Diabetes mellitus is a disorder in which blood sugar (glucose) levels are abnormally high because the body does not produce enough insulin.
InsulinSome Trade Names
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, a hormone released from the pancreas, controls the amount of sugar in the blood. When a person eats or drinks, food is broken down into materials, including sugar, that the body needs to function. Sugar is absorbed into the bloodstream and stimulates the pancreas to produce insulinSome Trade Names
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. InsulinSome Trade Names
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allows sugar to move from the blood into the cells. Once inside the cells, sugar is converted to energy, which is either used immediately or stored until it is needed.
The levels of sugar in the blood vary normally throughout the day. They rise after a meal and return to normal within about 2 hours after eating. Once the levels of sugar in the blood return to normal, insulinSome Trade Names
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production decreases. The variation in blood sugar levels is usually within a narrow range, about 70 to 110 milligrams per deciliter (mg/dL) of blood. If a person has eaten a large amount of carbohydrates, the levels may increase more. People older than 65 years tend to have slightly higher levels, especially after eating.
If the body does not produce enough insulinSome Trade Names
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to move the sugar into the cells, the resulting high levels of sugar in the blood and the inadequate amount of sugar in the cells together produce the symptoms and complications of diabetes.
Doctors often use the full name diabetes mellitus, rather than diabetes alone, to distinguish this disorder from diabetes insipidus, a relatively rare disease that does not affect blood sugar levels (see Pituitary Gland Disorders: Central Diabetes Insipidus).
Types
Type 1: In type 1 diabetes (formerly called insulinSome Trade Names
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-dependent diabetes or juvenile-onset diabetes), more than 90% of the insulinSome Trade Names
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-producing cells of the pancreas are permanently destroyed. The pancreas, therefore, produces little or no insulinSome Trade Names
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. Only about 10% of all people with diabetes have type 1 disease. Most people who have type 1 diabetes develop the disease before age 30.
Scientists believe that an environmental factor—possibly a viral infection or a nutritional factor in childhood or early adulthood—causes the immune system to destroy the insulinSome Trade Names
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-producing cells of the pancreas. A genetic predisposition may make some people more susceptible to the environmental factor.
Type 2: In type 2 diabetes (formerly called non-insulinSome Trade Names
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-dependent diabetes or adult-onset diabetes), the pancreas continues to produce insulinSome Trade Names
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, sometimes even at higher-than-normal levels. However, the body develops resistance to the effects of insulinSome Trade Names
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, so there is not enough insulinSome Trade Names
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to meet the body's needs.
Type 2 diabetes may occur in children and adolescents, but usually begins in people older than 30 and becomes progressively more common with age. About 15% of people older than 70 have type 2 diabetes. Certain racial and cultural groups are at increased risk of developing type 2 diabetes: blacks and Hispanics who live in the United States have a twofold to threefold increased risk. Type 2 diabetes also tends to run in families.
Obesity is the chief risk factor for developing type 2 diabetes, and 80 to 90% of people with this disease are obese. Because obesity causes insulinSome Trade Names
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resistance, obese people need very large amounts of insulinSome Trade Names
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to maintain normal blood sugar levels.
Certain diseases and drugs can affect the way the body uses insulinSome Trade Names
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and can lead to type 2 diabetes. High levels of corticosteroids (from Cushing's disease or from taking corticosteroid drugs) and pregnancy (gestational diabetes (see Pregnancy at High-Risk: Gestational Diabetes) are the most common causes of altered insulinSome Trade Names
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use. Diabetes also may occur in people with excess production of growth hormone (acromegaly) and in people with certain hormone-secreting tumors. Severe or recurring pancreatitis and other diseases that directly damage the pancreas can lead to diabetes.
Symptoms
The two types of diabetes have very similar symptoms. The first symptoms are related to the direct effects of high blood sugar levels. When the blood sugar level rises above 160 to 180 mg/dL, sugar spills into the urine. When the level of sugar in the urine rises even higher, the kidneys excrete additional water to dilute the large amount of sugar. Because the kidneys produce excessive urine, a person with diabetes urinates large volumes frequently (polyuria). The excessive urination creates abnormal thirst (polydipsia). Because excessive calories are lost in the urine, the person loses weight. To compensate, the person often feels excessively hungry. Other symptoms include blurred vision, drowsiness, nausea, and decreased endurance during exercise.
Type 1: In people with type 1 diabetes, the symptoms often begin abruptly and dramatically. A condition called diabetic ketoacidosis may quickly develop. Without insulinSome Trade Names
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, most cells cannot use the sugar that is in the blood. Cells still need energy to survive, and they switch to a back-up mechanism to obtain energy. Fat cells begin to break down, producing compounds called ketones. Ketones provide some energy to cells but also make the blood too acidic (ketoacidosis). The initial symptoms of diabetic ketoacidosis include excessive thirst and urination, weight loss, nausea, vomiting, fatigue, and—particularly in children—abdominal pain. Breathing tends to become deep and rapid as the body attempts to correct the blood's acidity (see Acid-Base Balance: Acidosis). The person's breath smells like nail polish remover, the smell of the ketones escaping into the breath. Without treatment, diabetic ketoacidosis can progress to coma and death, sometimes within a few hours.
Type 2: People with type 2 diabetes may not have any symptoms for years or decades before they are diagnosed. Symptoms may be subtle. Increased urination and thirst are mild at first and gradually worsen over weeks or months. Eventually, the person feels extremely fatigued, is likely to develop blurred vision, and may become dehydrated.
Sometimes during the early stages of diabetes, the blood sugar level is abnormally low, a condition called hypoglycemia (see Hypoglycemia).
Because people with type 2 diabetes produce some insulinSome Trade Names
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, ketoacidosis does not usually develop. However, the blood sugar levels can become extremely high (often exceeding 1,000 mg/dL). Such high levels often happen as the result of some superimposed stress, such as an infection or drug use. When the blood sugar levels get very high, the person may develop severe dehydration, which may lead to mental confusion, drowsiness, and seizures, a condition called nonketotic hyperglycemic-hyperosmolar coma.
Complications
People with diabetes may experience many serious, long-term complications. Some of these complications begin within months of the onset of diabetes, although most tend to develop after a few years. Most of the complications are progressive. The more tightly a person with diabetes is able to control the levels of sugar in the blood, the less likely it is that these complications will develop or become worse.
High sugar levels cause narrowing of both the small and large blood vessels. Complex sugar-based substances build up in the walls of small blood vessels, causing them to thicken and leak. As they thicken, they supply less blood, especially to the skin and nerves. Poor control of blood sugar levels also tends to cause the levels of fatty substances in the blood to rise, resulting in atherosclerosis (see Atherosclerosis) and decreased blood flow in the larger blood vessels. Atherosclerosis is between 2 and 6 times more common in people with diabetes than in people who do not have the disease and tends to occur at younger ages.
Over time, elevated levels of sugar in the blood and poor circulation can harm the heart, brain, legs, eyes, kidneys, nerves, and skin, resulting in angina, heart failure, strokes, leg cramps on walking (claudication), poor vision, renal failure, damage to nerves (neuropathy), and skin breakdown. Heart attacks and strokes are more common among people with diabetes.
Poor circulation to the skin can lead to ulcers and infections, and all wounds heal slowly. People with diabetes are particularly likely to have ulcers and infections of the feet and legs. Too often, these wounds heal slowly or not at all, and amputation of the foot or part of the leg may be needed.
People with diabetes often develop bacterial and fungal infections, typically of the skin. When the levels of sugar in the blood are high, white blood cells cannot effectively fight infections. Any infection that develops tends to be more severe.
Damage to the blood vessels of the eye can cause loss of vision (diabetic retinopathy (see Retinal Disorders: Diabetic Retinopathy). Laser surgery can seal the leaking blood vessels of the eye and prevent permanent damage to the retina. Therefore, people with diabetes should have yearly eye examinations to check for damage.
The kidneys can malfunction, resulting in kidney failure that may require dialysis or kidney transplantation. Doctors usually check the urine of people with diabetes for abnormally high levels of protein (albumin), which is an early sign of kidney damage. At the earliest sign of kidney complications, the person is often given angiotensin-converting enzyme (ACE) inhibitors, drugs that slow the progression of kidney disease.
Damage to nerves can manifest in several ways. If a single nerve malfunctions, an arm or leg may suddenly become weak. If the nerves to the hands, legs, and feet become damaged (diabetic polyneuropathy), sensation may become abnormal, and tingling or burning pain and weakness in the arms and legs may develop (see Peripheral Nerve Disorders: Causes). Damage to the nerves of the skin makes repeated injuries more likely because the person cannot sense changes in pressure or temperature.
Long-Term Complications of Diabetes
Tissue or Organ Affected
What Happens
Complications
Blood vessels Atherosclerotic plaque builds up and blocks large or medium-sized arteries in the heart, brain, legs, and penis. The walls of small blood vessels are damaged so that the vessels do not transfer oxygen normally and may leak Poor circulation causes wounds to heal poorly and can lead to heart disease, stroke, gangrene of the feet and hands, erectile dysfunction (impotence), and infections
Eyes The small blood vessels of the retina become damaged Decreased vision and, ultimately, blindness
Kidney Blood vessels in the kidney thicken; protein leaks into the urine; the blood is not filtered normally Poor kidney function; kidney failure
Nerves Nerves are damaged because glucose is not metabolized normally and because the blood supply is inadequate Sudden or gradual weakness of a leg; reduced sensations, tingling, and pain in the hands and feet; chronic damage to nerves
Autonomic nervous system The nerves that control blood pressure and digestive processes become damaged Swings in blood pressure; swallowing difficulties and altered digestive function, with bouts of diarrhea
Skin Poor blood flow to the skin and loss of feeling result in repeated injury Sores, deep infections (diabetic ulcers); poor healing
Blood White blood cell function is impaired Increased susceptibility to infection, especially of the urinary tract and skin
Connective tissue Glucose is not metabolized normally, causing tissues to thicken or contract Carpal tunnel syndrome; Dupuytren's contracture
The Foot in Diabetes
Diabetes causes many changes in the body. The following changes in the feet are common and difficult to treat.
Neuropathy (damage to the nerves) affects sensation to the feet, so that pain is not felt. Irritation and other forms of injury may go unnoticed; an injury may wear through the skin before any pain is felt.
Other changes in sensation alter the way people with diabetes carry weight on their feet, concentrating weight in certain areas so that calluses form. Calluses (along with dry skin) increase the risk of skin breakdown.
Diabetes can cause poor circulation in the feet, making it more likely that ulcers will form when the skin is damaged and making the ulcers slower to heal.
In addition to the changes in the foot, diabetes can affect the body's ability to fight infections. Therefore, once an ulcer forms, it easily becomes infected; the infection may become serious and difficult to treat, leading to gangrene. People with diabetes are more than 30 times more likely to require an amputation of a foot or leg than are people without diabetes.
Foot care is critical. (see Performing Foot Care) The feet should be protected from injury, and the skin should be kept moist with a good skin moisturizer. Shoes should fit properly and not cause areas of irritation. Shoes should have appropriate cushioning to spread out the pressure caused by standing. Going barefoot is ill advised. Regular care from a podiatrist, such as having toenails cut and calluses removed, may also be helpful. Also, sensation and blood flow to the feet should be regularly evaluated by a doctor.
Diagnosis
The diagnosis of diabetes is made when a person has abnormally high levels of sugar in the blood. Blood sugar levels are often checked during a routine physical examination. Checking the levels of sugar in the blood annually is particularly important in older people, because diabetes is so common in later life. A person may have diabetes, particularly type 2 diabetes, and not know it. A doctor may also check blood sugar levels if a person has increased thirst, urination, or hunger; frequent infections; or signs of any of the complications associated with diabetes.
To measure the blood sugar levels, a blood sample is usually taken after the person has fasted overnight. However, it is possible to take the blood sample after the person has eaten. Some elevation of blood sugar levels after eating is normal, but even after a meal the levels should not be very high. Fasting blood sugar levels should never be higher than 126 mg/dL. Even after eating, blood sugar levels should not be higher than 200 mg/dL.
Doctors can also measure the level of a protein in the blood, hemoglobin A1C (also called glycolated or glycosylated hemoglobin). This test is most useful in confirming the diagnosis in adults in whom the levels of sugar in the blood are only mildly elevated (see Diabetes Mellitus (DM): Monitoring Treatment).
Another kind of blood test, an oral glucose tolerance test, may be performed in certain situations, such as when a doctor suspects that a pregnant woman has gestational diabetes (see Pregnancy at High-Risk: Gestational Diabetes) or in older people who have symptoms of diabetes but normal glucose levels when fasting. However, it is not routinely used for testing for diabetes. In this test, a person fasts, has a blood sample taken to determine the fasting blood sugar level, and then drinks a special solution containing a large, standard amount of glucose. More blood samples are then obtained over the next 2 to 3 hours and are tested to determine whether the level of sugar in the blood rises abnormally high.
Treatment
Treatment of diabetes involves diet, exercise, education, and, for most people, drugs. If a person with diabetes keeps blood sugar levels tightly controlled, complications are less likely to develop. The goal of diabetes treatment, therefore, is to keep blood sugar levels within the normal range as much as possible. Treatment of high blood pressure and cholesterol levels can prevent some of the complications of diabetes as well. A low dose of aspirinSome Trade Names
ECOTRIN
ASPERGUM
taken daily is also helpful.
People with diabetes benefit greatly from learning about the disease, understanding how diet and exercise affect their blood sugar levels, and knowing how to avoid complications. A nurse trained in diabetes education can provide information.
People with diabetes should always carry or wear a medical identification bracelet or tag to alert health care professionals to the presence of diabetes. This information allows health care professionals to start life-saving treatment quickly, especially in the case of injury or altered mental status.
Diet management is very important in people with both types of diabetes. Doctors recommend a healthy, balanced diet and efforts to maintain a healthy weight. Some people benefit from meeting with a dietitian to develop an optimal eating plan.
People with type 1 diabetes who are able to maintain a healthy weight may be able to avoid the need for large doses of insulinSome Trade Names
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. People with type 2 diabetes may be able to avoid the need for all drugs by achieving and maintaining a healthy weight. In general, people with diabetes should not eat much sweet food. They should also try to eat meals on a regular schedule; long periods between eating should be avoided. People with diabetes also tend to have high levels of cholesterol in the blood, so limiting the amount of saturated fat in the diet is important. Drugs may also be needed to help control the level of cholesterol in the blood.
Appropriate amounts of exercise can also help people control their weight and maintain blood sugar levels within the normal range.
Keeping blood sugar levels from getting too high is difficult. The main difficulty with trying to tightly control the levels of sugar in the blood is that low blood sugar levels (hypoglycemia) may occur (see Hypoglycemia). Treatment of hypoglycemia is an emergency. Sugar must get into the body within minutes to prevent permanent harm and relieve symptoms. Most of the time, the diabetic person can eat sugar. Almost any form of sugar will do, although glucose works more quickly than table sugar (typical table sugar is sucrose). Many people with diabetes carry glucose tablets or foil packets of a glucose-containing liquid. Other options are to drink a glass of milk (which contains lactose, a type of sugar), sugar water, or fruit juice or to eat a piece of cake, some fruit, or another sweet food. In more serious situations, it may be necessary for an emergency medical professional to inject glucose into a vein.
Another treatment for hypoglycemia involves the use of glucagon. Glucagon can be injected into the muscle and causes the liver to release large amounts of glucose within minutes. Small transportable kits containing a syringe filled with glucagon are available for people with diabetes to use in emergency situations.
Diabetic ketoacidosis is also a medical emergency, because it can cause coma and death. Hospitalization, usually in an intensive care unit, is necessary. Large amounts of fluids are given intravenously along with electrolytes, such as sodium, potassium, chloride, and phosphate, to replace those lost through excessive urination. InsulinSome Trade Names
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is generally given intravenously so that it works quickly and the dose can be adjusted frequently. Levels of sugar, ketones, and electrolytes are measured every few hours. Doctors also measure the blood's acid level. Sometimes, additional treatments are needed to correct a high acid level. However, controlling the levels of sugar in the blood and replacing electrolytes usually allow the body to restore the normal acid-base balance.
The treatment of nonketotic hyperglycemic-hyperosmolar coma is similar to that of diabetic ketoacidosis. Fluids and electrolytes must be replaced. The levels of sugar in the blood must be restored to normal levels gradually to avoid sudden shifts of fluid into the brain. The blood sugar levels tend to be more easily controlled than in diabetic ketoacidosis, and blood acidity problems are not severe.
Insulin Replacement Therapy
People with type 1 diabetes almost always require insulinSome Trade Names
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therapy, and many people with type 2 diabetes require it as well. InsulinSome Trade Names
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is usually injected; it currently cannot be taken by mouth because insulinSome Trade Names
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is destroyed in the stomach. New forms of insulinSome Trade Names
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, such as a nasal spray and a form that can be taken by mouth, are being tested.
Insulin
InsulinSome Trade Names
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is injected under the skin into the fat layer, usually in the arm, thigh, or abdominal wall. Small syringes with very thin needles make the injections nearly painless. An air pump device that blows the insulinSome Trade Names
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under the skin can be used for people who cannot tolerate needles. An insulinSome Trade Names
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pen, which contains a cartridge that holds the insulinSome Trade Names
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, is a convenient way for many people to carry insulinSome Trade Names
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, especially for those who take several injections a day outside the home. Another device is an insulinSome Trade Names
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pump, which pumps insulinSome Trade Names
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continuously from a reservoir through a small needle left in the skin. Additional doses of insulinSome Trade Names
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can be released at programmed times, or release can be triggered as needed; the pump more closely mimics the way the body normally produces insulinSome Trade Names
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. For some people, the pump offers an added degree of control, whereas others find wearing the pump annoying or develop sores at the needle site.
InsulinSome Trade Names
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is available in three basic forms, each with a different speed of onset and duration of action. Rapid-acting insulinSome Trade Names
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, such as regular insulinSome Trade Names
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, is the fastest and shortest acting. Lispro insulinSome Trade Names
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, a type of regular insulinSome Trade Names
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, is the fastest of all. Rapid-acting insulinSome Trade Names
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is often used by people who take several daily injections and is injected 15 to 20 minutes before meals or just after eating. It reaches its maximum activity in 2 to 4 hours and works for 6 to 8 hours.
Intermediate-acting insulinSome Trade Names
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(such as insulinSome Trade Names
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zinc suspension, lente, or isophane insulinSome Trade Names
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NOVOLIN
suspension) starts to work in 1 to 3 hours, reaches its maximum activity in 6 to 10 hours, and works for 18 to 26 hours. This type of insulinSome Trade Names
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may be used in the morning to provide coverage for the first part of the day or in the evening to provide coverage during the night. Long-acting insulinSome Trade Names
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(such as extended insulinSome Trade Names
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zinc suspension, ultra-lente, or glargine) has very little effect for about 6 hours but provides coverage for 28 to 36 hours.
InsulinSome Trade Names
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preparations are stable at room temperature for months, allowing them to be carried, brought to work, or taken on a trip. InsulinSome Trade Names
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NOVOLIN
should not, however, be exposed to extreme temperatures.
The choice of insulinSome Trade Names
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is complex. The following factors are considered before deciding which insulinSome Trade Names
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is best:
How willing and able the person is to monitor the blood sugar levels and adjust the insulin dosage
How varied the person's daily activity is
How adept the person is at learning about and understanding the disease
How stable the person's blood sugar levels are during the day and from day to day
The easiest regimen to follow is a single daily injection of an intermediate-acting insulinSome Trade Names
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. However, such a regimen provides the least control over blood sugar levels and is, therefore, rarely the best approach. Tighter control may be achieved by combining two insulins—a rapid-acting and an intermediate-acting insulinSome Trade Names
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—in one morning dose. This combination requires more skill, but it offers the person greater opportunity to adjust the blood sugar levels. A second injection of one insulinSome Trade Names
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or both may be taken at dinner or at bedtime. Tightest control is usually achieved by injecting a rapid-acting and an intermediate-acting insulinSome Trade Names
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in the morning and evening along with several additional injections of rapid-acting insulinSome Trade Names
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during the day. Adjustments can be made as the person's insulinSome Trade Names
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needs change. Although this regimen requires the most knowledge of the disease and attention to the details of treatment, it is considered the best option for most people who are treated with insulinSome Trade Names
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.
Some people, especially older people, take the same amount of insulinSome Trade Names
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every day; others adjust the insulinSome Trade Names
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dose daily depending on their diet, exercise, and blood sugar patterns. In addition, insulinSome Trade Names
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needs may change if a person experiences weight changes, emotional stress, or illness, especially infection.
Over time, some people develop resistance to insulinSome Trade Names
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. Because the injected insulinSome Trade Names
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is not exactly like the insulinSome Trade Names
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the body manufactures, the body can produce antibodies to the insulinSome Trade Names
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. These antibodies interfere with the insulinSome Trade Names
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's activity, so a person with insulinSome Trade Names
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resistance must take very large doses.
InsulinSome Trade Names
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injections can affect the skin and underlying tissues. An allergic reaction, which occurs rarely, produces pain and burning, followed by redness, itchiness, and swelling around the injection site for several hours. More commonly, the injections either cause fat deposits, making the skin look lumpy, or destroy fat, causing indentation of the skin. Many people rotate the injection sites, for example, using the thigh one day, the stomach another, and an arm the next, to avoid these problems.
Oral Antihyperglycemic Drugs
Oral antihyperglycemic drugs can often lower blood sugar levels adequately in people with type 2 diabetes. However, they are not effective in type 1 diabetes. There are several types. Sulfonylureas (for example, glyburideSome Trade Names
DIABETA
MICRONASE
) and meglitinides (for example, repaglinideSome Trade Names
PRANDIN
) stimulate the pancreas to produce more insulinSome Trade Names
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(insulinSome Trade Names
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NOVOLIN
secretagogues). Biguanides (for example, metforminSome Trade Names
GLUCOPHAGE
) and thiazolidinediones (for example, rosiglitazoneSome Trade Names
AVANDIA
) do not affect the release of insulinSome Trade Names
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but increase the body's response to it (insulinSome Trade Names
HUMULIN
NOVOLIN
sensitizers). A doctor may prescribe one of these drugs alone or with a sulfonylurea drug. Another class of drug is the glucosidase inhibitors, such as acarboseSome Trade Names
PRECOSE
, which work by delaying absorption of glucose in the intestine.
Insulin Replacement Therapy
Oral antihyperglycemic drugs are usually prescribed for people with type 2 diabetes if diet and exercise fail to lower the levels of sugar in the blood adequately. The drugs are sometimes taken only once a day, in the morning, although some people need two or three doses. More than one type of oral drug may be used if one is not adequate. If oral antihyperglycemic drugs cannot control blood sugar levels well enough, insulinSome Trade Names
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injections alone or in combination with the oral drugs may be needed.
Oral Antihyperglycemic Drugs
Class
Drug
Number of Daily Doses
Selected Side Effects
Biguanides
Metformin 2 to 3 Diarrhea; increased acidity of body fluids (rare); liver failure (rare)
Extended-release metformin 1 to 2
Sulfonylureas
Acetohexamide 1 to 2 Weight gain; low sodium in blood (hyponatremia) with chlorpropamide
Sulfonylureas
Chlorpropamide 1
Glimepiride 1
Glipizide 1 to 2
Glyburide 1 to 2
Micronized glyburide 1 to 2
Tolazamide 1 to 2
Tolbutamide 1 to 2
Meglitinides
Nateglinide 3 Weight gain
Repaglinide 3
Thiazolidinediones
Pioglitazone 1 Weight gain; fluid retention (edema)
Rosiglitazone 1 to 2 Weight gain; fluid retention (edema)
Glucosidase inhibitors
Acarbose 3 Diarrhea; abdominal pain; bloating
Miglitol 3
Monitoring Treatment
Monitoring blood sugar levels is an essential part of diabetes care. People with diabetes must adjust their diet, exercise, and drugs to control blood sugar levels. Monitoring blood sugar levels provides the information needed to make those adjustments. Waiting until symptoms of low or high blood sugar levels develop is a recipe for disaster.
Blood Sugar Measurement
Many things cause blood sugar levels to change: diet, exercise, stress, illness, drugs, and even the time of day. The blood sugar levels may jump after a person eats foods he did not realize were high in carbohydrates. Exercise may cause the levels of sugar in the blood to fall low, requiring that additional sugar be eaten. Emotional stress, an infection, and many drugs tend to increase blood sugar levels. Blood sugar levels increase in many people in the early morning hours because of the normal release of hormones (growth hormone and corticosteroids), a reaction called the dawn phenomenon. And blood sugar may shoot too high if the body releases sugar in response to low blood sugar levels (Somogyi effect).
Blood sugar levels can be measured easily at home or anywhere. Most blood sugar monitoring devices use a drop of blood obtained by pricking the tip of the finger with a small lancet. The lancet holds a tiny needle that can be jabbed into the finger or placed in a spring-loaded device that easily and quickly pierces the skin. Most people find the pricking nearly painless. Then, a drop of blood is placed on a reagent strip. In response to sugar, the reagent strip undergoes some chemical changes. A machine reads the changes in the test strip and reports the result on a digital display. Most of these machines time the reaction and read the result automatically. The machines are smaller than a deck of cards.
A new device reads blood sugar through the skin without needing a sample of blood. The device is worn like a wristwatch and can measure the level of sugar in the blood every 15 minutes. Alarms on the device can be set to sound when blood sugar levels drop too low or climb too high. Disadvantages of this device are that it must be calibrated periodically with a blood test, it may irritate the skin, and it is somewhat large.
Most people with diabetes should keep a record of their blood sugar levels and report them to their doctor or nurse for advice in adjusting the dose of insulinSome Trade Names
HUMULIN
NOVOLIN
or the oral antihyperglycemic drug. Many people can learn to adjust the insulinSome Trade Names
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NOVOLIN
dose on their own as necessary.
Although urine can also be tested for the presence of sugar, checking urine is not a good way to monitor treatment or adjust therapy. Urine testing can be misleading because the amount of sugar in the urine may not reflect the current level of sugar in the blood. Blood sugar levels can get very low or reasonably high without any change in the sugar levels in the urine.
Doctors can monitor treatment using a blood test called hemoglobin A1C. When the blood sugar levels are high, changes occur in hemoglobin, the protein that carries oxygen in the blood. These changes are in direct proportion to the blood sugar levels over an extended period. Thus, unlike the blood sugar measurement, which reveals the level at a particular moment, the hemoglobin A measurement demonstrates whether the blood sugar levels have been controlled over the previous few weeks. The normal level for hemoglobin A is less than 7%. People with diabetes rarely achieve such levels, but tight control aims to come close. Levels above 9% show poor control, and levels above 12% show very poor control. Most doctors who specialize in diabetes care recommend that hemoglobin A1C be measured every 3 to 6 months. Fructosamine, a glycolated amino acid, is also useful for measuring glucose control over a period of a few weeks.
Experimental Treatments
Experimental treatments are also showing promise for the treatment of type 1 diabetes. In one such treatment, insulinSome Trade Names
HUMULIN
NOVOLIN
-producing cells are transplanted into body organs. This procedure is not yet routinely performed, however, because immunosuppressant drugs must be given to prevent the body from rejecting the transplanted cells. Newer techniques may make suppression of the immune system unnecessary.
Last reviewed/revised February 1, 2003
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2006-12-18 15:36:39
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