What is diabetes?
Diabetes is a set of related diseases in which the body cannot regulate the amount of sugar (specifically, glucose) in the blood.
What are the types of diabetes?
The related diseases of diabetes include:
- Type 1 diabetes
- Type 2 diabetes
- Gestational diabetes
- Prediabetes
- Metabolic syndrome (syndrome X)
- Insulin resistance (a condition that precedes the development of type 2 diabetes)
What are the symptoms of diabetes?
Symptoms of diabetes include:
- Increased urine output
- Excessive hunger
- Urinary tract infections (UTIs)
- Unexplained weight loss
- Excessive thirst
- Excessive urination
- Excessive eating
- Poor wound healing
- Some types of infection
- Altered mental status
- Blurry vision
- Fatigue

QUESTION
Diabetes is defined best as... See AnswerWhat are examples of insulin preparations available?
Insulin preparations
- Examples of rapid acting insulin
- Apidra (insulin glulisine): Supplied in a cartridge, vial, prefilled pen (Solostar)
- Novolog (insulin aspart): Supplied in a cartridge, vial, prefilled pen (FlexPen)
- Humalog: (insulin lispro): Supplied in a cartridge, vial, prefilled pen (Kwik Pen)
- Examples of short acting insulin
- Novolin R, Humulin R (regular insulin): Supplied in a vial
- Velosulin (insulin with a phosphate buffer): Supplied in a pump device
- Examples of intermediate acting insulin
- Humulin N, Novolin N (NPH): Supplied in a vial, pen (Humulin N pen)
- Examples of long acting insulin
- Lantus (insulin glargine): Supplied in a vial, cartridge (OptiClick), prefilled pen (Solostar)
- Levemir (insulin detemir): Supplied in a vial, prefilled pen (FlexPen)
- Tresiba (deglutec injection): Supplied in a vial
For what type of diabetes is insulin prescribed?
Indications for insulin
- Type 1 diabetes
- Type 2 diabetes
- Insulin resistance
- Diabetic ketoacidosis (DKA)
- Gestational diabetes
- Diabetes treatment during pregnancy
What are the side effects of insulin?
Common Side Effects | Frequency | Serious | Frequency |
---|---|---|---|
Hypoglycemia | >40% | Severe hypoglycemia | n/a |
Headache | 12% to 35% | Allergic reactions | n/a |
Flu-like symptoms | 13% | Anaphylaxis | n/a |
Weight gain | 33% | Hypokalemia | n/a |
Lipoatrophy | n/a | ||
Itching | n/a | ||
Rash | n/a | ||
Injection site reaction | n/a | ||
* n/a = not available |
What is the dosage and how is insulin administrated?
Dosage and Administration of insulin
- A meal should be consumed within 30 minutes after administering regular insulin
- Insulin usually is administered by subcutaneous injection into the abdominal wall, thigh, buttocks (gluteal region), or upper arm. Injection sites should be rotated within the same region.
- Some insulins (for example, regular insulin) also may be administered intravenously.
- The dose is individualized for each patient.
- A combination of short or rapid-acting and intermediate or long-acting insulin typically are used
- Some patients may develop insulin resistance and require increasing doses.
- Multiple daily insulin injections or continuous subcutaneous infusions via a pump closely mimic pancreatic insulin secretion.
- Insulin sliding scales (doses of insulin that are based on the glucose level ) may be used for managing critically ill hospitalized patients.
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What are the contraindications, warnings, and precautions for insulin?
Contraindications
- Hypoglycemia (low blood sugar)
- Hypersensitivity to insulin or its excipients (inactive co-ingredients)
Warnings and Precautions
- Hypoglycemia may occur and is the most common side effect of insulin treatment.
- Severe, life-threatening allergic reactions, including anaphylaxis, may occur.
- Hypokalemia (low blood potassium) may occur because insulin stimulates the movement of potassium from the blood into cells. Combining insulin with potassium-lowering drugs may increase the risk of hypokalemia.
- Hepatic (liver) impairment may reduce insulin requirement.
- Renal (kidney) dysfunction may reduce the insulin requirement.
- Illness, emotional disturbance, or other stress may alter the insulin requirement.
- Intravenous administration increases the risk of hypoglycemia and hypokalemia.
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Which drugs interact with insulin?
Insulin Drug Interactions
Drug or Drug Class | Effect | Recommendation |
---|---|---|
Beta-blockers (for example, propranolol [Inderal, Inderal LA, Innopran XL], atenolol [Tenormin]) | Beta-blockers may mask symptoms of hypoglycemia or prolong hypoglycemia and alter glucose metabolism | Avoid combination if possible |
repaglinide (Prandin) | Increased risk of hypoglycemia and heart attack (myocardial infarction) | Avoid combination if possible |
rosiglitazone (Avandia) or rosiglitazone combination products | Increased incidence of hypoglycemia, fluid retention, ischemia (manifest by angina or heart pain), congestive heart failure | Avoid combination if possible |
Thiazides and thiazide combination products | Hyperglycemia; may reduce the effect of insulin | Monitor glucose levels and adjust accordingly |
Corticosteroids | Hyperglycemia; may reduce the effect of insulin | Monitor glucose levels and adjust accordingly |
Estrogens | Hyperglycemia; may reduce the effect of insulin | Monitor therapy and adjust as needed |
levofloxacin (Levaquin) and other fluoroquinolones | Increased risk of hypoglycemia or hyperglycemia | Use with caution, monitor therapy |
Monoamine oxidase inhibitors (MAOIs) | MAIOs may increase insulin secretion. The combination increases the risk of prolonged hypoglycemia. | Monitor glucose levels and adjust accordingly |
Sulfonylureas | Increased risk of hypoglycemia and | Monitor glucose levels and adjust accordingly |
Thyroid hormones | Thyroid hormones may increase insulin requirement | Monitor glucose levels and adjust accordingly |
Yohimbe | Yohimbe may increase the risk of hypoglycemia | Caution is advised |
How well does insulin treat diabetes?
Efficacy of insulin
- In a 24-week study of patients with type 1 diabetes, regular human subcutaneous insulin (mean dose = 18.3 IU) before breakfast and dinner plus human insulin isophane suspension twice daily (mean dose = 37.1 IU) reduced HbA1c by 0.4% from baseline and fasting glucose by -6 mg/dl.
- In a 24-week study of patients with type 2 diabetes, regular human subcutaneous insulin (mean dose = 25.5 IU) before breakfast and dinner plus human insulin isophane suspension twice daily (mean dose = 52.3 IU) reduced HbA1c by 0.6% from baseline and fasting glucose by -6 mg/dl.
What is the mechanism of action (how it works) for insulin?
Pharmacology (mechanism of action) of insulin
Insulin is a hormone secreted by the pancreas. It regulates the movement of glucose from the blood into cells. Insulin lowers blood glucose by stimulating peripheral glucose uptake primarily by skeletal muscle cells and fat, and by inhibiting glucose production and release by the liver. Insulin inhibits lipolysis (breakdown of fat), proteolysis (breakdown of proteins), and gluconeogenesis (manufacture of glucose). It also increases protein synthesis and the conversion of excess glucose into fat. Insulins used to treat diabetes are pharmacologically similar to the naturally produced hormone. Patients with diabetes are insensitive to insulin and do not produce enough insulin which leads to hyperglycemia and symptoms of diabetes. Exogenous insulin preparations replace insulin in diabetics, increasing the uptake of glucose by cells and reducing the short and long-term consequences of diabetes.
Summary
There are a variety of types and preparations of insulin for the treatment of type 1 and type 2 diabetes, gestational diabetes, diabetes during pregnancy, metabolic syndrome, and insulin resistance. Human insulin preparations and regular insulin are made by recombinant DNA technology. Examples of preparations of insulin include rapid acting insulin (Apirda, Novolog, Humalog), short acting insulin (Novolin R, Humulin R), intermediate acting insulin (Humulin N, Novolin N, and long lasting insulin (Lantus, Levemir). Common side effects of insulin include hypoglycemia, headache, weight gain, rash, itching, flu-like symptoms, lipoatrophy, and reaction at the site of injection. Warnings, precautions, and drug interactions should be reviewed prior to taking insulin.
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Related Disease Conditions
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Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include: ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease. ARF: Acute renal (kidney) failure cap: Capsule. CPAP: Continuous positive airway pressure. A treatment for sleep apnea. DJD: Degenerative joint disease. Another term for osteoarthritis. DM: Diabetes mellitus. Type 1 and type 2 diabetes HA: Headache IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis JT: Joint N/V: Nausea or vomiting. p.o.: By mouth. From the Latin terminology per os. q.i.d.: Four times daily. As in taking a medicine four times daily. RA: Rheumatoid arthritis SOB: Shortness of breath. T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
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Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
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Type 2 Diabetes
Type 2 diabetes is a chronic condition that may be reversible with diet and lifestyle changes. Symptoms include excessive thirst, frequent urination, weight loss, fatigue, and an unusual odor to your urine. Most people don't know they have type 2 diabetes until they have a routine blood test. Treatment options include medications, a type 2 diabetes diet, and other lifestyle changes.
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Insulin Resistance
Insulin resistance is the diminished ability of cells to respond to the action of insulin in transporting glucose (sugar) from the bloodstream into muscle and other tissues. There are no signs or symptoms of insulin resistance. Causes of insulin can include conditions such as stress, obesity, metabolic syndrome, and steroid use. Some of the risk factors for insulin resistance include fatty liver, heart disease, strokes, peripheral vascular disease, high cholesterol, and smoking. Treatment for insulin resistance are lifestyle changes and if necessary, medication.
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Diabetes Treatment: Medication, Diet, and Insulin
The major goal in treating diabetes is controlling elevated blood sugar without causing abnormally low levels of blood sugar. Type 1 diabetes is treated with: insulin, exercise, and a diabetic diet. Type 2 diabetes is first treated with: weight reduction, a diabetic diet, and exercise. When these measures fail to control the elevated blood sugar, oral medications are used. If oral medications are still insufficient, insulin medications are considered.
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Diabetic Ketoacidosis
Diabetic ketoacidosis (DKA) is a complication of type 1 diabetes that is life threatening. If a person thinks they may have diabetic ketoacidosis they should seek medical care immediately. Diabetic ketoacidosis happens when a person's insulin levels in the blood become dangerously low. Symptoms of diabetic ketoacidosis include dehydration, abdominal pain, confusion, and nausea and vomiting. Diabetic ketoacidosis needs medical treatment. It cannot be treated at home.
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Diabetes Symptoms in Men
Early symptoms of diabetes are different in men, such as low testosterone. In many cases, prediabetes that will progress to type 2 diabetes if it is not treated early.
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Type 1 vs. Type 2 Diabetes: Differences
Diabetes mellitus is a metabolic condition in which a person's blood sugar (glucose) levels are too high. Over 29.1 million children and adults in the US have diabetes. Of that, 8.1 million people have diabetes and don't even know it. Type 1 diabetes (insulin-dependent, juvenile) is caused by a problem with insulin production by the pancreas. Type 2 diabetes (non-insulin dependent) is caused by: Eating a lot of foods and drinking beverages with simple carbohydrates (pizza, white breads, pastas, cereals, pastries, etc.) and simple sugars (donuts, candy, etc.) Consuming too many products with artificial sweeteners (We found out that they are bad for us!) Lack of activity Exercise Stress Genetics While the signs and symptoms of both types of diabetes are the same, which include: Increased urination Increased hunger Increased thirst Unexplained weight loss. However, the treatments are different. Type 1 diabetes is insulin dependent, which means a person with this type of diabetes requires treatment with insulin. People with type 2 diabetes require medication, lifestyle changes like eating a healthy diet, and getting regular exercise.
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What Is a High Insulin Level?
Insulin is a hormone (a chemical substance that acts as a messenger in the human body) that is secreted by an abdominal organ called the pancreas. High insulin levels are levels of the hormone that are higher than they should be after ingesting glucose.
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Diabetic Diet
A diabetic diet, or diabetes diet helps keep blood glucose levels in the target range for patients. Exercise and medication may also help stabilize blood glucose levels. Keeping track of when you take your diabetic medicine, keeping track of food choices, eating the proper amount of fruits, vegetables, carbohydrates, and fats will also help maintain proper blood glucose levels.
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Which is Worse - Type 1 or Type 2 Diabetes?
Learn about the similarities and differences between Type 1 and Type 2 Diabetes.
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Type 1 Diabetes (Symptoms, Causes, Diet, Treatment, Life Expectancy)
Type 1 diabetes mellitus (juvenile) is an auto-immune disease with no known cause at this time, although there are a few risk factors. Symptoms of type 1 diabetes include frequent urination, unintentional weight loss, dry and itchy skin, vision problems, wounds that heal slowly, and excessive thirst. Type 1 diabetes is diagnosed with blood tests. A healthy lifestyle and controlling blood glucose levels can improve life expectancy.
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Gestational Diabetes (Diabetes during Pregnancy))
Learning how to avoid gestational diabetes is possible and maintaining a healthy weight and diet before and during pregnancy can help. Discover risk factors, tests and treatments for, and signs and symptoms of gestational diabetes.
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Metabolic Syndrome
The main features of metabolic syndrome include insulin resistance, hypertension (high blood pressure), cholesterol abnormalities, and an increased risk for clotting. Patients are most often overweight or obese. Lifestyle modification such as the Mediterranean diet, exercise, and quitting smoking are the preferred treatment of metabolic syndrome.
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Diabetes Foot Problems
Diabetes related foot problems can affect your health with two problems: diabetic neuropathy, where diabetes affects the nerves, and peripheral vascular disease, where diabetes affects the flow of blood. Common foot problems for people with diabetes include athlete's foot, fungal infection of nails, calluses, corns, blisters, bunions, dry skin, foot ulcers, hammertoes, ingrown toenails, and plantar warts.
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Eye Problems and Diabetes
Diabetes and eye problems are generally caused by high blood sugar levels over an extended period of time. Types of eye problems in a person with diabetes include glaucoma, cataracts, and retinopathy. Examples of symptoms include blurred vision, headaches, eye aches, pain, halos around lights, loss of vision, watering eyes. Treatment for eye problems in people with diabetes depend on the type of eye problem. Prevention of eye problems include reducing blood pressure, cholesterol levels, quitting smoking, and maintaining proper blood glucose levels.
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Drug Allergy (Medication Allergy)
Drug or medication allergies are caused when the immune system mistakenly creates an immune response to a medication. Symptoms of a drug allergic reaction include hives, rash, itchy skin or eyes, dizziness, nausea, diarrhea, fainting, and anxiety. The most common drugs that people are allergic to include penicillins and penicillin type drugs, sulfa drugs, insulin, and iodine. Treatment may involve antihistamines or corticosteroids. An EpiPen may be used for life-threatening anaphylactic symptoms.
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What Are the First Signs and Symptoms of Hypoglycemia?
Hypoglycemia is an abnormally low blood sugar level. It is most common in patients with diabetes mellitus who are taking insulin and skip their meals. Overdosing of insulin can also cause hypoglycemia. Severe hypoglycemia can be life-threatening and fatal. Patients with reactive hypoglycemia have a better chance of improvement with dietary changes. Patients with hypoglycemia should learn to recognize early symptoms to avoid serious complications.
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Can Type 2 Diabetes be Cured?
Type 2 diabetes is a long-term medical condition in which the body is not able to regulate blood sugar (glucose) level because of the inability of the body to properly use insulin. An individual can get type 2 diabetes because of a number of factors that reduce insulin action or quantity in the body. The goals of diabetes management are to eliminate symptoms and prevent the development of complications. Many drugs, both oral and injectable, are available for diabetes management.
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Can Type 1 Diabetes be Cured?
Type 1 diabetes is a disorder of the pancreas. The organ doesn't make enough insulin. Learn what medical treatments can help ease your type 1 diabetes symptoms and speed up your recovery.
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Tips for Managing Type 1 and 2 Diabetes at Home
Managing your diabetes is a full time commitment. The goal of diabetic therapy is to control blood glucose levels and prevent the complications of diabetes. Information about exercise, diet, and medication will help you manage your diabetes better. Blood glucose reagent strips, blood glucose meters, urine glucose tests, tests for urinary ketones, continuous glucose sensors, and Hemoglobin A1C testing information will enable you to mange your diabetes at home successfully.
Treatment & Diagnosis
Medications & Supplements
- How Long Does Insulin Last After Injection?
- Jardiance Side Effects, Warnings, and Drug Interactions
- What Is Intravenous Insulin Therapy?
- Types of Insulin Medications for Diabetes
- insulin glargine (Lantus)
- How Do You Give Intravenous Insulin Therapy?
- Precose (acarbose)
- canagliflozin (Invokana)
- tolazamide (Tolinase brand has been discontinued.)
- Types of Diabetes Type I And II Medications
- Synjardy XR (empagliflozin and metformin extended-release)
Prevention & Wellness
- California's Plan to Make Low-Priced Insulin Could Be Example for Nation
- Americans Are Rationing Insulin Due to High Cost
- California Will Produce Its Own Insulin to Bring Down Prices
- Once-a-Week Insulin for Type 2 Diabetes Shows Promise in Early Trial
- Price Hikes Have Patients Turning to Craigslist for Insulin, Asthma Inhalers
- Medtronic MiniMed 600 Series Insulin Pumps Recalled
- Medicare Could Save Billions If Allowed to Negotiate Insulin Prices
- Light-Activated Insulin-Producing Cells May Lead to New Drug-Free Diabetes Treatment

Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.