Category Archive: Insulin
Subcategories: No categories
The Ins and Outs of Insulin
Get to know insulin. All people with type 1 diabetes and many people with type 2 or gestational diabetes use insulin to manage their blood glucose levels.
Since its discovery in the 1920s, scientists have learned a great deal about insulin. They know a lot about how it works in people without diabetes. And they also know that when insulin is absent or doesn’t do its job, people develop diabetes.
Insulin is a hormone. Hormones are chemical signals made by the body that tell various parts of the body how to do their jobs. Some hormones control how the cells in the body grow. Some control how the body uses food and energy to live. And other hormones help muscles to contract, blood to clot, or the heart to beat.
One of insulin’s most important jobs is to help cells use glucose. Insulin acts like a key to unlock the door that lets glucose into the cell. Cells in the body use glucose as a source of energy that they need to live. Without energy, the cells in the body cannot survive. Insulin also helps the body to store extra fuel as fat.
In people with type 1 diabetes, the body does not make enough insulin. This is because most of the cells of the pancreas that make insulin have been destroyed by the immune system. Eventually, all of the cells that make insulin are destroyed and no insulin is produced. That is why type 1 diabetes is also called an autoimmune disorder. People with type 1 diabetes must take injections of insulin in order to live.
In people with type 2 diabetes, insulin is produced, but the cells do not respond to insulin as they should. Glucose has a hard time getting out of the blood and into cells. For some people with type 2 diabetes, diet, exercise, and oral diabetes medication together can help them keep their blood glucose levels on target without insulin injections. But for many people with type 2 diabetes, diet, exercise, and oral diabetes medication are not enough.
Insulin Type
Insulin is a small protein called a polypeptide. It is made up of a chain of small units, known as amino acids. In the early days, only pork and beef insulins were available. These insulins were made from grinding up the pancreases from pigs and cows and purifying the insulin protein. They acted rapidly to lower blood glucose levels. They also were used up rapidly by the body and had to be injected before each meal and at bedtime. Although long-acting animal insulins later became available, the purity and strength of early insulin preparations were not always reliable.
For many years, purified preparations of animal insulins were widely used. However, human insulin is now used most of the time. There is a ready supply of human insulin. It is not harvested from actual pancreases but is made with the help of genetic engineering. The human insulin gene, which tells cells what sequence of amino acids is needed to make the insulin protein, is put into bacteria that multiply rapidly. The bacteria are “tricked” into making human insulin.
Most people who take insulin today use human insulin. Beef insulin is no longer available in the United States and Canada, although pork insulin is. The big advantages to human insulin are that it is easy to make and it is unlikely to cause an allergic reaction. Some people are allergic to animal insulin, because the body sees it as a foreign substance.
Action Times
Premixed Insulin
Insulin Strength
When insulin was first manufactured, different batches often had different strengths. This made it difficult to know how much insulin was needed to lower blood glucose to the right level. Later, the strength of insulin became standardized, but it was available in several different strengths. This often made it confusing to figure out how much insulin to take.
To get the most life out of your insulin supply, keep open bottles “comfortable,” not too hot or too cold. If you’ll use up a bottle of insulin within a month, keep it at room temperature. If it takes longer than a month to use up, it’s best to keep it refrigerated, but warm up the syringe before you inject. Injecting cold insulin can make the injection uncomfortable. Keep unopened bottles in the refrigerator.
Freezing can cause the insulin ingredients to “unmix.” Because insulin is a protein, it will unfold (denature) at temperatures above 86°F, including those reached inside a locked car in the summer.
Today, if you buy insulin in this country, you don’t have to worry about the strength. Nearly all insulin preparations sold in the United States and Canada today are of the same strength: U-100. This means that they have 100 units of insulin in every cubic centimeter (cc) of fluid. U-40, a more diluted insulin, has been discontinued. U-500, a highly concentrated preparation, is available only by special order for people who have developed insulin resistance and need to take extremely high doses of insulin. Hospitals sometimes use U-500 insulin for emergencies.
Insulin syringes also come in different sizes that match the strength of insulin. If you travel outside the United States, bring along sufficient insulin and matching U-100 syringes. You could end up taking the wrong dose if you don’t match insulin strength with the right syringe. If you are planning a long visit outside the country and can’t bring along all the supplies you need, remember that you will need to buy U-40 syringes to use the U-40 insulin found in Latin America and Europe. Ask your provider to help you adjust your dosage.
Buying and Storing Insulin
Using Insulin
Most people with diabetes use a needle and syringe or an insulin pen to take their insulin. Once you learn how, this will be a quick and relatively painless task. If you have problems with your vision or using your hands, there are injection aids that may help solve the problem.
Using a syringe is just one way to take insulin. Advanced delivery systems such as the insulin pump may work better for some people. Some people use an insulin pen, while others use high pressure jet injectors to pass insulin through the skin. Whatever you choose, the basic purpose is the same: to deliver insulin into the fat that lies just under your skin.
Other ways to deliver insulin may become more widely available in the future. Inhaled insulin and insulin patches are being tested. One exciting prospect is an insulin infusion device that is implanted into the body. With this, you might be able to go 2 months without having to worry about refilling it. And scientists hope that one day they will be able to make a device that measures your blood glucose level and delivers the proper amount of insulin automatically.
Injecting Insulin
Coming Soon: Insulin without Injection
Injection Site Rotation
Insulin Pumps
One Shot a Day
A single shot of insulin can sometimes be enough to bring the blood glucose into the target range. Usually, a long-acting insulin such as glargine or intermediate-acting insulin such as NPH is given at bedtime or in the morning. The insulin is used to provide the basal level of insulin. Long-acting insulins provide a steady level of insulin throughout the day and night. Taking intermediate-acting insulin at bedtime helps lower your fasting glucose level. Taking intermediate-acting insulin in the morning provides some coverage for the food you eat as well as basal insulin.
Graph : Typical changes in glucose and insulin levels over 24 hours in someone without diabetes shows what happens during the course of the day for people who do not have diabetes. Graph : One shot of long-acting insulin and Graph : One shot of intermediate-acting insulin show what happens during the course of the day when these insulins are used once a day.
Graph : Typical changes in glucose and insulin levels over 24 hours in someone without diabetes.
As you can see, there isn’t always insulin available from this one injection to provide the bolus of insulin that is needed for meals. Taking one shot a day can also mean that you are more locked into a schedule for your meals. If you take an intermediate-acting insulin, you will need to eat when your insulin is peaking, whether it is convenient or not.
Graph : One shot of long-acting insulin.
Graph : One shot of intermediate-acting insulin.
If you take one shot of long- or intermediate-acting insulin, there are several ways to get the bolus of insulin you need for meals. Some people with type 2 diabetes may be able to make enough insulin to cover the post-meal increase in blood glucose. For these people, providing the basal insulin helps their pancreas to do its job better. Another option is to take oral diabetes medications. These medications can provide the coverage needed for meals. Still another possibility is to take a combination of insulins. You can take a rapid- or short-acting insulin along with your morning shot of NPH insulin. This gives you a bolus of insulin to cover your breakfast meal. You can either use pre-mixed insulins or mix two types of insulin in one injection.
More than One Shot
You may get better coverage by splitting your one shot of insulin into two shots. These can be given in the morning and in the evening. Usually, the morning shot will be a bigger dose than the evening shot. Graph 4 shows the amount of insulin available if you split your intermediate dose into a morning and evening shot. However, you’ll notice that even with this plan, you may have a period in the early morning, between 3 and 10 a.m., when your insulin level may be low.
Graph : Intermediate-acting insulin split into two shots.
One way to improve your coverage is to also mix rapid-or short-acting insulin with each intermediate dose. The rapid-acting or regular insulin provides the mealtime bolus. If you use rapid-acting, the insulin is taken with meals. Doses with regular insulin are taken about 30 minutes before breakfast and dinner, as shown in Graph : Split and mixed regular and intermediate-acting insulin in two shots. As you can see in these graphs, as the rapid-acting or regular insulin decreases, the intermediate insulin starts to work. Just when the intermediate insulin starts to wear off before dinnertime, another mixed dose is given. Again, the rapid-acting or regular insulin kicks in early, and the intermediate insulin picks up the slack to carry you through the night.
Graph : A combination of intermediate- and rapid-acting insulins.
Graph : Split and mixed regular and intermediate-acting insulin in two shots.
It may take a little experimenting and consulting with your health care team to figure out how to best mix rapid-acting or regular and intermediate-acting insulins. The ratio may change until you are getting the results that best suit you. You may find it convenient to buy a premixed insulin, such as a 70/30 or 75/25 mixture. Or you may prefer to split and mix the doses yourself. This lets you change the amounts of rapid-acting or regular and NPH independently of each other. You may find this helpful when trying to account for activity level and food intake.
If you are using a two-shot plan using split and mixed doses of intermediate-acting and rapid-acting or regular insulin, you will need to keep close tabs on your body’s response. This means that you need to monitor your blood glucose levels before and after meals. You may need to monitor at other times as well. A two-shot program gives you better coverage than a single-shot plan but still keeps you closely tied to a regular meal schedule and a regular pattern of activity. This is because you cannot make short-term adjustments in longer-acting insulins. Only rapid-acting or regular insulin can be adjusted immediately to respond to a blood glucose level or change in schedule.
If you find that your blood glucose level is fine at bedtime but high in the morning, you may want to move your evening insulin shot from dinnertime to bedtime. This will make insulin available a little later during the course of the night to keep your glucose levels in range. Make sure that your glucose levels are on target during the evening hours if you try this adjustment.
You may find that you have low blood glucose in the early morning (around 2 or 3 a.m.) with the two-shot plan. If this is the case, think about a three-shot plan. With this, you would give yourself a mixture of rapid- or short-acting and intermediate-acting insulin at breakfast, a rapid- or short-acting insulin at dinner, and an intermediate-acting insulin at bedtime. The insulin levels throughout the day are shown in Graph : Three shots: split and mixed morning dose, rapid-acting dinner dose, and intermediate-acting evening dose.
Graph : Three shots: split and mixed morning dose, rapid-acting dinner dose, and intermediate-acting evening dose.
ADA COMPLETE GUIDE TO DIABETES
The more often you inject insulin, the more opportunities you have to fine-tune your control. You also have more freedom and flexibility with your schedule and food choices. One such plan uses three or four shots a day. A common example is to take rapid-acting insulin before all meals. The dose is based on the carbohydrates eaten at that meal. A long-acting insulin such as glargine provides the basal dose of insulin. The injections of rapid-acting insulin provide the bolus for the three meals. To make this plan work for you, you need to monitor your blood frequently. Then you can adjust the amounts of rapid-acting or regular insulin given before each meal to
■ cover the carbohydrates in your meal;
■ lower a high blood glucose level not sufficiently lowered by the previous rapid-acting injection;
■ anticipate the rise in blood glucose caused by the next meal.
The goal is to keep your blood glucose levels within your target range.
Timing Your Insulin Injections
Knowing when to give your injection, or take your premeal bolus by pump, can be confusing.
| Before breakfast | Before lunch | Before dinner | Before bedtime
Intermediate or long acting |
| Mixture of rapid or short and intermediate acting | |||
| Mixture of rapid or short and intermediate acting | Mixture of rapid or short and intermediate acting | ||
| Mixture of rapid or short and intermediate acting | Rapid or short acting | Intermediate acting | |
| Rapid or short acting | Rapid or
short acting |
Rapid or short acting | Intermediate acting* |
| Rapid or short acting | Rapid or
short acting |
Rapid or short acting | Long acting** |
*The intermediate-acting dose can also be given before dinner.
**The long-acting insulin dose can be taken at bedtime or before dinner or split in half, with half taken before breakfast and half before dinner.
Rapid- and short-acting insulins are taken before meals or very big snacks to counteract the increase in blood glucose that will occur as food is absorbed. Rapid-acting insulins begin to work in about 5-15 minutes. You can take your injection just before you eat. Taking your injection more than 15 minutes before meals can result in a hypoglycemic reaction. Regular insulin takes about 15-30 minutes to start working. If regular insulin is taken too close to the start of a meal, the food will cause blood glucose levels to go too high before the insulin has had a chance to be absorbed for use.
How much in advance of your meal you need to take your regular insulin depends on your blood glucose level before the meal. Try checking about 45 minutes before you plan to start eating. If your blood sugar level is high, you need to inject your regular insulin quickly to help counteract your already high blood glucose level before food sends it even higher. You may also want to postpone your meal for a short time. If your blood sugar level is low, you need to wait to inject regular insulin closer to the time you’ll start eating. Inject at the end of the meal if your blood sugar level is 50 mg/dl or lower. If you can’t check your blood glucose, a general guideline is to take regular insulin 30 minutes before your meal.
Intensive Diabetes Management
Intensive insulin therapy is defined as taking three or more injections a day. But it’s more than just taking shots. It also means more blood glucose checks and spending more time thinking about and caring for your diabetes. So why would you do it? Well, more shots and more monitoring give you more flexibility and spontaneity. It can also keep your blood glucose levels more even and on target. You’ll feel better now and lower your risk for future complications. But is it for you? Ask yourself the following:
Am I unhappy with my blood glucose levels?
- Do my blood glucose checks frequently show unexpected levels, high or low?
- Are my glucose checks frequently out of range?
- Do I have any signs of the complications of diabetes?
- Do I lack the amount of energy I need to participate in all my activities — both day and night?
- Do I want more flexibility in my lifestyle for timing meals, exercise, and other activities?
If you answer “yes” to any of these questions, you may want to investigate the idea of intensive diabetes management. See site for more information.
Action Times
People may respond to preparations of insulin and insulin mixtures differently, so it is important to find the types of insulin that work best for you. Each type of insulin has a different action time, a term that describes the length of time it takes to begin acting and how long its effect lasts. The action times of insulin are due to the following three features:
■ onset: the length of time it takes for insulin to reach the blood and begin lowering blood glucose levels
■ peak time: the time during which insulin is at its maximal strength in lowering blood glucose levels
■ duration: the length of time in which insulin continues to lower blood glucose
Before you got diabetes, your pancreas made the insulin you needed to keep your blood glucose in the normal range. The pancreas made a small amount of insulin throughout the day and night that was released in a steady stream. This is the basal insulin level. When you ate and your blood glucose level began to rise, the pancreas released a burst, or bolus, of insulin.
Insulin doses are planned to work as much like the body as possible. Rapid- and short-acting insulins are bolus insulins. Intermediate- and long-acting insulins are basal insulins. Most people with diabetes take both a basal and a bolus insulin.
| Insulin type | Onset (hours) | Peak (hours) | Duration (hours) |
| Rapid acting
Human lispro or human aspart |
Within 15 minutes | 1 to 2 | 3 to 4 |
| Short acting
Human regular |
0.5 to 1.0 | 2 to 3 | 3 to 6 |
| Intermediate acting
Human NPH Human lente |
2 to 4
3 to 4 |
4 to 10 4 to 12 | 10 to 16 12 to 18 |
| Long acting
Human ultralente Insulin glargine |
6 to 10 2 to 4 | — | 18 to 24 20 to 24 |
The first type of insulin that was made available is known as regular insulin. Regular insulin is short acting and must be injected several times throughout the day. Regular insulin begins working rapidly and is used up fairly quickly by the body. As shown in the table on insulin action times, regular insulin begins to act within an hour. Rapid-acting insulin, lispro insulin and insulin aspart, go to work within minutes. An intermediate-acting insulin, NPH (neutral protamine Hagedorn), contains a molecule known as a protamine, which slows down how fast the body absorbs insulin. Because the insulin reaches the blood more slowly, the onset, peak, and duration times are longer. By using a slower-acting insulin, you can get by with fewer injections each day. For example, a mixture of NPH and regular insulin injected at breakfast can last until dinnertime. You may not need an injection at lunchtime.
People who are allergic to the prota-mine in NPH can consider using lente, another intermediate-acting insulin. An even longer-acting insulin, ultralente, provides a continuous level of insulin with a less pronounced peak. In some people, human ultralente insulin may really act more like an intermediate insulin. Insulin glargine is the newest long-acting insulin. It has no peak and works well with rapid-acting insulin taken before meals. Whenever you change insulins, you need to figure out how quickly the new insulin works in your body.
All insulins used for injections have added ingredients. These prevent bacteria and molds from growing and help keep insulin from spoiling. Intermediate- and long-acting insulins also contain ingredients that prolong their action times. If you think you may be experiencing an allergic reaction to your insulin preparation, talk to your provider.
Signs of a local allergic reaction to insulin:
► dents under the skin at injection sites
► redness at injection sites, either persistent or temporary
► groups of small bumps, similar to hives
► swelling at injection sites
Premixed Insulin
You might be advised to take a mixture of regular or rapid-acting and NPH insulin in one injection. You can mix them yourself. Or you may be able to buy the insulin already mixed. Mixtures of regular and NPH insulins come in various combinations that make them more convenient and easier to handle. For example, you can buy a 50/50 mixture of NPH and regular insulin, or you can buy a mixture that contains 30 percent regular insulin and
Rapid- or short-acting insulins can both be used for bolus doses of insulins. But many people find rapid-acting insulins more convenient.
Rapid-acting insulins can be used by people with either type 1 or type 2 diabetes. The faster action of these insulins makes it easier to time insulin with food. In other words, you can match the rise in blood glucose from food absorption to the rise in insulin in your blood from the rapid-acting insulin.
Rapid-acting insulins are in a form that the body can absorb right away without having to break it down. With regular insulin, the body needs to reduce the insulin protein chain to a smaller size before it can be absorbed and go to work. It can take over 30 minutes from the time regular insulin is injected until it starts working on cells. With rapid-acting insulins, this time is cut in half, so there’s less room for error. It goes to work almost as fast as naturally produced insulin does.
This rapid-acting insulin may give you a lot more flexibility. You can count the carbohydrates in your meal and take insulin to cover that amount. If you eat an extra helping at a meal, you can take care of the carbohydrates with a booster shot right away. You may even be able to wait until you know how much carbohydrate you’ve eaten to inject these insulins. Also, because rapid-acting insulins don’t remain in the body as long as regular insulin does, you may experience fewer episodes of hypoglycemia. Ask your provider whether you could benefit from using a rapid-acting insulin.
| Insulin type | Onset | Peak | Duration |
| Made by body | Immediate, when needed | 30 to 60 minutes | 2 to 3 hours |
| Human lispro, human aspart | Within 15 minutes after injection | 1 to 2 hours | 3 to 4 hours |
| Human regular | 30 to 60 minutes | 2 to 3 hours | 3 to 6 hours |
Crossing time zones can confuse your insulin schedule. You may need to make a new plan for timing your insulin injections. You may also need to adjust your total daily insulin dose. When traveling east, you get a shorter day and need less insulin. When traveling west, you get more hours in a day and need more insulin. Keep your watch on your home time until the first morning after you arrive in a new time zone. Check your blood glucose level more often than usual. For more on insulin and traveling.
70 percent NPH. Preparations containing intermediate- and rapid-acting insulins are also available. Premixed insulins can also be useful for people with eyesight or dexterity problems that make drawing different amounts of insulin from two different bottles difficult. You may want to discuss assistive devices for people with impaired sight with your doctor or diabetes educator.
Even though you can buy mixtures of insulin or can mix them yourself, make sure to talk to members of your health care team before you make any changes in the insulin you take. Never mix types of insulin without the okay from your provider. Mixing insulin with lente or ultra-lente insulin can be more complicated than mixing with NPH. These longer-acting insulins can interfere with rapid-and short-acting insulins and lead to unpredictable results. Rapid-acting and regular insulins are not always readily absorbed by the body when mixed with slower insulins. If your injection schedule calls for taking both regular and lente insulin at the same time, try to inject them immediately after mixing. Glargine cannot be mixed in the same syringe with other insulins. If you have any questions or notice that you don’t get the response you expect from the bolus insulin, talk to your provider. You may need to increase the amount of regular insulin in the mixture or switch to a rapid-acting insulin.
Before you leave your diabetes care provider’s office, be sure you understand the following:
■ what type of insulin you will be taking and the name of the insulin
■ the symptoms of high and low blood glucose that could indicate a problem with your insulin doses
■ where you should inject it
■ whether you need to prepare any mixtures
■ how often to give yourself injections
■ the best times of the day to take your insulin
■ how to store your insulin
Don’t be afraid to take notes or ask questions about anything that’s not clear. Even if you have taken insulin before, you might want to review your insulin schedule on a return visit, especially if you are experiencing any difficulties. You might also want to go over any changes in your schedule that were recommended. Make sure you understand how to time injections with mealtimes. Go step-by-step through a typical day. Also talk about how to adjust for an unusual day. What happens if you oversleep, get sick, travel across time zones, or plan to be unusually active?
Buying and Storing Insulin
Don’t assume that most pharmacies will charge the same price for insulin. The same insulin at one pharmacy or outlet may be several dollars cheaper than that found somewhere else, so it pays to shop around. You might receive a discount for buying certain quantities at your pharmacy or by ordering through the mail. Be sure to ask your pharmacists whether they offer discounts for large orders. Your insurance company or managed care provider may have an agreement with “preferred pharmacies” to offer insulin at reduced rates. Check with your insurance company or managed care provider to see whether it offers this service. By using these services you may be able to keep your costs down. But if you decide to buy insulin in bulk, check the expiration date. You don’t want to buy a big supply of insulin if most of it will expire before you have a chance to use it.
In choosing a pharmacy, convenience may be just as important as cost. You may want a pharmacy that is close by or one that delivers your insulin to you. This can be convenient, especially if you are very busy, ill, or housebound. Also think about the pharmacist. Is the pharmacist easy to talk to? Does he or she seem willing to answer your questions?
Once you find a pharmacy that you like, try to develop a relationship with the pharmacist. Don’t just ask for NPH insulin. Ask questions. Check to make sure you have the desired brand and type. You may want to bring along an empty bottle to make sure you get exactly the same thing each time. Before you pay, double-check to see that you have what you want. If something doesn’t look quite right, or if you are uncertain, be sure to ask your pharmacist.
Storing Insulin
Unopened bottles and unused insulin pens or cartridges
I
Stored in the refrigerator
I
Discard after expiration date on bottle
I
Opened bottles
I
Kept at room
I
Discard after 1 month temperature
You don’t have to worry about storing the bottle of insulin you are using in the refrigerator in between injections. Store unopened bottles of insulin in the refrigerator. The expiration date on a bottle of insulin applies to bottles that have not been opened and have been stored in the refrigerator. If an open vial of insulin is kept at room temperature for more than a month, the insulin may lose some of its strength. Throw away bottles that have been opened for a month and kept at room temperature. If you go through bottles slowly, write the date you first open a bottle on the label so you know when to toss it. Storage guidelines vary from 10 to 28 days for different types of insulin cartridges and prefilled pens. Read the label or package insert or ask your pharmacist or nurse educator if special storage is needed.
One good reason to store the insulin you’re using at room temperature is that injecting cold insulin can make the injection feel more uncomfortable. If your insulin is cold, draw it up into the syringe, then warm it up by gently rolling it back and forth in your hands.
If you are traveling and keep your insulin stored in a cooler, make sure the insulin doesn’t freeze or come in contact with ice.
On the Go with Insulin
Wear a medical ID bracelet or necklace that says you have diabetes.
Don’t get separated from your supplies. Carry your insulin, syringes and/or insulin pump and infusion sets, lancets, glucose meter, blood and ketone test strips, glucagon kit, glucose gel or tablets, and snacks with you. Check with the airlines to meet security requirements.
Some states require a prescription only for lispro, glargine, and aspart. Other insulins are available over the counter, as are syringes. In other states, you need a prescription for all insulins and the syringes. If you are traveling and your insulin is lost or destroyed, ask a pharmacist for help.
Take twice as much insulin and blood testing equipment as you think you’ll need. Getting extra diabetes supplies when you’re away from home can be difficult.
Keep insulin out of direct sunlight and protect it from very hot or very cold temperatures. If flying, keep your insulin supply with you instead of packing it in bags that might get too hot or too cold (such as in an airplane baggage compartment).
Storing insulin at temperatures colder than 36°F can cause it to lose potency and clump. Also avoid getting insulin too hot or leaving it in direct sunlight for too long. Insulin can spoil if it gets hotter than 86°F. The general rule of thumb is, if the temperature is comfortable for you, your insulin will be okay, too. Never use insulin if it looks abnormal. Regular, lispro, aspart, and glargine insulins are clear. If you use clear insulin, always check for any floating particles, cloudiness, or change in color. This could be a sign that your insulin is contaminated or has lost its strength.
Other types of insulin come as suspensions. This means that the material is not completely dissolved, and you might be able to see solid material floating in liquid. However, it should look uniformly cloudy. If you are using NPH or lente, check that your insulin is free of any large clumps of material. Do not use any insulin if you see chunks of material floating around. These changes could mean that crystals or aggregates are forming and the insulin is spoiled or denatured. This can be caused by too much shaking of the insulin bottle or storing insulin at temperatures that are either too hot or too cold.
If you have been instructed to dilute your insulin, use only the diluent recommended by the manufacturer. Properly diluted insulin is good for 2 to 6 weeks stored in the refrigerator.
If you find anything wrong with your insulin right after you buy it, return it immediately. If the condition develops later, try to figure out whether you have handled or stored the insulin the wrong way. If not, talk to your pharmacist about a refund or exchange.
Injecting Insulin
Injecting insulin today is a lot less painful than it used to be. You can choose between disposable syringes with lubricated microfine needles and pen devices. There are many other helpful devices that make injecting with a syringe possible for almost anyone.
Syringes. Today’s smaller gauge needles are slimmer, have sharper points, and are specially coated to slide into the skin smoothly. If you are already using these needles and your injections are still uncomfortable, talk to your diabetes care provider or educator. It often helps to go over your injection technique with them. Trying to relax before injections can help. Tense muscles can make the injection hurt.
Keeping your injection site clean will reduce the risk of developing an infection. But you don’t have to use alcohol to clean your skin before injecting the needle. Soap and water works fine. If you use alcohol before injections, make sure the alcohol dries before you inject, or it could cause stinging. See the Appendix for more tips on injections.
Buying syringes. The syringe consists of a needle, barrel, and plunger. Syringes come in different sizes. It is important to match the size of the syringe to the dose you’ll take with it. You want a syringe that will hold your entire dose of insulin. For example, if you need to take 45 units of insulin, you would want to use a 50-unit syringe to hold all your dose. A 30-unit syringe (the next smallest size) is handy for giving yourself injections of 30 units or less. Likewise, if you need to inject very small doses of insulin, 1/2 unit for example, use syringes that have 1/2 unit marks to keep doses accurate.
Also, check to see whether you can read the markings on your syringe. A 100-unit syringe holds 100 units of insulin in a volume of 1 cc (or 1 ml). Each line marks 2 units of insulin. A 50-unit syringe holds 50 units of insulin in 0.5 cc of liquid, and each line marks 1 unit. A 30-unit syringe holds 30 units of insulin in 0.3 cc, and each line marks 1 unit. You will need to measure out each dose in units. So, if you can’t see the lines marked on the syringe, you will have problems getting an accurate dose. There are devices you can buy to make it easier to read the markings on the syringe. Your pharmacist or diabetes educator can tell you what supplies are available to help you. Another good source of information is the American Diabetes Association Resource Guide published yearly by Diabetes Forecast, the members’ magazine of the American Diabetes Association. The Resource Guide is also available online at www.diabetes.org/diabetes-forecast.jsp and in single copies from the American Diabetes Association.
If you are planning to travel or will be away from home, take along a prescription for syringes. Also ask your provider to write a letter stating that you have diabetes and indicating what type of insulin you use. Some states require a prescription to purchase supplies. If you have problems getting supplies while traveling, try a hospital emergency room.
Reusing syringes. There is no right or wrong answer to the question of whether you should use your insulin syringes over again. It’s really up to you. Reusing syringes can save money.
And it creates less medical waste to litter the environment. There is no evidence that you are more likely to become infected if you reuse a syringe — as long as you follow some safety guidelines. If you choose to reuse syringes, the American Diabetes Association offers guidelines for maintaining them properly.
Most manufacturers of disposable syringes recommend that they be used only once. This is because syringes cannot be guaranteed to be sterile if they are reused. If you have poor personal hygiene, are ill, have open wounds on your hands, or have a low resistance to infection for any reason, you should not reuse syringes. Needles also can become chipped or dull after use. Most needles can be used several times before the tip becomes dull. A dull tip is more painful than a new, sharp needle.
The most important advice about syringe reuse is this: never let anyone use a syringe you’ve already used, and don’t use anyone else’s syringe — ever.
Syringe disposal. How you get rid of your syringe can affect anyone who might come in contact with your trash. This includes the members of your family, neighbors, your trash collector, and people using beaches and other public areas. So it’s important that you do it safely. Never toss a used syringe directly into a trash can. Syringes and lancets and any other material that touches human blood is considered medical waste and must be handled carefully. Before deciding what you will do, you might want to check with your local health department. Some towns and counties have special laws or rules for getting rid of medical waste and may offer safe alternatives. When traveling, if possible, bring your unused syringes home. Pack them in a heavy-duty container, such as a hard plastic pencil box.
Injection Devices. Talk to your doctor or your diabetes educator if you are having problems with any aspects of insulin injection. There are alternatives to injecting by syringe, such as an insulin pen or jet injector. And there are products available that make giving an injection easier. Ask your educator if you can try out some of the insulin-injection aids before you buy anything. This way you can see if any new product is right for you before you invest your money. Be sure to let them know as well if the injections are causing you a great deal of stress or anxiety.
Insulin pens. An insulin pen looks like an ink pen. Instead of a writing tip, it has a disposable needle, and instead of an ink cartridge, there is an insulin cartridge. These pens are popular because they are convenient and accurate in dose. You don’t have to worry about filling syringes or carrying them with you when you are away from home. There are two types of pens. You can buy a pre-filled pen that you throw away once the insulin cartridge is empty. Or you can buy a pen that uses disposable cartridges. A variety of insulins are available in pens and cartridges. You decide the number of units you want, set the injector for that dose, stick the needle in your skin, and inject the insulin. This makes them useful for multiple dose schedules. Pen injectors are conveniently portable because you don’t have to carry around a bottle of insulin. Some are designed to make it easier for people with visual or dexterity problems to give injections.
Each fall, the American Diabetes Association publishes the Resource Guide, a supplement to Diabetes Forecast. You can also buy the guide separately or view it online at diabetes-forecast.jsp. The Resource Guide lists the latest offerings of diabetes tools from manufacturers.
Insertion aids. An automatic injector shoots a needle into your skin. Some automatically release the insulin when the needle hits your skin. With others, you have to press the plunger on the syringe. An automatic injector can be useful if you have arthritis or other problems that make it difficult to hold a syringe steadily. If you cringe at the thought of injecting yourself or don’t like the sight of needles, an automatic injector may be for you.
Jet injectors. Jet injectors push the insulin out so fast that it acts like a liquid needle, passing insulin directly through the skin. If you fear needles or take several injections each day, a jet injector may be a possibility.
The downside is that jet injectors are expensive and may not accurately deliver the insulin dose. Check with your insurer about whether it will cover the cost of this device. Although you will save on the cost of needles and syringes, there may be a hefty initial cost. Ask to test a jet injector before buying. Bruising can be a problem, especially in thin people, children, and the elderly, all of whom have less fat under the skin. Jet injectors also need to be cleaned on a regular basis. Ask your doctor, diabetes educator, and others you know who have used them what they think of jet injectors before deciding.
Aids for the visually impaired. Several products are available that make it easier for people who are visually impaired. These include
■ dose gauges to help you measure your insulin accurately — even mixed doses. Some click with every 1 or 2 units of insulin you measure, and others have Braille or raised numbers.
■ needle guides and vial stabilizers to help you insert the needle into the insulin vial correctly. Some of these will also let you set a desired dosage level.
■ syringe magnifiers that can enlarge the measure marks on a syringe barrel. One model combines a magnifier with the needle guide and vial stabilizer. Another clips around the syringe and magnifies the scale.
Some of these aids only fit certain brands of syringes. Make sure that any aids you purchase will fit the equipment you already have. Some of these aids can be used along with some of the devices discussed above. In addition to injection aids, you can also buy blood glucose meters for the visually impaired.