the less sugar will enter your blood, and the less insulin you will need to inject.  If you take very large injections of insulin so that you can eat large amounts of carbohydrates, you will probably gain weight (just as a non-diabetic would gain weight if he or she overate on carbohydrates).  The upper limit that any diabetic should eat is about 200 grams of carbohydrates a day.  150 grams are better, and 100 grams are better still.

In your quest to reduce your carbohydrates, you should not eliminate low-carbohydrate vegetables from your diet, which are needed for good nutrition.  The starches that you do eat should be whole-grain and high-fiber.  Desserts should be kept to a minimum.

You should try to eat a consistent amount of carbohydrates from one day to the next.  That way you can inject the same amount of insulin every day.  This will allow you to figure out a workable insulin-to-carbohydrate ratio.  A common ratio is one unit of insulin for every three grams of carbohydrates eaten, but the ratio that works for you may be lower or higher.

In order to count your dietary carbohydrates, you should pick up a book that contains carbohydrate values (most calorie-counting dictionaries list carbohydrates also), or you can use any of these internet sites:

http://caloriecount.about.com/

http://www.carb-counter.org/

http://www.myfitnesspal.com/ 

(If any of these web sites are no longer active, you should do a search for "carbohydrate counter".)

Most commercial foods give the carbohydrate count right on the label.

When counting carbohydrates, you can deduct the amount of fiber from the carbohydrate total to come up with a net figure for the food you are eating.  In other words, fiber is included in the total carbohydrate count for a food; but since it is indigestible, the fiber can be subtracted from the total.  For example:  If a serving of food has 20 grams of carbohydrates (in total) and 5 grams of fiber, you can count that food as having 15 grams of carbohydrates.

The Action of the Liver

Blood sugar can be stored as glycogen (a form of starch) in various parts of the body, especially the liver.  This stored blood sugar can complicate matters when you start a diet or start injecting insulin.  For the first one to six weeks, your liver may release sugar into your blood every day, keeping your blood-sugar numbers frustratingly high.  If you are eating a very low-carbohydrate diet (50 grams a day or less), it may take a week or less for this to stop; but if you are eating a high-carbohydrate diet (200 grams a day), it may take more than a month for these releases of glycogen from your liver to stop (these releases are informally called "liver dumps").  Thus, during the first month or two of taking insulin, you need to be patient if your blood-sugar numbers are not as low as you hoped.

Because of the action of the liver, you do not want to increase your insulin too rapidly in the beginning (lest the "liver dumps" stop and your blood sugar suddenly drop too low).  If, after eight weeks of taking insulin, your blood-sugar numbers are not close to normal, it is safe to make significant increases in your insulin dosage.  Remember, however, that a high-carbohydrate diet will work against your efforts to lower your blood-sugar levels.  If you continue to eat a high-carbohydrate diet, your liver will continue to store blood sugar, and "liver dumps" may be an ongoing problem, giving you high blood-sugar readings at unexpected times.

The Dawn Phenomenon

You may find that your blood sugar is higher in the morning than it was at bedtime.  This is due to the "dawn phenomenon".  As the morning approaches, your liver releases glycogen, which raises your blood-sugar (presumably your liver does that to help you wake up).  In a non-diabetic, the pancreas will then release insulin to prevent the blood sugar from going too high, but this doesn't happen in a diabetic.  If you don't take insulin or eat something small after waking, your blood-sugar will continue to rise.  Eating something small should stimulate a release of insulin from your pancreas.

How to Inject Yourself

All insulin injections should be made into your fat, not into your muscles or veins.  Injecting yourself in a vein or a muscle will cause the insulin to be absorbed too quickly, which will cause an episode of hypoglycemia (very low blood sugar).  Injecting into a muscle would also be much more painful than injecting into fat.

Do not inject insulin near a mole, near scars, or into skin that has a rash or any kind of dermatitis.

You should move your injection site by at least one-half inch every time so that you do not inject in the same spot more than once every two to four weeks.  If a previous shot left a bruise, do not inject in that spot again until the bruise heals.

If you have a large belly, you may have developed large veins in your fat.  In that case, it's not a bad idea to palpate (feel) any location where you intend to inject yourself.  if you feel a lump that compresses under your finger, it is most likely a large vein, and that area should be avoided.

Some insulins, most notably mixtures of R and NPH, must be shaken before injecting.  The best way to "shake" insulin is to rotate the vial gently 10 to 20 times.  Hard shaking will cause bubbles to form, and some people think that it may cause the insulin to degrade.

It is not necessary to swab the injection site with alcohol if you believe your skin is clean, but doing so may reduce any possibility of infection (infections from shots are rare to nonexistent).  However, if you are injecting close to your groin area, swabbing is a good idea because there are more bacteria in the groin.  If you use a swab, swab the top of the insulin vial before swabbing your skin.

Do you need to wash your hands first?  It certainly can't hurt to do so, especially if you haven't washed them in a while.  If you don't touch the spot where you are going to inject, and if you don't touch the needle, you aren't likely to hurt yourself if your hands aren't absolutely clean.

Pull the plunger on your syringe to draw some air into it.  Specifically, if you are taking a shot of 20 units, draw 20 units of air into the syringe.  With the vial right side up, insert the needle in the top of the insulin vial and press the plunger to expel the air in the syringe.  With the needle still in the vial, turn the vial and needle upside down and gradually pull the insulin into the syringe using the plunger.  If air bubbles get into the syringe, push the insulin back into the vial and start pulling again.  You may find that it is impossible to avoid all air bubbles, but a small bubble will not hurt you as long as you do not inject the insulin into a vein.

If you are mixing insulins, insert the needle into the second vial and draw in whatever amount you need.  If you are mixing R with NPH or 70/30, draw the R in first.

You should inject yourself in a pad of fat that is at least one inch thick.  Aim the syringe at your fat and insert it quickly from two or three inches away, being careful to insert the needle straight.  A quick insertion of the needle will be less painful than a slow insertion.  Modern needles are very short and thin, and you may not feel any sting at all.  The amount of sting you feel may vary from one spot to the next, depending on whether you hit a nerve.

If you are slender and can't find a pad of fat that is one inch thick, then insert the needle sideways so that the insulin is injected right under the skin.  Slender people may also pinch their skin to lift it, though not everyone has skin that is loose enough to pinch.

In addition to the sting of the needle, some people feel a sting as the insulin is pushed in.  Injecting the insulin slowly will minimize the sting.  If the stinging is too great, you can pull the needle out and try another spot.  Some people feel no pain at all from their injections, while some people feel quite a bit of stinging.  A lot depends on whether you hit a nerve when you insert the needle.

If, after injecting yourself, a small bubble of blood or insulin emerges, just wipe it away.  If a hard lump forms at the injection site, that means that a small pool of blood has collected under the skin.  Your body will absorb the blood.

If a bruise develops at the injection site, there is no need to be concerned.

Do not reuse syringes; the small amount of insulin remaining in the used syringe may cause the insulin in the vial to polymerize (i.e., lose its potency).

Painless Injections

Richard Bernstein, M.D., the great pioneer in the field of diabetes who wrote the book The Diabetes Solution, claims that insulin shots are painless now that needles are so small.  That isn't true.  Bernstein started injecting himself at a time when needles were large, so today's needles may seem painless by comparison.  Whether or not a shot is painless depends on whether you hit a nerve with the needle.  Also, as the insulin is going in, it can put pressure on a nerve, or even tear a nerve.  Furthermore, as time passes and you continue to inject in your stomach area, your stomach may become sensitized to the shots, meaning that the pain will increase over time.  However, the pain will never be more than a strong sting, and on many occasions the sting will be very mild.  The good news is that you get used to it.  Whatever phobia you have about needles will subside after a month or so, and injecting will become routine.

Injection Methods to Avoid

You may have heard that throwing the syringe at your fat is the quickest and least painful way to inject, but it is doubtful that anyone does that.  First, you may have difficulty throwing the syringe straight in, especially if you are throwing it at your belly.  Second, fat is not rigid, and the moment the needle enters your fat, the syringe will likely flop to one side, which could be painful.

Some diabetics who make multiple small injections to maintain tight control of their blood sugar may make injections through their clothes.  However, injecting through your clothes does not allow you to see if you are injecting into a blemish or a bruise.  It is also conceivable that the needle could pull a thread into your fat, though that would probably not harm you.  In addition, if a bubble of blood emerges from the injection site, your clothes would be stained.  Injecting through your clothes is a bad idea.

Where to Inject

The best places to inject are:

- your belly under the ribs (avoid the area around the navel, which has more blood vessels and nerves)
- your hips
- the sides of your upper thighs if they are fatty (the front of your thighs may be painful)
- your upper buttocks (if others are injecting your insulin for you)
- the underside of your upper arms, if they are very fatty

The belly is undoubtedly the best place to inject.  It is large enough to rotate your shots.

It is best not to exercise or sit on the area where you make your injection for at least an hour.

What Kind of Syringe to Use

You will probably start out using disposable syringes.  The smallest needles currently available are 6mm long and 31 gauge thick (the larger the gauge number, the thinner the needle).  (6mm needles became available in 2013; before that, 8mm needles were the shortest available.  Not all manufacturers are making the 6mm needles.)  You should use the shortest needle you can find, as recent research has shown that longer needles may enter the muscle (but this is only true if you are slender or injecting in an area which is not fatty).  A 4mm needle is best, but such short needles are only available in reusable, pre-filled insulin "pens", which come with only specialized kinds of insulin in them, so you may have to settle for a 6mm needle.  Most people have enough fat in their bellies to use 6mm needles without cause for concern.

The syringe should hold 30 units, 50 units or 100 units of insulin, depending on the size of your injections.  BD is a good brand of syringes, and they make the 6mm needles.  Easy Touch syringes are less expensive, but -- in this author's experience -- seem to be more painful.  Easy Touch does not make 6mm needles as of early 2014.  Reli-On syringes, sold at Walmart, appear to be the same syringes sold under the BD brand, but they are much cheaper.  Some states require a prescription for syringes, but the majority do not.

How to Handle Your Insulin

Insulin should be kept between 38 and 50 degrees (Fahrenheit).  It is best to store it in a warm part of the refrigerator, such as the door.  If it freezes, it will lose all its potency.  Insulin will probably not lose any potency if its temperature is allowed to rise to 70 degrees or so for short periods, but it shouldn't be stored at room temperature.  If insulin is allowed to rise above 80 degrees, it may lose some or all of its potency, depending on how warm it gets and for how long.

If you are travelling with your insulin, you should keep it in an insulated case (and in a special cold case if you are travelling during the summer).

Once a vial of insulin has been opened, it will last about 45 days before losing its potency (regardless of the expiration date on the vial).  Indeed, manufacturers of insulin generally say that it should be discarded after 28 days, but in actual practice it will last longer.  If you are injecting very small amounts of insulin, you may end up having to throw some of it away.

Where to Buy Your Insulin

If you do not have insurance, Walmart has the lowest prices for insulin.  As of this writing (early 2014), the price at Walmart is about $25 for a vial of Regular, NPH and 70/30 (at most other pharmacies, you can expect to pay $70-$80).  In most states, older insulins such as Regular and NPH do not require a prescription, although some pharmacies may insist on one.  Mixes of those older insulins (such as 70/30) may also be available without a prescription.  Lantus, Levemir and other engineered insulins (also called "insulin analogues") require a prescription in all states.

Keeping a Diary

You will have the greatest success if you keep a diary in which you record the foods you have eaten, your carbohydrate intake, your blood-sugar numbers, and the times and sizes of your injections.  The diary will allow you to see patterns and to make adjustments to your regimen.

Dealing with a "Hypo"

"Hypo" is an informal term that refers to an episode of hypoglycemia (very low blood sugar).  If you accidentally inject your insulin into a vein or muscle, the insulin will enter your system rapidly, and -- depending on the size of the injection -- your blood sugar may fall to dangerously low levels (sometimes low enough to cause unconsciousness).  As your blood-sugar drops, your body will release epinephrine (adrenaline) to alert you that something is wrong.  The epinephrine will cause you to sweat, and it will make your heart pound.  You may also feel weak or faint.  If you experience these symptoms within 45 minutes of taking an insulin shot, do this:

- Immediately eat a glucose tablet or a SweeTart candy (SweeTart candies are mostly dextrose, which is the same thing as glucose).  Take two tablets or candies if your insulin shot was 20 units or more.  If you don't have either of those tablets, eat a half-teaspoon of sugar.

- Test your blood sugar to see how low it is.  If it is very low, take additional tablets and/or sugar (not many tablets are needed).

- Wait ten or fifteen minutes and then test your blood sugar again.  If it is very low, take more tablet(s) and then test your blood again ten or fifteen minutes later.

- Continue to do this -- testing your blood and taking tablet(s) -- every ten or fifteen minutes until your blood sugar normalizes.  You should do this for at least an hour.

- If you took your shot in preparation for a meal that contains carbohydrates, by all means eat the meal.

Note:  When testing your blood sugar on your arm, there is a 15-20 minute delay.  In other words, the reading that you get on your arm at this moment represents what your blood sugar was about 15 minutes ago.  This can complicate matters when you are recovering from a hypo.  You may end up over-compensating and drive your blood sugar too high.

During a hypo, it is not necessary to eat food or take sugar tablets until your symptoms (sweating and heart-pounding) disappear.  That's because it will take longer for the epinephrine to leave your system (about an hour) than it will take for your blood sugar to normalize.  In fact, if you follow the procedure above, you can normalize your blood sugar within 30 minutes or so, but the symptoms will continue until the epinephrine is gone.  It is the low blood sugar that may harm you, not the epinephrine.

A heavy dose of epinephrine can be exhausting, and you may find that you need to take a nap or go to bed early if the hypo occurred in the evening.

Ironically, you may have to take an additional insulin shot in a day in which you have a hypo.  The shot which flooded into your system and caused the hypo was wasted.  If you eat more food, you'll need to take an additional shot to cover that food.  If you over-compensated with sugar or food after the hypo, your blood sugar may have risen too high, and you'll need another shot to normalize your blood sugar.

It is strongly recommend that you mark the spot where you injected the insulin that caused your hypo, as there is probably a large vein in that spot.  Use a black Sharpie pen, and refresh the mark after you shower.  (Of course, if you didn't mark the spot when you first took the shot, you may not remember where it is.)  You should also mark the same spot on the opposite side of your belly, since veins tend to be symmetrical.