If you are one of the millions of people with diabetes who has dreamed of a life without needles, several new products are being tested that could put an end to insulin injections. Inhaled insulin, insulin sprayed into the mouth, and insulin in a pill are all being tested. Although none of these products have made it to the marketplace yet, preliminary results are encouraging.

Artificial Pancreas. A device that serves as an artificial pancreas continues to be tested and has been shown to be effective in treating patients with type 1 diabetes. The device consists of a glucose sensor implanted in the abdominal cavity connected to an insulin reservoir. When the sensor detects a rise in blood glucose levels, it triggers a release of insulin from the reservoir, thus functioning much like a healthy pancreas. Preliminary results show that the artificial pancreas is more effective in controlling blood glucose levels than insulin injections alone. The device requires further testing and government approval before making it to the marketplace.

Insulin Pills. Oral insulins are currently being tested in human clinical trials. Because insulin is a protein, it gets degraded in the stomach. But new ways of linking the insulin molecule to polymers allow it to escape digestion and become absorbed into the bloodstream. Preliminary studies are promising. The pills appear to have no adverse side effects and can be taken 15 minutes before a meal.

Insulin Patch. Insulin is normally too big to be absorbed directly through the skin. But a special battery-operated skin patch is being developed that creates microscopic openings in the skin to allow insulin to pass through and into the bloodstream. The patch uses a two-step process to deliver insulin. First, an electronic patch vaporizes cells on the skin surface. A second patch containing a reservoir of insulin is then applied, and the insulin molecules can be absorbed into the bloodstream over a 12-hour period. The delivery system will require government approval before making it to the marketplace. Potentially, the insulin pill and skin patch could be combined to deliver both basal and bolus doses of insulin.

Oral Spray. A new device called Rapid Mist is currently being tested that could deliver an aerosolized version of insulin through the mucus membranes of the cheeks, tongue, and throat. Early results indicate that Rapid Mist, which resembles an inhaler used by people with asthma, is identical to an insulin injection in its ability to lower blood glucose levels.

Inhaled Insulin. Several companies are working on liquid or powdered forms of insulin that are inhaled through the mouth and delivered to the lungs. The insulin then enters the bloodstream as a rapid-acting insulin. The products are being tested for safety and efficacy before making it to the marketplace.

It is usually recommended that you inject your insulin into your abdomen, but you can use other sites as well, as long as you inject into an area that contains fat. Some people find the abdomen easier to use than the thigh. Wherever you choose to inject, you will want to inject at different sites within that area so that you don’t develop problems in and under the skin. You may find that it works best to rotate injection sites within one general area such as the abdomen rather than rotate randomly to sites in different areas of the body. However, some people achieve consistent results by doing all morning injections at one site, such as the buttocks, and all evening injections at a second site, such as the abdomen. You will probably get the most predictable results if you are consistent. That’s because insulin is absorbed at different rates in different body areas. That could cause your body to respond to each insulin injection differently and lead to large fluctuations in blood glucose levels. Injecting in the same general area makes your response to insulin more predictable. Once you have used each injection site within a body area, you can start over in the same body area. There are many opinions on the best way to rotate injection sites. Talk to your diabetes educator about the best method for you.

Typical Injection Sites. Insulin works best when injected into a layer of fat under the skin, above the muscle tissue. Several areas of the body have enough fat tissue under the skin for insulin injection. The abdomen, except for a 2-inch circle around the navel, is used most commonly. Another suitable area is the top and outer thighs. This is best used when you are in a sitting position. The backs of the upper arms, the hips, and the buttocks also work well. Some people, especially those with a large body size, have other options. For example, the lower back can also be a good injection site, as long as there is enough fat under the skin. Wherever you choose to inject, keep these basics in mind:

■ Divide the body area into injection sites about the size of a quarter. Try to make each new injection at least a finger-width away from your last shot. You may need to devise a way to remember where that last site was. For example, you might inject all of your morning shots on the right side and all of your evening shots on the left. When injecting into the arm, use the outer back area of the upper arm, where there is fatty tissue. Avoid the deltoid muscle, the large triangular muscle that covers the shoulder joint. Don’t inject into muscle tissue anywhere in the body. Inject anywhere there is fat on the abdomen except for the 2-inch space around the navel. This has tough tissue that causes erratic insulin absorption.

Avoid injecting too close to moles or scar tissue anywhere on the body.

When injecting in the thighs, shoot for the top and outside areas. If you inject the inner thighs, rubbing between the legs may make the injection site sore. Also avoid the bony area above the knees where there isn’t much fat.

Differences in Insulin Absorption. Most insulins are absorbed most quickly (and at the most consistent speed) when injected into the abdomen, more slowly when injected into the arms, and slower still when injected into the thighs and buttocks.

After you have been injecting insulin into your abdomen for several weeks, you probably know how long it will take for the insulin to take effect. This predictability can help you better manage your blood glucose.

If you were to suddenly switch to injecting insulin into your thigh, you might experience a different response. You might find that it takes longer for your insulin to take effect. Then it would be more difficult to meet your target blood glucose levels without adjusting what time you inject.

Other factors, such as body temperature, diet, exercise, and level of stress, affect your body’s response to insulin. In general, anything that increases the blood flow to an area increases insulin absorption. Your response to insulin could even be the opposite of what you might expect, based on where you inject. For example, playing soccer for 2 hours may cause your insulin to be absorbed more quickly than usual so that your blood glucose level isn’t where you expect it to be. So what can you do? Routinely check your blood glucose level. It is the only way to make sure you are having the response you had planned. Then you’ll know if your site rotation plan is working for you.

Exercise and Injection Sites. Strenuous exercise of muscles near an injection site can make the insulin act more rapidly than normal. This is because there is an increased flow of blood to exercising muscles. That doesn’t necessarily mean that you should stop injecting insulin in the areas of your body you use during exercise. But if you notice that your insulin is peaking faster than you would expect when you exercise, you might want to think about the absorption rate. In general, it’s a good idea to avoid strenuous exercise during the peak action times of your insulin. Insulin plus exercise can lead to a low blood sugar (hypoglycemia).

When you exercise, you have to decide whether to eat more or take less insulin. That’s because exercise and insulin both decrease the amount of glucose in the blood. And you don’t want your blood glucose levels to get too low. Frequent blood glucose monitoring will help you figure out these ups and downs in blood glucose and how to keep things in balance.

Skin Problems and Injection Sites. Two main skin problems can occur at insulin injection sites: lipoatrophy and hypertrophy. With lipoatrophy, fatty tissue under the skin disappears, causing dents in the skin at the injection site. Hypertrophy is the overgrowth of cells, usually fat cells, that makes the skin look lumpy. It can look similar to scar tissue. By rotating the injection site, you can avoid some of these problems. There is also the possibility that some of the problems are caused by the type of insulin you are using.

Lipoatrophy is probably caused by an immune reaction, although its exact cause is not known. Your body is responding to insulin as an injected “foreign” substance. This problem is not common with human insulin. Make sure you are using highly purified insulin, preferably human.

Hypertrophy is not an immune reaction, so you don’t have to change your insulin if you are having this problem. But you do need to change injection sites to avoid this. When the same sites are used over and over again, fat deposits can accumulate in the area. This is also called lipobypertropby. You may be reluctant to change because injections seem less painful in these areas. This can be true because the hypertrophy can numb the area. On the other hand, injections can sometimes be more painful in these areas. The abnormal cell growth can limit the absorption of your insulin. Do not inject into the lumps. Insulin action can be restricted by not being able to move through the tissue. Inject away from the lumps and remember to rotate the sites. Ask a member of your health care team to check your injection sites periodically.

Insulin pumps have come a long way in recent years. These devices are miniature, computerized pumps, about the size of a cell phone, that you can wear on your belt or in your pocket. A pump sends a steady, measured amount of basal insulin through a piece of flexible plastic tubing to a small catheter that is inserted just under the skin and taped in place. This way of delivering insulin is called continuous subcutaneous insulin infusion, or CSII. You can program the pump to send a surge, or bolus, of insulin into your body. You do this just before eating to adjust for the rise in blood glucose that will come as your food digests.

If you use insulin frequently, you have probably thought about getting an insulin pump from time to time. But maybe it seemed too costly or inconvenient. Maybe you didn’t like the idea of being hooked to a machine or changing your diabetes care routine so abruptly. Pumps today weigh less than 4 ounces, so they are easy to wear. You can remove the pump for an hour or two for special occasions and still keep your glucose where you want it. The cost of a pump is high. But with a prescription, and persistence on your part, most insurance companies will pay for all or part of it.

Paying for the Pump. Insulin pumps can cost up to $6,000. Monthly maintenance can run $300 or more, including insulin, infusion sets, and blood testing supplies. If your insurance company will cover them, you’re all set. But some insurance companies won’t pay the start-up or maintenance costs of the pump. What to do?

■ Keep asking! Keep in mind that it took many years, much research, and lots of people asking to convince insurance companies to pay for other therapeutic measures, such as prescription footwear, that have long-term health benefits. Your provider should be your most convincing advocate. He or she may have to write several letters and make several calls to your insurance company with details of your need for the improved glucose levels that are possible on the pump.

■ Ask your diabetes educator to write to your insurance company as well.

■ Work on writing effective, informative letters. All letters should stress how lower glucose levels can mean fewer and less severe diabetes complications in the long run — which is also less expensive for the insurance company in the long run.

How Pumps Work. The pump is a marvel of technology:

■ It beeps if clogged.

■ It lets you know when the batteries run low.

■ It has dosage limits to stop an accidental overdose.

■ You can program it to change the amount of insulin pumped to match your metabolism.

However, insulin pumps are not foolproof. Although they will alert you when a clog stops the flow of insulin, they will not identify a slow flow. Even if you are using an insulin pump, you will still need to monitor your blood glucose frequently.

Pumps use rapid-acting or regular insulin. The insulin is pumped from a filled syringe or cartridge inside the pump through thin plastic tubing to a needle or catheter inserted under the skin. Depending on your insulin needs, the pump can hold a 1- or 2-day supply of insulin. The tubing comes in different lengths, but it is long enough to allow plenty of slack for normal body movement. The insulin pump sends a continuous flow of insulin that trickles through the tube into the injection site at a slow, steady (basal) rate, day and night. The basal rate for pumps can be adjusted from 0.1 to 10 units per hour, depending on your metabolism. Before you eat, you push a button to deliver an extra portion of insulin, called a bolus. You can program, or adjust, the size of the bolus, depending on how much carbohydrate you will be eating in your meal. Delivering a bolus of insulin is just like injecting your premeal shot of insulin when you take multiple injections — without the shot! Usually, you won’t have to take an extra bolus when you eat between meals, unless the snack is large.

Your diabetes care provider or educator will help you calculate your basal and bolus insulin doses. The total basal dose over a day is some percentage of the total daily insulin dose that you’ve been injecting, perhaps 40 to 50 percent. The other 50 to 60 percent of your daily insulin dose is divided into the before-meal bolus doses, most of it at breakfast and dinner, and the remainder at lunch and bedtime. You will need to know how these doses were chosen, so you can learn to adjust them for fine-tuning.

A big advantage to using a pump is that you will have flexible insulin coverage for meals and snacks. You will have to spend a lot of time at the beginning to find the best basal rates, to find out when you need to adjust the basal rate, and to figure out how big a bolus you will need for each meal. You’ll probably want to learn how to estimate the number of grams of carbohydrate in your meals so you can take the needed number of insulin units. This will help you even out your after-meal blood glucose levels. You’ll avoid having big changes in blood glucose levels throughout the day. Eventually, this will lead to a more flexible eating schedule. Pumps still cannot automatically sense your body’s need for insulin. It doesn’t adjust by itself. You still need to take blood glucose readings throughout the day.

Unexplained High Blood Glucose Levels on the Insulin Pump

Have you considered these possibilities?

► The insulin: Is it expired? Has it been exposed to extreme heat or cold? Does it look clumped or filled with particles? Is the vial nearly empty? Have you used it for more than 1 month?

► The insertion site: Have you placed the needle in or near a scar or mole? Near your beltline or other area where there’s friction from clothing? Does the site hurt? Is it red or swollen?

► The infusion set: Did the needle come out? Is insulin leaking around the infusion site? Is there blood or air in the infusion line? Is there a kink in the line? Did the line come loose from the pump? Has the infusion set been in place for more than 2 days? Think about changing the infusion line. The insulin pump: Is the basal rate set correctly? Has the battery run down? Was the cartridge of insulin placed correctly? Is it empty? Was the pump primed with insulin when a fresh cartridge was put in? Is the pump working correctly?

Where will you attach the needle for the insulin pump? Most people choose the abdomen for insulin delivery. This area is convenient to use and gives a reliable, uniform absorption of insulin. How you insert the insulin needle will be different for different brands of infusion sets. With some infusion sets, you use a needle to insert a catheter and then remove the needle, leaving the soft catheter under your skin. With other sets, you insert a short needle. Pumps are easy to remove temporarily because, after clamping the tubing, you can leave the infusion set (the needle and tubing or the soft Teflon catheter) in place. You reattach only the pump. Some infusion sets even have a quick-release feature.

You don’t have to worry that it will hurt when you exercise or if someone bumps into your pump or infusion area. The needle or catheter should be comfortable at all times. If you see any redness or swelling at the infusion site, remove the needle or catheter right away and find a new infusion site. Discuss persistent problems (lasting longer than 24 hours) with your health care team.

Every 1 to 3 days, you’ll need to replace the infusion set and move to a new insertion site. This helps you avoid infection at the insertion site or a clog in the infusion set. Place the new insertion site at least 1 inch away from the last insertion site on the abdomen. Just like with syringes, you need to avoid inserting the needle in scar tissue or moles and use a site rotation schedule.

Using the same insertion site too often or for too long can cause the same skin problems that develop when you don’t rotate your syringe injection sites. Scarring can occur. Check your injection site every day to make sure no insulin is leaking out.

You’ll need to wear the pump almost all the time. If you take the pump off, you’ll need to resume a schedule of insulin injections. However, it is possible for you to take off the pump temporarily, but not for more than 1 to 2 hours. Your blood glucose levels will get high again quickly because you don’t have any insulin. You may want to unhook during lovemaking or other physical activities that can lower blood glucose level. How long you can keep the pump off without an injection depends on how active you are when the pump is off. A dancer might be able to keep it off during an entire performance because exercise lowers blood glucose levels. Through experience and testing, you will figure out how long you can keep the pump off before you need to put it back on or take an insulin injection.

Like all things worthwhile, using a pump successfully takes practice. You will most likely have problems here and there. Perhaps the most common problem is mysterious high blood glucose levels. This occurs quickly when clogged or kinked tubing stops the flow of insulin and pressure builds up in the infusion line. Your pump will sound an alarm if this happens. This is not the only reason for high blood glucose levels. For instance, an infection or inflammation at the insertion site can develop and delay the absorption of insulin. See the box on page 124 for other things to consider when you have unexplained hyperglycemia on the pump.

Should You Use a Pump? Maybe you’re already having trouble sticking to your current testing and injection routine. Then a more intense schedule, such as multiple daily injections or an insulin pump, may not be for you. However, the possible benefits may help you find a new level of commitment.

A major advantage of a pump is that you don’t have to stop what you’re doing to fill a syringe. Your insulin is delivered at the push of a button. You can do this anywhere and at any time. Pumps are also precise. You can set them to pump out as little as one-tenth of a unit (0.1 unit) of insulin per hour.

What are some other reasons for choosing a pump? Maybe you’re planning a pregnancy and want the tightest control possible. Maybe you have to work odd hours at your job and it’s hard enough to balance work, family, and meals during the week without having to adjust to a new injection schedule every weekend. Maybe you have had unwanted swings in blood glucose when injecting intermediate- or long-acting glucose, and you’d like to keep your blood glucose in check. People who want an insulin plan that adapts to day-to-day changes in their lifestyle might like an insulin pump. Making a list of personal advantages and disadvantages may help you decide. One of the most important factors is your level of commitment to this therapy. It does take work — especially at first. But many people find that the added flexibility and improved control are worth it.

Choosing a Pump. There are several insulin pumps on the market today. Your doctor or diabetes educator may prefer one brand over the other. Ask for his or her thoughts on each model. Your best bet may be to talk to other people who use pumps. Find out what they like and what they don’t like about each model. Here are a few things you might want to know:

■ Is it waterproof? Some models are waterproof and can be submerged for up to 30 minutes. Other models are splash proof or water resistant. Check to see whether you can shower, swim, or dive into a pool with the model you want.

■ Can you adjust the basal rate for different times of day? Your pump can alter the rate up to 48 times a day. For example, your basal rate is likely to be greater from

3 a.m. to 7 a.m. than during the rest of the day. All pump manufacturers offer a 24-hour toll-free number. You will want to talk to service people about problems when you suspect the pump isn’t working correctly.

■ What kind of warranty does the manufacturer offer? How often do you have to change the batteries? How easy are the batteries to find, and how expensive are they? Batteries usually last 2 to 4 months.

■ Do you want a pump that will help you calculate doses based on your blood glucose level and carbohydrate intake?

Insulin Plans

How often should you inject insulin? There is no answer that is right for all people at all times. Different plans suit different people, depending on how easily managed your blood glucose levels are and how well you understand the way different foods and physical activity, and even stress, affect your blood glucose levels.

With type 1 diabetes, the pancreas no longer secretes insulin. The goal of insulin therapy is to mimic a normal pancreas as closely as possible. This often requires multiple daily injections of insulin or the use of an insulin pump and frequent blood glucose monitoring.

Type 2 diabetes can cause two different problems. In some people, not enough insulin is produced in relation to how much is needed by the body. Insulin is often needed along with meal planning and exercise. In addition, the cells in the body resist the action of the insulin that is produced. Diet and exercise and oral diabetes medications alone or with insulin may be needed. Therapies for type 2 diabetes may have to take into account both lack of insulin and resistance to insulin. Because their bodies make and release natural insulin, people with type 2 diabetes may be able to manage blood glucose by changing their eating and exercise habits. Others will need oral diabetes medication and still others will need insulin in addition to diet and exercise.

Some women with gestational diabetes manage the high blood glucose levels caused by insulin resistance without insulin therapy. Others need the help of insulin.

Insulin plans can use one, two, or three types of insulin. This means using rapid-acting or regular (short-acting) insulin and, for some people, also using a longer-acting insulin. When deciding on an insulin plan, you and your diabetes care provider will consider how to match your personal goals and needs, both medical and practical, to a combination of insulin type, dose, and schedule. You also need to know when the different injections of insulin are likely to have an effect on your blood glucose levels.

Most insulin plans try to mimic the effects a normal pancreas could produce. A pancreas puts out a steady stream of insulin (a basal or baseline dose) day and night. It also secretes an extra dose of insulin (a bolus) in response to meals. This is the way insulin pumps are usually set up. If insulin injections are preferred, a longer-acting insulin is used to mimic the basal insulin secretion. To substitute for the bolus of insulin, a dose of rapid-acting or regular insulin is usually given before each meal. Which combination of short- and long-acting insulins you use is up to you and your provider. Together, work out a plan that will suit your life and schedule. If your plan is not working out for you, talk to your provider. There are usually many other plans you can try.