Insulatard InnoLet
Isophane insulin (NPH) – Intermediate-acting human insulin in a pre-filled pen
Quick Facts about Insulatard InnoLet
Key Takeaways About Insulatard InnoLet
- Intermediate-acting basal insulin: Insulatard InnoLet provides background insulin for up to 24 hours, with onset at approximately 1.5 hours and peak effect between 4 and 12 hours after injection
- Easy-to-use pre-filled pen: The InnoLet pen is specifically designed with a large dose dial and audible clicks for people who may have difficulty handling smaller devices, including those with visual impairment or limited dexterity
- Hypoglycemia is the main risk: Low blood sugar is the most common side effect; always carry glucose tablets or a sugary snack, and learn to recognise the warning signs
- Rotate injection sites: Inject subcutaneously in the thigh, abdominal wall, upper arm, or buttock, and rotate sites within the same region to reduce the risk of lipodystrophy
- Never inject intravenously: Insulatard InnoLet must only be injected under the skin (subcutaneously), never into a vein or muscle; doing so can cause severe hypoglycemia
What Is Insulatard InnoLet and What Is It Used For?
Insulatard InnoLet is a pre-filled disposable insulin pen that contains isophane (NPH) human insulin, an intermediate-acting insulin analogue used for the treatment of diabetes mellitus. It helps lower blood glucose levels in adults, adolescents, and children with type 1 or type 2 diabetes who need insulin therapy.
Insulatard InnoLet belongs to the class of intermediate-acting insulins, also known as NPH (Neutral Protamine Hagedorn) insulin. The active substance is human insulin produced using recombinant DNA technology in Saccharomyces cerevisiae (baker's yeast). This method ensures a highly pure insulin that is bioidentical to the insulin naturally produced by the human pancreas, minimising the risk of immune reactions.
The "InnoLet" designation refers to the specific delivery device: a large, ergonomic pre-filled pen designed by Novo Nordisk for patients who may have dexterity challenges, visual impairment, or arthritis. The pen features a large dose dial with audible clicks for each unit, making it easier to set the correct dose without strain. Each InnoLet pen contains 3 ml of insulin suspension at a concentration of 100 IU/ml, providing a total of 300 IU per pen.
In the management of type 1 diabetes, Insulatard InnoLet is typically used as part of a basal-bolus regimen. It serves as the basal (background) insulin, providing a steady level of insulin throughout the day and night, while a rapid-acting insulin such as insulin aspart (NovoRapid) is administered before meals to cover the spike in blood glucose after eating. In type 2 diabetes, Insulatard InnoLet may be used alone or in combination with oral antidiabetic agents (such as metformin or sulfonylureas) when these alone are insufficient to achieve glycaemic control.
According to the International Diabetes Federation (IDF), approximately 537 million adults worldwide live with diabetes as of 2021, a figure projected to rise to 783 million by 2045. Insulin remains an essential, life-saving medicine for all people with type 1 diabetes and many with type 2 diabetes. Isophane insulin has been on the WHO Model List of Essential Medicines since its inception, underscoring its critical role in global healthcare.
After subcutaneous injection, the isophane (NPH) insulin is absorbed gradually from the injection site into the bloodstream. It binds to insulin receptors on cells in the liver, muscle, and fat tissue, promoting the uptake of glucose from the blood into these cells. Simultaneously, it suppresses the liver's production of glucose. This dual mechanism effectively lowers blood sugar levels. The onset of action occurs within approximately 1.5 hours, the peak effect is reached between 4 and 12 hours, and the total duration of action extends up to 24 hours, depending on the dose, injection site, blood flow, temperature, and physical activity level.
What Should You Know Before Taking Insulatard InnoLet?
Before starting Insulatard InnoLet, inform your doctor about all medical conditions, allergies, and medications you are taking. Certain conditions and drug interactions can affect how insulin works and may require dose adjustments or extra monitoring.
Contraindications
You should not use Insulatard InnoLet if you:
- Are allergic to human insulin, isophane insulin, or any of the other ingredients in the product (including protamine sulphate, zinc chloride, glycerol, metacresol, phenol, disodium phosphate dihydrate, sodium hydroxide, hydrochloric acid, or water for injection)
- Are experiencing hypoglycemia (low blood sugar) – never inject insulin when your blood sugar is already too low
- Intend to inject it intravenously – Insulatard InnoLet must only be given subcutaneously (under the skin), never into a vein
- Plan to use it in an insulin infusion pump – isophane insulin is not suitable for continuous subcutaneous insulin infusion systems
Warnings and Precautions
Talk to your doctor, pharmacist, or diabetes nurse before using Insulatard InnoLet if any of the following apply to you:
- Kidney or liver disease: Impaired kidney or liver function may reduce the body's ability to break down insulin, which can lower your insulin requirements. More frequent blood glucose monitoring is essential.
- Adrenal, pituitary, or thyroid disorders: These conditions can affect blood sugar regulation and may require insulin dose adjustments.
- Intense physical exercise: Exercise increases glucose uptake by muscles, which can lead to hypoglycemia. You may need to reduce your insulin dose or eat more carbohydrates before and during physical activity.
- Illness or infection: Being sick (especially with fever, vomiting, or diarrhoea) can dramatically affect your insulin needs. During illness, monitor blood glucose more frequently and follow your sick-day management plan.
- Travelling across time zones: Changes in time zones may affect your injection schedule. Consult your doctor before travelling to plan your insulin timing.
- Switching from animal insulin: If you are switching from animal-source insulin to human insulin, your dose may need to be changed. The switch should always be done under medical supervision.
- Hypoglycemia unawareness: If you have had diabetes for a long time or have had frequent episodes of low blood sugar, you may lose the warning signs of hypoglycemia. Speak to your doctor about adjusting your treatment targets.
Severe hypoglycemia can cause loss of consciousness, seizures, and even death if untreated. Always carry fast-acting glucose (such as glucose tablets, juice, or sugary sweets). Inform people around you that you have diabetes so they can help in an emergency. If you lose consciousness due to low blood sugar, someone should administer glucagon (if available) and call emergency services immediately.
Pregnancy and Breastfeeding
If you are pregnant, planning to become pregnant, or breastfeeding, consult your doctor before using Insulatard InnoLet. Insulin does not cross the placenta and is not known to be harmful during pregnancy. In fact, good glycaemic control during pregnancy is critically important for the health of both mother and baby. However, insulin requirements often change substantially during pregnancy – typically decreasing in the first trimester and increasing during the second and third trimesters. After delivery, insulin needs usually return quickly to pre-pregnancy levels.
Breastfeeding mothers can use Insulatard InnoLet safely. Insulin is broken down in the infant's gastrointestinal tract and does not affect the baby. However, your caloric requirements and insulin dose may need adjustment during breastfeeding. Your doctor can help you manage your diabetes during this period.
How Does Insulatard InnoLet Interact with Other Drugs?
Several medications can increase or decrease the blood-sugar-lowering effect of Insulatard InnoLet. Always inform your doctor about all medicines, supplements, and herbal products you are taking to avoid dangerous interactions.
Drug interactions with insulin are clinically significant because they can unpredictably alter blood glucose levels, leading to either hypoglycemia (dangerously low blood sugar) or hyperglycemia (high blood sugar). The following table summarises the most important drug interactions with Insulatard InnoLet. Your healthcare provider should adjust your insulin dose when any of these medications are started, stopped, or changed.
Drugs That Increase Insulin Effect (Risk of Hypoglycemia)
| Drug / Drug Class | Mechanism | Clinical Advice |
|---|---|---|
| Oral antidiabetic agents (metformin, sulfonylureas, GLP-1 agonists) | Additive glucose-lowering effect | Monitor blood glucose closely when combined; dose reduction of insulin may be needed |
| ACE inhibitors (enalapril, ramipril, lisinopril) | May increase insulin sensitivity | More frequent glucose monitoring recommended; insulin dose may need to be lowered |
| MAO inhibitors | Enhance insulin secretion and sensitivity | Significant hypoglycemia risk; close monitoring essential |
| Salicylates (high-dose aspirin) | Reduce hepatic glucose production | Relevant only at anti-inflammatory doses; low-dose aspirin generally safe |
| Non-selective beta-blockers (propranolol) | May mask hypoglycemia symptoms and prolong recovery | Cardio-selective beta-blockers (metoprolol, bisoprolol) preferred in diabetes |
| Alcohol | Inhibits hepatic gluconeogenesis | Avoid heavy alcohol intake; always eat food with alcohol; delayed hypoglycemia can occur hours later |
Drugs That Decrease Insulin Effect (Risk of Hyperglycemia)
| Drug / Drug Class | Mechanism | Clinical Advice |
|---|---|---|
| Corticosteroids (prednisolone, dexamethasone) | Increase hepatic glucose production and reduce insulin sensitivity | Insulin dose often needs substantial increase; monitor glucose frequently |
| Thiazide diuretics (hydrochlorothiazide) | Impair insulin secretion and reduce insulin sensitivity | Monitor glucose when starting or stopping; dose adjustment may be needed |
| Thyroid hormones (levothyroxine) | Increase glucose absorption and hepatic glucose output | Reassess insulin needs when thyroid function changes |
| Oral contraceptives | May decrease insulin sensitivity | Monitor blood glucose; small dose adjustments may be required |
| Sympathomimetics (salbutamol, terbutaline) | Stimulate glycogenolysis and gluconeogenesis | Monitor glucose during use, especially with systemic (not inhaled) administration |
| Growth hormone (somatotropin) | Reduces insulin sensitivity | May require significant insulin dose increase |
What Is the Correct Dosage of Insulatard InnoLet?
The dose of Insulatard InnoLet is always individualised by your healthcare provider based on your blood glucose levels, type of diabetes, diet, physical activity, and other individual factors. There is no single standard dose – your doctor will determine the right amount for you.
Insulin dosing is one of the most personalised aspects of diabetes management. Your doctor will set your initial dose based on your body weight, blood glucose patterns, type of diabetes, and lifestyle. Over time, the dose is fine-tuned based on your blood glucose monitoring results, HbA1c levels, and any changes in your health or routine. The following provides general guidance, but your prescribed dose takes precedence.
Adults
Type 1 Diabetes
Total daily insulin requirement is typically 0.5–1.0 IU/kg/day. Of this, approximately 40–60% is often given as basal insulin (Insulatard InnoLet), with the remainder as rapid-acting insulin before meals. Insulatard InnoLet is usually injected once or twice daily – commonly at bedtime for once-daily dosing, or in the morning and at bedtime for twice-daily dosing.
Type 2 Diabetes
When oral medications alone are insufficient, Insulatard InnoLet may be added to the regimen. A common starting dose is 10 IU at bedtime (or 0.1–0.2 IU/kg/day), which is then titrated upward by 2–4 IU every 3–7 days based on fasting blood glucose targets. Some patients may eventually require higher doses, particularly those with significant insulin resistance.
Children and Adolescents
Paediatric Dosing
Insulatard InnoLet can be used in children of all ages. In prepubertal children, the total daily insulin requirement is usually 0.7–1.0 IU/kg/day. During puberty, insulin requirements often increase significantly to 1.0–2.0 IU/kg/day due to hormonal changes that reduce insulin sensitivity. The InnoLet device is particularly suitable for adolescents learning self-injection due to its simple design. Dosing should always be guided by a paediatric endocrinologist or diabetes specialist.
Elderly Patients
Older Adults (65+ years)
There is no specific age-related dose adjustment. However, elderly patients may be more susceptible to hypoglycemia due to reduced counter-regulatory hormone responses, impaired kidney function, polypharmacy, and irregular eating patterns. The American Diabetes Association (ADA) recommends less stringent glycaemic targets (HbA1c < 8.0% rather than < 7.0%) for older adults with limited life expectancy or multiple comorbidities to reduce hypoglycemia risk. Blood glucose monitoring should be intensified, and doses adjusted conservatively.
Missed Dose
If you forget a dose of Insulatard InnoLet, check your blood glucose level as soon as you remember. If your blood sugar is high, take your insulin as soon as possible and adjust subsequent doses as advised by your doctor. Do not take a double dose to compensate for the missed injection. If you are unsure how to handle a missed dose, contact your healthcare provider or diabetes nurse for personalised advice. Missing doses regularly can lead to poor blood sugar control and increase the risk of long-term diabetes complications.
Overdose
An insulin overdose causes hypoglycemia. Mild hypoglycemia (sweating, trembling, hunger) can be treated by eating 15–20 grams of fast-acting carbohydrates (glucose tablets, juice, or sugar). Wait 15 minutes, check your blood sugar, and repeat if necessary. Severe hypoglycemia (confusion, loss of consciousness, seizures) is a medical emergency – someone should administer glucagon injection if available and call emergency services immediately. Do not attempt to give food or drink to an unconscious person. After recovering from severe hypoglycemia, seek medical attention.
How Should You Inject Insulatard InnoLet?
Insulatard InnoLet is injected subcutaneously (under the skin) using the pre-filled pen. Always resuspend the insulin by rolling and tipping the pen before each injection, and rotate your injection sites to prevent skin changes.
Correct injection technique is essential for reliable insulin absorption and blood glucose control. The InnoLet pen is designed for ease of use, but it is important to follow the steps carefully:
- Prepare the pen: Remove the pen cap and check that the insulin remaining in the cartridge is sufficient for your dose. Look at the insulin – before mixing, it should be white and cloudy with a white sediment at the bottom.
- Resuspend the insulin: Roll the pen between your palms at least 10 times, then tip the pen up and down at least 10 times until the suspension is uniformly white and cloudy. If the insulin does not look uniform or has lumps, do not use it.
- Attach a new needle: Use a new NovoFine or NovoTwist needle for each injection. Remove the outer and inner needle caps.
- Perform an air shot: Dial 2 units. Hold the pen with the needle pointing up, tap gently to move air bubbles to the top, and press the push-button. A drop of insulin should appear at the needle tip. Repeat if needed.
- Set your dose: Turn the dose selector to your prescribed number of units. The InnoLet pen can deliver 1–50 units in increments of 1 unit.
- Choose and clean the injection site: Recommended sites are the thigh, abdominal wall (avoiding the area directly around the navel), upper arm, or buttock. Rotate within the chosen region. The thigh is recommended for self-injection.
- Inject: Insert the needle into the skin. Press the push-button fully in and hold it down. Count slowly to at least 6 before withdrawing the needle to ensure the full dose is delivered.
- Remove and dispose: Remove the needle, replace the outer cap, unscrew, and dispose safely in a sharps container.
Insulin absorption speed varies by injection site. The abdominal wall provides the fastest and most consistent absorption, followed by the upper arm, thigh, and buttock (slowest). For NPH insulin, the thigh is commonly recommended for bedtime injections as the slower absorption provides a more sustained overnight effect. Always inject into the same body region at the same time of day, but rotate the exact spot within that region to prevent lipodystrophy.
What Are the Side Effects of Insulatard InnoLet?
Like all medicines, Insulatard InnoLet can cause side effects, although not everybody gets them. The most common side effect is hypoglycemia (low blood sugar). Most other side effects are uncommon or rare and typically resolve with continued treatment.
Side effects of insulin therapy are generally well characterised and manageable. The frequency categories below follow the international convention used by the European Medicines Agency (EMA) and are based on data from clinical trials and post-marketing surveillance.
Very Common
- Hypoglycemia (low blood sugar): Symptoms include sweating, trembling, hunger, palpitations, blurred vision, difficulty concentrating, drowsiness, headache, anxiety, and irritability. Severe hypoglycemia can cause confusion, seizures, or loss of consciousness.
Common
- Injection site reactions: Redness, swelling, itching, warmth, or pain at the injection site. These usually resolve within a few days to weeks.
- Lipodystrophy: Lumps (lipohypertrophy) or dents (lipoatrophy) in the skin at frequently used injection sites. Prevented by rotating injection sites.
Uncommon
- Visual disturbances: Blurred vision or temporary changes in refraction, especially when starting insulin therapy. Usually resolves within a few weeks as blood glucose stabilises.
- Oedema: Fluid retention (swelling in ankles or feet), particularly at the start of treatment. Usually transient.
- Peripheral neuropathy: Rarely, rapid improvement in blood glucose control can cause temporary painful neuropathy (acute painful neuropathy of rapid glycaemic control).
Rare
- Allergic reactions: Generalised skin rash, itching, urticaria (hives), or very rarely anaphylaxis. Seek immediate medical attention for breathing difficulties, rapid heartbeat, or facial swelling.
- Insulin antibodies: The body may develop antibodies against insulin, which can occasionally affect dose requirements.
Contact your doctor or go to the nearest emergency department immediately if you experience: signs of severe allergic reaction (difficulty breathing, swelling of face/lips/tongue, widespread rash); signs of severe hypoglycemia (loss of consciousness, convulsions); or diabetic ketoacidosis (nausea, vomiting, abdominal pain, excessive thirst, fruity breath odour, rapid breathing).
How Should You Store Insulatard InnoLet?
Store unused Insulatard InnoLet pens in the refrigerator at 2–8°C. Once in use, keep the pen at room temperature (below 30°C) for up to 6 weeks. Never freeze insulin and protect it from direct heat and sunlight.
Proper storage of insulin is essential to maintain its effectiveness. Insulin that has been exposed to extreme temperatures, direct sunlight, or freezing loses its potency and should be discarded. The following guidelines apply to Insulatard InnoLet:
- Before first use: Store in the refrigerator at 2–8°C (36–46°F). Keep away from the freezer compartment. Do not freeze.
- After first use (in-use): Keep at room temperature (below 30°C / 86°F) for up to 6 weeks. Do not return to the refrigerator once opened. Refrigerating in-use pens can cause temperature fluctuations that may affect the insulin.
- Protect from light: Keep the pen cap on when not in use to protect the insulin from light.
- Do not freeze: Frozen insulin is permanently damaged and must be discarded, even if thawed. Check pens stored in luggage during air travel.
- Check before each use: After resuspending, the insulin should appear uniformly white and cloudy. Do not use if it appears clear, coloured, or if particles are visible.
- Expiry date: Do not use after the expiry date printed on the label and outer packaging.
- Disposal: Do not throw the pen or needles in household waste. Use a sharps container and follow your local guidelines for disposal of medical waste.
When travelling, carry your insulin in your hand luggage (aircraft hold temperatures can freeze insulin). Use an insulated travel case in hot climates. Carry a letter from your doctor explaining your need for insulin supplies and injection equipment, especially for international air travel. Keep a spare pen available in case of loss or damage.
What Does Insulatard InnoLet Contain?
Each millilitre of Insulatard InnoLet suspension contains 100 IU of isophane (NPH) human insulin (produced by recombinant DNA technology in Saccharomyces cerevisiae) along with several excipients that stabilise the formulation.
Understanding the composition of your insulin is important, particularly if you have known allergies to any pharmaceutical excipients. Insulatard InnoLet contains the following ingredients:
Active substance:
- Insulin human (isophane/NPH) – 100 IU/ml (equivalent to approximately 3.5 mg/ml)
Excipients (inactive ingredients):
- Protamine sulphate – binds to insulin to create the isophane complex, providing intermediate duration of action
- Zinc chloride – stabilises the insulin hexamer structure
- Glycerol – tonicity agent to make the solution isotonic with body fluids
- Metacresol – preservative
- Phenol – preservative
- Disodium phosphate dihydrate – buffer to maintain pH
- Sodium hydroxide / hydrochloric acid – pH adjustment
- Water for injections – solvent
People with a known allergy to protamine should exercise caution, as protamine sulphate is an essential component of all NPH (isophane) insulin preparations. Protamine allergy is rare but has been reported, particularly in individuals who have had prior exposure to protamine (for example, as a heparin reversal agent during surgery). If you suspect a protamine allergy, discuss alternative insulin formulations (such as long-acting insulin analogues like insulin glargine or insulin detemir) with your endocrinologist.
Insulatard InnoLet is available as a pack of 5 pre-filled disposable pens, each containing 3 ml of insulin suspension (300 IU per pen). The pen is made of polypropylene plastic and is designed for single-patient use only. Do not share your pen with another person, even if the needle is changed, as this carries a risk of cross-contamination and infection transmission.
Frequently Asked Questions About Insulatard InnoLet
Insulatard InnoLet is an intermediate-acting insulin (isophane/NPH insulin) used to treat diabetes mellitus in adults, adolescents, and children. It is prescribed for both type 1 diabetes (where the pancreas produces no insulin) and type 2 diabetes (where the body cannot produce enough insulin or use it effectively). It provides background insulin coverage for up to 24 hours and is typically injected once or twice daily, often combined with a rapid-acting insulin before meals for comprehensive blood glucose control.
First, roll the pen between your palms 10 times and tip it up and down 10 times until the insulin looks uniformly white and cloudy. Attach a new needle, perform an air shot of 2 units, then dial your prescribed dose. Clean the injection site and insert the needle subcutaneously (into the fatty tissue under the skin). Press the push-button fully in, count to at least 6, then remove the needle. Always use a new needle for each injection and dispose of needles in a sharps container.
Insulatard InnoLet is an intermediate-acting insulin with onset at about 1.5 hours, peak effect at 4–12 hours, and duration up to 24 hours. It provides steady background (basal) insulin. Rapid-acting insulins (like NovoRapid/insulin aspart) start working within 10–20 minutes, peak at 1–3 hours, and last 3–5 hours. They are taken just before meals to handle the rise in blood sugar after eating. Many people with type 1 diabetes use both types together in a basal-bolus regimen.
Your ability to drive may be impaired if you experience hypoglycemia (low blood sugar), as it can affect concentration and reaction time. Always check your blood glucose before driving. Do not drive if your blood sugar is below your target range. Carry glucose tablets and a blood glucose meter in your vehicle. If you feel symptoms of hypoglycemia while driving, pull over safely, turn off the engine, treat the low blood sugar, and wait until you have fully recovered before continuing. Local driving regulations for people with diabetes vary by country – check with your licensing authority.
An insulin overdose causes hypoglycemia (low blood sugar). For mild symptoms (sweating, trembling, hunger), immediately eat or drink 15–20 grams of fast-acting carbohydrates such as glucose tablets, fruit juice, or a sugary drink. Wait 15 minutes, recheck your blood glucose, and repeat if still low. Follow up with a longer-acting carbohydrate snack (e.g., a sandwich or crackers). For severe hypoglycemia (confusion, loss of consciousness, seizures), someone should administer a glucagon injection if available and call emergency services immediately. Always inform your doctor about any overdose episode.
Before first use, store in the refrigerator at 2–8°C (36–46°F). Do not freeze. Once in use, the pen can be kept at room temperature (below 30°C / 86°F) for up to 6 weeks. Do not refrigerate the in-use pen. Protect from direct sunlight and heat. Always check that the insulin appears uniformly white and cloudy after gentle mixing before each injection – do not use if it looks clear, discoloured, or contains particles.
References
- European Medicines Agency (EMA). Insulatard – Summary of Product Characteristics. Available at: www.ema.europa.eu. Accessed February 2026.
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List (2023). Geneva: WHO; 2023.
- American Diabetes Association (ADA). Standards of Care in Diabetes – 2025. Diabetes Care. 2025;48(Supplement 1).
- International Diabetes Federation (IDF). IDF Diabetes Atlas, 10th edition. Brussels: IDF; 2021. Available at: diabetesatlas.org.
- National Institute for Health and Care Excellence (NICE). Type 1 diabetes in adults: diagnosis and management [NG17]. Updated 2022.
- National Institute for Health and Care Excellence (NICE). Type 2 diabetes in adults: management [NG28]. Updated 2022.
- Holt RIG, DeVries JH, Hess-Fischl A, et al. The management of type 1 diabetes in adults. A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD). Diabetes Care. 2021;44(11):2589–2625.
- Novo Nordisk. Insulatard InnoLet – Patient Information Leaflet. Bagsværd, Denmark: Novo Nordisk A/S.
- British National Formulary (BNF). Insulin (human) – Isophane. Available at: bnf.nice.org.uk. Accessed February 2026.
- Swinnen SG, Simon AC, Holleman F, Hoekstra JB, DeVries JH. Insulin detemir versus insulin glargine for type 2 diabetes mellitus. Cochrane Database of Systematic Reviews. 2011;(7):CD006383.
About the Medical Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, comprising licensed physicians specialising in endocrinology, diabetes, and internal medicine. Our editorial process follows international guidelines from the WHO, ADA, IDF, and NICE.
Level 1A – Based on systematic reviews and meta-analyses of randomised controlled trials. All medical claims are fact-checked against peer-reviewed sources.
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