Novolin R U-100 Flexpen Inj 3ml
It is used to lower blood sugar in patients with high blood sugar (diabetes).
Drug Class
Antidiabetic agent
Pharmacologic Class
Insulin, short-acting
Pregnancy Category
Not available
FDA Approved
Oct 1982
DEA Schedule
Not Controlled
Overview
What is this medicine?
Insulin regular is a short-acting insulin that helps your body use sugar for energy. It starts working quickly, usually within 30 minutes, and is typically taken before meals to help control blood sugar spikes after eating.
How to Use This Medicine
Proper Use of This Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. This medication is administered via injection into the fatty tissue of the skin in the upper arm, thigh, buttocks, or stomach area. If you will be self-administering the injection, your doctor or nurse will instruct you on the proper technique.
Before use, wash your hands thoroughly. It is recommended to take this medication 30 minutes before meals. To minimize the risk of injection site reactions, rotate the injection site with each dose.
Important Administration Instructions
Do not shake the medication before use.
Avoid injecting into skin that is thickened, has pits or lumps, or is irritated, tender, bruised, red, scaly, hard, scarred, or has stretch marks.
Do not use the medication if the solution appears cloudy, is leaking, or contains particles. Additionally, do not use the medication if the solution has changed color.
Before injecting a dose, remove all pen needle covers (there may be two). If you are unsure about the type of pen needle you have or how to use it, consult your doctor.
After each injection, remove the needle and do not store the device with the needle attached.
Dispose of used needles in a designated needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow local regulations for proper disposal. If you have any questions, consult your doctor or pharmacist.
Special Considerations
Do not transfer this medication from the pen to a syringe or mix it with other types of insulin.
You may hear a clicking sound when preparing the dose. However, do not rely on the clicks to determine the dose, as this could result in an incorrect dose. Instead, follow the instructions provided by your doctor or pharmacist.
* Adhere to the diet and exercise plan recommended by your doctor. If you have any questions or concerns about what to do if you miss a meal or do not eat as much as usual, consult your doctor.
Storage and Disposal
Store unopened containers of this medication in the refrigerator. Do not freeze the medication, and do not use it if it has been frozen.
Missed Dose
If you forget to take a dose, consult your doctor for guidance on what to do. If you are unsure about what to do in the event of a missed dose, contact your doctor for advice.
To use this medication correctly, follow your doctor's instructions and read all the information provided. This medication is administered via injection into the fatty tissue of the skin in the upper arm, thigh, buttocks, or stomach area. If you will be self-administering the injection, your doctor or nurse will instruct you on the proper technique.
Before use, wash your hands thoroughly. It is recommended to take this medication 30 minutes before meals. To minimize the risk of injection site reactions, rotate the injection site with each dose.
Important Administration Instructions
Do not shake the medication before use.
Avoid injecting into skin that is thickened, has pits or lumps, or is irritated, tender, bruised, red, scaly, hard, scarred, or has stretch marks.
Do not use the medication if the solution appears cloudy, is leaking, or contains particles. Additionally, do not use the medication if the solution has changed color.
Before injecting a dose, remove all pen needle covers (there may be two). If you are unsure about the type of pen needle you have or how to use it, consult your doctor.
After each injection, remove the needle and do not store the device with the needle attached.
Dispose of used needles in a designated needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow local regulations for proper disposal. If you have any questions, consult your doctor or pharmacist.
Special Considerations
Do not transfer this medication from the pen to a syringe or mix it with other types of insulin.
You may hear a clicking sound when preparing the dose. However, do not rely on the clicks to determine the dose, as this could result in an incorrect dose. Instead, follow the instructions provided by your doctor or pharmacist.
* Adhere to the diet and exercise plan recommended by your doctor. If you have any questions or concerns about what to do if you miss a meal or do not eat as much as usual, consult your doctor.
Storage and Disposal
Store unopened containers of this medication in the refrigerator. Do not freeze the medication, and do not use it if it has been frozen.
Missed Dose
If you forget to take a dose, consult your doctor for guidance on what to do. If you are unsure about what to do in the event of a missed dose, contact your doctor for advice.
Lifestyle & Tips
- Always check your blood sugar levels as directed by your doctor.
- Follow a consistent meal plan and carbohydrate counting if advised.
- Engage in regular physical activity as recommended by your doctor.
- Learn proper injection technique and rotate injection sites to prevent skin problems.
- Never share your insulin pens or needles with others.
- Carry a source of fast-acting sugar (e.g., glucose tablets, juice) to treat low blood sugar.
- Inform all healthcare providers that you are taking insulin.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Individualized based on metabolic needs, blood glucose monitoring, and glycemic control goals. Typically administered 30 minutes before a meal.
Condition-Specific Dosing:
Type 1 Diabetes:
Initial total daily dose typically 0.5-1 unit/kg/day, divided into multiple injections (e.g., 1/3 as basal, 2/3 as bolus with meals, or split between regular and NPH). Regular insulin is usually 5-10 units per injection before meals, adjusted based on blood glucose.
Type 2 Diabetes:
Initial dose typically 0.1-0.2 units/kg/day or 4-6 units once or twice daily before meals, adjusted based on blood glucose.
Pediatric Dosing
Neonatal:
Not established (use cautiously, highly individualized, often in hospital settings)
Infant:
Highly individualized, typically 0.2-0.5 units/kg/day, adjusted based on blood glucose.
Child:
Highly individualized, typically 0.5-1 unit/kg/day, adjusted based on blood glucose.
Adolescent:
Highly individualized, typically 0.8-1.2 units/kg/day during puberty, adjusted based on blood glucose.
Dose Adjustments
Renal Impairment:
Mild:
May require dose reduction; monitor glucose closely.
Moderate:
Requires dose reduction; monitor glucose closely.
Severe:
Requires significant dose reduction; monitor glucose closely.
Dialysis:
Requires significant dose reduction; monitor glucose closely, especially post-dialysis.
Hepatic Impairment:
Mild:
May require dose reduction; monitor glucose closely.
Moderate:
Requires dose reduction; monitor glucose closely.
Severe:
Requires significant dose reduction; monitor glucose closely.
Pharmacology
Mechanism of Action
Insulin regular lowers blood glucose by stimulating peripheral glucose uptake, especially by skeletal muscle and fat, and by inhibiting hepatic glucose production. It inhibits lipolysis and proteolysis, and enhances protein synthesis.
Pharmacokinetics
Absorption:
Bioavailability:
Not applicable (administered subcutaneously)
Tmax:
1.5-3.5 hours (subcutaneous)
FoodEffect:
Administered 30 minutes before a meal to coincide with postprandial glucose rise.
Distribution:
Vd:
0.1-0.2 L/kg
ProteinBinding:
Minimal (<10%)
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 5-10 minutes (plasma half-life); functional half-life is longer due to absorption kinetics.
Clearance:
Not available
ExcretionRoute:
Renal (primarily)
Unchanged:
Not available
Pharmacodynamics
OnsetOfAction:
30 minutes
PeakEffect:
2-3 hours
DurationOfAction:
6-8 hours
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Some allergic reactions can be life-threatening, so prompt medical attention is crucial.
Signs of low potassium levels, including:
+ Muscle pain or weakness
+ Muscle cramps
+ An irregular heartbeat
Swelling in the arms or legs
Thick skin, pits, or lumps at the injection site
Low blood sugar, which may cause:
+ Dizziness or fainting
+ Blurred vision
+ Mood changes
+ Slurred speech
+ Headache
+ Feeling sleepy or weak
+ Shaking
+ Fast heartbeat
+ Confusion
+ Hunger
+ Sweating
+ Seizures
If you experience any of these symptoms, call your doctor right away. If you have low blood sugar, follow the instructions you have been given, which may include taking glucose tablets, liquid glucose, or some fruit juices.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or may only have mild ones. However, if you notice any of the following side effects or any other unusual symptoms, contact your doctor or seek medical attention:
Weight gain
Irritation at the injection site
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Some allergic reactions can be life-threatening, so prompt medical attention is crucial.
Signs of low potassium levels, including:
+ Muscle pain or weakness
+ Muscle cramps
+ An irregular heartbeat
Swelling in the arms or legs
Thick skin, pits, or lumps at the injection site
Low blood sugar, which may cause:
+ Dizziness or fainting
+ Blurred vision
+ Mood changes
+ Slurred speech
+ Headache
+ Feeling sleepy or weak
+ Shaking
+ Fast heartbeat
+ Confusion
+ Hunger
+ Sweating
+ Seizures
If you experience any of these symptoms, call your doctor right away. If you have low blood sugar, follow the instructions you have been given, which may include taking glucose tablets, liquid glucose, or some fruit juices.
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or may only have mild ones. However, if you notice any of the following side effects or any other unusual symptoms, contact your doctor or seek medical attention:
Weight gain
Irritation at the injection site
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Symptoms of severe hypoglycemia (e.g., confusion, seizures, unconsciousness)
- Symptoms of severe allergic reaction (e.g., rash over whole body, shortness of breath, wheezing, fast heartbeat, sweating)
- Signs of lipodystrophy (e.g., skin thickening or pitting at injection sites)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have low blood sugar (hypoglycemia).
This is not an exhaustive list of potential interactions. To ensure your safety, it is crucial to discuss all of the following with your doctor and pharmacist:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your existing health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm that it is safe to do so. This will help prevent potential interactions and ensure the safe use of this medication.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced.
If you have low blood sugar (hypoglycemia).
This is not an exhaustive list of potential interactions. To ensure your safety, it is crucial to discuss all of the following with your doctor and pharmacist:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your existing health problems
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to confirm that it is safe to do so. This will help prevent potential interactions and ensure the safe use of this medication.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Ensure you have the correct insulin product, as it comes in various containers such as vials, cartridges, and pens. Understand how to measure and prepare your dose accurately. If you have any questions or concerns, consult your doctor or pharmacist.
Be aware that this medication can cause low blood sugar, which may lead to seizures, loss of consciousness, permanent brain damage, and even death if not treated promptly. Discuss this risk with your doctor.
Additionally, this medication can cause low blood potassium levels, which may result in abnormal heart rhythms, severe breathing problems, and even death if left untreated. Consult your doctor if you experience any symptoms.
Until you understand how this medication affects you, avoid driving and other activities that require your full attention. Certain diabetes medications, such as pioglitazone or rosiglitazone, may increase the risk of heart failure when used with insulin. If you are taking one of these medications, discuss this risk with your doctor.
Stressful situations, such as fever, infection, injury, or surgery, can make it more challenging to control your blood sugar levels. Changes in physical activity, exercise, or diet can also impact your blood sugar levels.
Wear a medical alert identification to ensure prompt treatment in case of an emergency. Do not drive if you have recently experienced low blood sugar, as it can increase your risk of being involved in an accident.
Monitor your blood sugar levels as directed by your doctor. Regular blood tests will also be necessary to assess your condition. Consult your doctor to discuss any concerns or questions you may have.
Before consuming alcohol or using products containing alcohol, consult your doctor. Never share your insulin product, including pens, cartridge devices, needles, or syringes, with anyone else, even if the needle has been changed. Sharing can transmit infections, including those you may not be aware of having.
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects. Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding, as you will need to discuss the benefits and risks of this medication for both you and your baby.
Be aware that this medication can cause low blood sugar, which may lead to seizures, loss of consciousness, permanent brain damage, and even death if not treated promptly. Discuss this risk with your doctor.
Additionally, this medication can cause low blood potassium levels, which may result in abnormal heart rhythms, severe breathing problems, and even death if left untreated. Consult your doctor if you experience any symptoms.
Until you understand how this medication affects you, avoid driving and other activities that require your full attention. Certain diabetes medications, such as pioglitazone or rosiglitazone, may increase the risk of heart failure when used with insulin. If you are taking one of these medications, discuss this risk with your doctor.
Stressful situations, such as fever, infection, injury, or surgery, can make it more challenging to control your blood sugar levels. Changes in physical activity, exercise, or diet can also impact your blood sugar levels.
Wear a medical alert identification to ensure prompt treatment in case of an emergency. Do not drive if you have recently experienced low blood sugar, as it can increase your risk of being involved in an accident.
Monitor your blood sugar levels as directed by your doctor. Regular blood tests will also be necessary to assess your condition. Consult your doctor to discuss any concerns or questions you may have.
Before consuming alcohol or using products containing alcohol, consult your doctor. Never share your insulin product, including pens, cartridge devices, needles, or syringes, with anyone else, even if the needle has been changed. Sharing can transmit infections, including those you may not be aware of having.
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects. Inform your doctor if you are pregnant, plan to become pregnant, or are breastfeeding, as you will need to discuss the benefits and risks of this medication for both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe hypoglycemia (low blood sugar)
- Confusion
- Dizziness
- Sweating
- Tremor
- Blurred vision
- Seizures
- Loss of consciousness
What to Do:
Immediately consume fast-acting carbohydrates (e.g., glucose tablets, fruit juice, regular soda). If severe or unconscious, administer glucagon if available and call emergency medical services (e.g., 911 in the US). Call 1-800-222-1222 (Poison Control) for further guidance.
Drug Interactions
Major Interactions
- Beta-blockers (may mask hypoglycemia symptoms)
- Thiazolidinediones (TZDs) (increased risk of fluid retention and heart failure)
- Corticosteroids (may increase insulin requirements)
- Diuretics (thiazide and loop) (may increase insulin requirements)
- Sympathomimetics (e.g., albuterol, epinephrine) (may increase insulin requirements)
- Danazol (may increase insulin requirements)
- Growth hormone (may increase insulin requirements)
- Protease inhibitors (may increase insulin requirements)
- Atypical antipsychotics (may increase insulin requirements)
Moderate Interactions
- ACE inhibitors (may enhance glucose-lowering effect)
- Angiotensin receptor blockers (ARBs) (may enhance glucose-lowering effect)
- Salicylates (e.g., aspirin) (may enhance glucose-lowering effect)
- Sulfonamide antibiotics (may enhance glucose-lowering effect)
- Monoamine oxidase inhibitors (MAOIs) (may enhance glucose-lowering effect)
- Alcohol (may potentiate hypoglycemic effect)
- Octreotide/Lanreotide (may increase or decrease insulin requirements)
- Pentamidine (may cause hypoglycemia followed by hyperglycemia)
Monitoring
Baseline Monitoring
HbA1c
Rationale: To establish baseline glycemic control and set treatment goals.
Timing: Prior to initiation
Fasting Plasma Glucose (FPG)
Rationale: To establish baseline glucose levels.
Timing: Prior to initiation
Renal function (SCr, eGFR)
Rationale: To assess kidney function as insulin clearance is renal.
Timing: Prior to initiation
Hepatic function (ALT, AST)
Rationale: To assess liver function as insulin is metabolized in the liver.
Timing: Prior to initiation
Routine Monitoring
Self-monitoring of Blood Glucose (SMBG)
Frequency: Multiple times daily (pre-meal, post-meal, bedtime, and as needed for symptoms of hypoglycemia)
Target: Individualized, typically 80-130 mg/dL pre-meal, <180 mg/dL 1-2 hours post-meal
Action Threshold: Below 70 mg/dL (hypoglycemia), above target range (hyperglycemia)
HbA1c
Frequency: Every 3-6 months
Target: Individualized, typically <7%
Action Threshold: Above target range (consider dose adjustment or treatment intensification)
Weight
Frequency: Regularly (e.g., monthly or quarterly)
Target: Maintain healthy weight
Action Threshold: Significant unexplained weight gain or loss
Injection sites
Frequency: Daily with each injection
Target: No signs of lipodystrophy or irritation
Action Threshold: Presence of lumps, pits, or redness (rotate sites)
Symptom Monitoring
- Symptoms of hypoglycemia (e.g., sweating, tremor, dizziness, confusion, hunger, irritability, blurred vision, palpitations)
- Symptoms of hyperglycemia (e.g., increased thirst, frequent urination, fatigue, blurred vision)
- Signs of injection site reactions (e.g., redness, swelling, itching, pain, lipodystrophy)
Special Patient Groups
Pregnancy
Insulin is the preferred treatment for diabetes in pregnancy. Insulin regular is considered safe and effective for managing gestational diabetes and pre-existing diabetes during pregnancy. Close monitoring of blood glucose is essential.
Trimester-Specific Risks:
First Trimester:
No known teratogenic effects. Tight glycemic control is crucial to prevent congenital anomalies.
Second Trimester:
Insulin requirements may increase due to hormonal changes.
Third Trimester:
Insulin requirements typically continue to increase. Close monitoring for hypoglycemia is important.
Lactation
Insulin is compatible with breastfeeding. It is a large protein molecule and is not excreted into breast milk in clinically significant amounts. It is not expected to cause adverse effects in a breastfed infant.
Infant Risk:
L1 (Safest)
Pediatric Use
Insulin regular is safe and effective for use in pediatric patients with diabetes. Dosing must be highly individualized based on age, weight, pubertal status, and glycemic control. Close monitoring for hypoglycemia is critical.
Geriatric Use
No overall differences in safety or effectiveness have been observed between elderly and younger patients, but greater sensitivity to insulin's effects and increased risk of hypoglycemia may occur. Renal and hepatic function should be monitored, and dose adjustments may be necessary.
Clinical Information
Clinical Pearls
- Insulin regular is a short-acting insulin, typically administered 30 minutes before meals to cover the postprandial glucose rise.
- It can be mixed with NPH insulin (intermediate-acting) in the same syringe, but regular insulin should be drawn up first ('clear before cloudy').
- Always verify the insulin type (U-100, U-500) and concentration to prevent dosing errors.
- Patients should be educated on the signs and symptoms of hypoglycemia and how to treat it.
- Injection site rotation is crucial to prevent lipodystrophy and ensure consistent absorption.
- Stress, illness, and changes in diet or exercise can significantly impact insulin requirements.
Alternative Therapies
- Rapid-acting insulins (e.g., insulin aspart, insulin lispro, insulin glulisine)
- Intermediate-acting insulins (e.g., NPH insulin)
- Long-acting insulins (e.g., insulin glargine, insulin detemir, insulin degludec)
- Premixed insulins (e.g., Novolin 70/30, Humulin 70/30)
- Oral antidiabetic agents (e.g., metformin, sulfonylureas, SGLT2 inhibitors, GLP-1 receptor agonists, DPP-4 inhibitors) for Type 2 Diabetes.
Cost & Coverage
Average Cost:
Varies widely, typically $100-$300 per 3ml FlexPen
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (often preferred generic or formulary brand)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.