insulin regular human

Regular human insulin is a biological product used to treat type 1 and type 2 diabetes. Human insulin is a natural hormone secreted by the pancreas.

Regular human insulin used to treat diabetes is produced in labs using DNA recombinant technology. Animal insulins were used in the past, but currently, the only type of insulin available in the U.S. is human insulin, which is structurally similar to the natural human insulin.

Insulin, released by the pancreas after a meal, regulates the metabolism of carbohydrates, fats and proteins absorbed from food. Reduced insulin secretion or faulty functioning of insulin results in diabetes, a metabolic disorder that impairs the ability of the cells to absorb glucose for energy, resulting in high blood glucose levels (hyperglycemia). Dysfunction of insulin affects the entire body and can damage all organs, particularly, nerves, kidneys, and eyes.

Insulin stimulates the uptake of glucose from blood by all the internal organs, most importantly, the liver, skeletal muscles and fat cells (adipose tissue). In the liver, insulin promotes storage of energy by stimulating conversion of glucose into glycogen and inhibiting glycogen breakdown. It also promotes the synthesis of fatty acids in the liver which are released into the bloodstream for cellular conversion into energy.

In the skeletal muscles, insulin promotes protein and glycogen synthesis, and uptake of glucose and amino acids, the building blocks of proteins. Insulin also promotes energy storage in adipose tissue by stimulating the breakdown of triglycerides into free fatty acids, reducing circulating triglyceride levels in the blood. Insulin level in nondiabetic individuals typically rises after a meal and decreases when blood glucose levels drop to base level.

Regular insulin is administered before mealtimes to enable glucose metabolism and maintain normal glucose levels in patients with type 1 or type 2 diabetes. Insulin is also used to treat complications from diabetes such as severe hyperglycemia and ketoacidosis, a condition with buildup of ketones in blood. Ketone is a type of acid that results when the liver breaks down fats for cellular energy, because the cells are unable to use glucose without insulin.

The types of human insulin used to treat diabetes are categorized by the time taken for onset, peak and duration of insulin effects. Regular human insulins are short-acting insulins with onset of effect in 30-60 minutes, peaking in two to four hours and duration for up to eight hours. Short-acting insulins are known as bolus insulins, which act fast to bring down blood sugar spikes that come with meals. Regular insulin may be administered intravenously in hospitals, with insulin pump implants, or self-administered subcutaneously with needles, pens, or jet injectors.

• Do not use in patients with hypersensitivity to regular human insulin or any of the components in the formulation.
• Do not administer insulin during episodes of hypoglycemia, it can severely reduce glucose levels.
• Glycemic status and insulin requirements in patients may change. Insulin requirements may change during illness, emotional disturbances, or other stressors. Glucose levels must be regularly monitored and insulin regimens appropriately adjusted.
• Changes in insulin regimen can affect glycemic control and cause hyperglycemia or hypoglycemia. Insulin regimen changes should be under close medical supervision with increased frequency of blood glucose monitoring.
• Repeated insulin injections into the same areas can cause skin thickening or depression (lipodystrophy) or abnormal protein clumping in the skin (cutaneous amyloidosis). Injecting in these areas can result in hyperglycemia, and a sudden change in the injection site (to an unaffected area) may result in hypoglycemia.
  • Hypoglycemia is the most common adverse effect with insulins.
  • Hypoglycemia can happen suddenly and symptoms differ in patients and may change over time in the same patient.
  • Prolonged or severe hypoglycemia can cause convulsions, unconsciousness, temporary or permanent brain damage, or even death. 
  • Hypoglycemia risk increases in patients with impaired liver or kidney function.
  • Patients with long-standing diabetes, diabetic nerve disease, recurrent hypoglycemia, or patients taking beta-blockers may have reduced awareness of hypoglycemic symptoms.
• Patients and caregivers must be educated to self-monitor glucose levels, recognize and manage hypoglycemia.
• Insulin can cause severe, life-threatening, generalized allergic reactions including anaphylaxis. Discontinue insulin and monitor the patient until symptoms resolve.
• Insulin causes shift of potassium into the cells and can lead to low blood potassium (hypokalemia), which if untreated, can cause respiratory paralysis and life-threatening irregular ventricular rhythm (ventricular arrhythmia) and death.
• For patients with type 2 diabetes, dosage adjustments in concomitant oral antidiabetic treatment may be needed.
• Concurrent use with thiazolidinediones, a class of oral antidiabetic drugs, can cause dose-related fluid retention and increase the risk for heart failure. Patient should be closely monitored for symptoms of heart failure.

Common side effects of insulin regular human include:

• Hypoglycemia
• Hypokalemia
• Injection site reactions such as:
  • Redness (erythema)
  • Pain
  • Itching (pruritus)
  • Swelling (edema)
  • Depression in skin tissue (lipoatrophy)
  • Thickening of skin tissue (lipohypertrophy)
  • Cutaneous amyloidosis
• Hypersensitivity reactions including:
  • Generalized rash
  • Drop in blood pressure
  • Shortness of breath
  • Wheezing
  • Fast pulse
  • Sweating
• Peripheral edema
• Weight gain

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug.

Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

injectable solution

OTC

• 100units/mL (3mL vial)
• 100units/mL (10mL vial)

Rx

• 500units/mL (20mL vial); prescribe with U-500 syringes to avoid conversion for U-100 tuberculin syringes
• 500units/mL (3mL pen)
• 100units/100mL 0.9% NaCl (Myxredlin)

Adult:

Type 1 Diabetes Mellitus

Indicated to improve glycemic control in patients with diabetes mellitus

Subcutaneous (SC) injection

• Initial: 0.2-0.4 units/kg/day SC divided every 8 hours or more frequently  
• Maintenance: 0.5-1 unit/kg/day SC divided every 8 hours or more frequently; in insulin-resistant patients (e.g., due to obesity), substantially higher daily insulin may be required
• Approximately 50-75% of the total daily insulin requirements are given as intermediate- or long-acting insulin administered in 1-2 injections; rapid- or short-acting insulin should be used before or at mealtimes to satisfy the remaining balance of the total daily insulin requirements
• Premixed combinations are available that deliver rapid- or short-acting components at the same time as the intermediate- or long-acting component

Insulin pump (continuous SC insulin infusion)

• Use appropriate rapid-acting insulin formulation consisting of a combination of basal continuous insulin infusion rate with preprogrammed, premeal bolus doses controlled by the patient
• Conversion from multiple daily SC doses of maintenance insulin: Consider reducing the basal rate to less than equivalent of total daily units of longer acting insulin (e.g., neutral protamine Hagedorn {NPH}); divide total number of units by 24 to get basal rate in units/hour; total units of regular insulin or other rapid-acting insulin formulations should not be included in this calculation

Intravenous IV infusion

• Individualize and adjust dosage based on the individual's metabolic needs, blood glucose monitoring results, and glycemic control goal
• Dosage adjustments may be needed with changes in nutrition, changes in renal or hepatic function or during acute illness

Type 2 Diabetes Mellitus

A type 2 diabetes inadequately controlled by diet, exercise, or oral medication

SC injection

• Suggested beginning dose of 10 units/day SC (or 0.1-0.2 unit/kg/day) in evening or divided every 12 hours
• Morning
  • Give two thirds of daily insulin requirement
  • Ratio of regular insulin to NPH insulin 1:2
• Evening
  • Give one third of daily insulin requirement
  • Ratio of regular insulin to NPH insulin 1:1

IV infusion

• Individualize and adjust dosage based on the individual's metabolic needs, blood glucose monitoring results, and glycemic control goal
• Dosage adjustments may be needed with changes in nutrition, changes in renal or hepatic function or during acute illness

Severe Hyperglycemia/Diabetic Ketoacidosis (Off-label)

• IV regular insulin recommended over SC administration
• 0.1 unit/kg IV bolus (some argue against bolus), THEN  
• 0.1 unit/kg/hour IV continuous infusion; if serum glucose does not fall by 50 mg/dL in the first hour, check hydration status; if possible, double the insulin hourly until glucose levels fall at the rate of 50-75 mg/dL/hour; decrease infusion to 0.05-0.1 unit/kg/hour when blood sugar reaches 250 mg/dL

Hyperkalemia (Off-label)

5-10 units IV insulin in 50 mL D50W (25 g) infused over 15-30 minutes

Dosing Considerations

• Dosage of human insulin, which is always expressed in USP units, must be based on the results of blood and urine glucose tests and must be carefully individualized to optimal effect
• Dose adjustments should be based on regular blood glucose testing
• Adjust to achieve appropriate glucose control

Planning dose adjustments

• Look for consistent pattern in blood sugars for longer than 3 days
• Same time each day: Compare blood glucose levels with previous levels found at that time of day
• For each time of day: Calculate blood glucose range
• Calculate median blood glucose
• Consider eating and activity patterns during the day

Making dose adjustments

• Adjust only 1 insulin dose at a time
• Correct hypoglycemia first
• Correct highest blood sugars next
• If all blood sugars are high (within 2.75 mmol/L [50 mg/dL]): Correct morning fasting blood glucose first
• Change insulin doses in small increments: Type 1 diabetes (1-2 unit change); type 2 diabetes (2-3 unit change)

Sliding scales

• Many sliding scales exist to determine exact insulin dose based on frequent blood glucose monitoring
• Commonly written for every 4 hour blood glucose test
• Sliding scale coverage usually begins after blood glucose is greater than 11 mmol/L (200 mg/dL)
• If coverage is needed every 4 hours for 24 hours, then base insulin dose is adjusted first; sliding scale doses may be adjusted upwards as well

Pediatric:

Type 1 Diabetes Mellitus

• Initial: 0.2-0.4 unit/kg/day SC divided every 8 hours or more frequently  
• Maintenance: 0.5-1 unit/kg/day SC divided every 8 hours or more frequently; in insulin-resistant patients (e.g., due to obesity), substantially higher daily insulin may be required
• Adolescents: May require up to 1.5 mg/kg/day during puberty
• Average total daily insulin requirement for prepubertal children varies from 0.7-1 unit/kg/day but may be much lower

Insulin pump (continuous SC insulin infusion)

• Use appropriate rapid-acting insulin formulation consisting of a combination of basal continuous insulin infusion rate with preprogrammed, premeal bolus doses controlled by the patient
• Conversion from multiple daily SC doses of maintenance insulin: Consider reducing the basal rate to less than equivalent of total daily units of longer acting insulin (e.g., NPH); divide total number of units by 24 to get basal rate in units/hour; total units of regular insulin or other rapid-acting insulin formulations should not be included in this calculation

IV infusion

• Individualize and adjust dosage based on the individual's metabolic needs, blood glucose monitoring results, and glycemic control goal
• Dosage adjustments may be needed with changes in nutrition, changes in renal or hepatic function or during acute illness

Type 2 Diabetes Mellitus

Children younger than 10 years

• Safety and efficacy not established

Children 10 years or older

• Goal is to achieve HbA1C less than 6.5% as quickly as possible by titrating the medications
• Therapy may include once daily intermediate-acting insulin or basal insulin in combination with lifestyle changes and metformin
• Initial treatment with prandial insulin (rapid acting insulin or regular insulin) may be considered in patients failing to achieve glycemic goals with metformin and basal insulin
• Taper once initial goal is reached; transition to lowest effective dose or metformin monotherapy, if possible

IV infusion

• Individualize and adjust dosage based on the individual's metabolic needs, blood glucose monitoring results, and glycemic control goal
• Dosage adjustments may be needed with changes in nutrition, changes in renal or hepatic function or during acute illness

Severe Hyperglycemia/Diabetic Ketoacidosis (Off-label)

• IV regular insulin recommended over SC administration
• Patients with uncomplicated diabetic ketoacidosis and adequate peripheral circulation may be treated with SC rapid acting analogs including insulin as part or lispro when continuous IV regular insulin not possible
• Dextrose (5%) added to normal saline or ½ normal saline should be administered to prevent hypoglycemia after achieving serum glucose levels between 250-300 mg/dL; administer sooner if serum glucose decreases precipitously; may use 10-12.5% dextrose if necessary
• Administer 0.05 to 0.1 units/kg/hour until resolution of ketoacidosis (pH greater than 7.3; bicarbonate greater than 15 mEq/L and/or closure of anion gap); may administer lower infusion rates if patient exhibits marked sensitivity to insulin and resolution of acidosis can be achieved
• Transition to SC insulin regimen once ketoacidosis resolved; to ensure adequate plasma insulin levels, overlap discontinuation of IV insulin and administration of SC insulin; timing of SC insulin administration prior to IV infusion discontinuation depends on type of insulin used (1-2 hour for regular insulin and 15-30 minutes for rapid acting insulin)

Hyperkalemia (Off-label)

• 0.1 unit/kg with 400 mg/kg of glucose administered IV; (insulin to glucose ratio 1 unit of insulin for every 4 g of glucose recommended)

Dosing Considerations

• Dosage of human insulin, which is always expressed in USP units, must be based on the results of blood and urine glucose tests and must be carefully individualized to optimal effect
• Approximately 50-75% of the total daily insulin requirements are given as intermediate- or long-acting insulin administered in 1-2 injections
• Rapid- or short-acting insulin should be used before or at mealtimes to satisfy the remaining balance of the total daily insulin requirements
• Premixed combinations are available that deliver a rapid- or short-acting component at the same time as the intermediate- or long-acting component

• Overdose can cause hypoglycemia and hypokalemia. Mild hypoglycemia can be treated with oral glucose, and in addition, with adjustments in insulin dosage, meal patterns and exercises.
• Severe hypoglycemia can cause seizure, coma, or neurologic impairment and is treated with concentrated intravenous glucose or intramuscular/subcutaneous glucagon.
• Hypokalemia is treated with oral or intravenous potassium. 

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Severe Interactions of insulin include:
  • pramlintide
• Serious Interactions of insulin include:
  • Ethanol
  • macimorelin
• Insulin regular human has moderate interactions with at least 127 different drugs.
• Insulin regular human has mild interactions with at least 78 different drugs.

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information.

Check with your doctor or health care provider if you have any questions about the medication.

• Diabetic patients who wish to conceive should use adequate contraception until glycemic control is achieved.
• Good control of diabetes during pregnancy improves maternal and fetal outcomes.
• Insulin is the preferred treatment for type 1 and type 2 diabetes mellitus in pregnancy, as well as gestational diabetes mellitus, if treatment is required for diabetes control.
• Insulin requirements increase as pregnancy progresses and rapidly reduce after delivery. Glucose levels should be carefully monitored and insulin regimens appropriately adjusted in pregnant women.
• Regular insulin is used intravenously for glycemic control during labor.
• Insulin is present in breast milk but is degraded in the infant’s gastrointestinal tract and is not systemically absorbed. Good glucose control supports lactation and regular human insulin is considered safe for use by nursing mothers. Nursing mothers may require adjustments in insulin dose and/or diet.

• Never share your pen, needles, or syringes with others or use those used by others.
• Administer your insulin injection exactly as prescribed, any regimen change must be done only under your physician’s supervision.
• In case of overdose, seek medical help immediately.
• Rotate your injection sites and do not inject into areas of skin that have scars, pits, lumps, scales, or are tender or bruised.
• Always check labels before every injection to avoid errors of mix-up with other insulin products.
• Learn to monitor glucose levels and to recognize symptoms of hypoglycemia. Always carry sweets such as hard candy for immediate use and seek medical help if symptoms don’t resolve.
• Alcohol can have an additive effect and increase the risk for hypoglycemia, exercise caution.
• Hypoglycemia can impair concentration ability and reaction time, be cautious about activities such as driving and operating heavy machinery.