Insuman Rapid (Insulin Human)
Fast-acting soluble human insulin for diabetes management
Quick Facts About Insuman Rapid
Key Takeaways About Insuman Rapid
- Fast-acting human insulin: Insuman Rapid begins working within 30 minutes and peaks at 1-3 hours, making it suitable for mealtime blood sugar control
- Identical to natural insulin: Contains regular human insulin produced by recombinant DNA technology, structurally identical to the insulin made by the human pancreas
- Hypoglycaemia is the main risk: Low blood sugar is the most common adverse effect; always carry glucose tablets or a sugary drink
- Inject before meals: Ideally administered 15-20 minutes before eating for optimal blood glucose control
- Store correctly: Unopened vials in the refrigerator (2-8 °C); once opened, keep at room temperature (below 25 °C) for up to 4 weeks
What Is Insuman Rapid and What Is It Used For?
Insuman Rapid is a fast-acting injectable insulin containing human insulin produced by recombinant DNA technology using Escherichia coli (E. coli). It is prescribed for the treatment of diabetes mellitus in adults, adolescents, and children who require exogenous insulin to maintain healthy blood glucose levels.
Insuman Rapid belongs to the pharmacological class of fast-acting insulins (ATC code: A10AB01). The active substance is soluble insulin human, which is structurally identical to the insulin produced by the beta cells of the human pancreas. Unlike insulin analogues such as insulin lispro (Humalog) or insulin aspart (NovoRapid), Insuman Rapid is unmodified human insulin, meaning its amino acid sequence is exactly the same as endogenous insulin.
The primary therapeutic indication for Insuman Rapid is the management of diabetes mellitus. This includes type 1 diabetes mellitus, where the pancreas produces little or no insulin, and type 2 diabetes mellitus, when oral antidiabetic agents and lifestyle modifications alone are insufficient to achieve adequate glycaemic control. Insuman Rapid is also used in gestational diabetes when insulin therapy is required, and in hospital settings for the management of diabetic emergencies such as diabetic ketoacidosis (DKA) and hyperglycaemic hyperosmolar state (HHS).
When injected subcutaneously, Insuman Rapid has a rapid onset of action, typically beginning to lower blood glucose within 30 minutes. The maximum glucose-lowering effect occurs between 1 and 3 hours after injection, and the total duration of action is approximately 5 to 7 hours. This pharmacokinetic profile makes it well-suited for controlling postprandial (after-meal) blood glucose spikes. It should be injected 15 to 20 minutes before a meal for optimal timing of its blood-glucose-lowering action.
Insuman Rapid can also be administered intravenously under medical supervision, which is unique among insulin preparations as not all can be given by this route. Intravenous insulin has an immediate onset of action and is used in critical care settings for rapid blood glucose management.
Insuman Rapid is regular human insulin, not a rapid-acting insulin analogue. Rapid-acting analogues (insulin lispro, aspart, glulisine) work faster (onset 10-15 minutes) and have a shorter duration. Your doctor will choose the most appropriate insulin for your individual needs. Do not switch insulin types without medical advice.
What Should You Know Before Taking Insuman Rapid?
Before starting Insuman Rapid, inform your doctor about all medical conditions, allergies, and other medications you take. Never use Insuman Rapid if you are allergic to insulin or any of the excipients, or to treat low blood sugar (hypoglycaemia).
Contraindications
You must not use Insuman Rapid in the following situations:
- Hypersensitivity: If you are allergic to insulin human or to any of the other ingredients in Insuman Rapid, including metacresol (a preservative), protamine sulphate, sodium dihydrogen phosphate, glycerol, sodium hydroxide, or hydrochloric acid
- Hypoglycaemia: Never use Insuman Rapid when your blood glucose is already low or dropping; insulin will further reduce blood glucose and can cause life-threatening hypoglycaemia
- Insulin infusion pumps: Insuman Rapid 40 IU/ml must not be used in insulin infusion pumps (the 100 IU/ml formulation may be used in certain compatible pumps under medical supervision)
Warnings and Precautions
Several important precautions should be considered before and during treatment with Insuman Rapid. Discuss these with your healthcare provider:
- Hypoglycaemia awareness: Repeated episodes of hypoglycaemia may reduce your ability to recognise the early warning signs (hypoglycaemia unawareness). This is particularly dangerous and more common in elderly patients, those on beta-blocker therapy, and those with long-standing diabetes. Blood glucose monitoring is essential
- Renal and hepatic impairment: Insulin requirements may be reduced in patients with kidney or liver disease because insulin clearance is decreased. Close monitoring of blood glucose is required, and dose adjustments may be necessary
- Illness and stress: Infections, fever, surgery, emotional stress, and other illnesses can significantly increase insulin requirements. Monitor blood glucose more frequently during illness and adjust doses in consultation with your healthcare team
- Exercise: Physical activity increases glucose uptake by muscles and may reduce insulin requirements. Risk of hypoglycaemia increases during and after exercise. Adjust carbohydrate intake or insulin dose accordingly
- Injection site reactions: Rotate injection sites to prevent lipodystrophy (thickening or pitting of subcutaneous fat), which can alter insulin absorption. Common injection sites include the abdomen, thigh, upper arm, and buttock
- Driving and operating machinery: Hypoglycaemia impairs concentration and reaction time. Check blood glucose before driving and carry glucose tablets in the vehicle
- Alcohol: Alcohol can intensify and prolong the hypoglycaemic effect of insulin. Drink alcohol only in moderation and always with food
- Switching insulins: Any change in insulin type, brand, or concentration should only be made under medical supervision. A change may require dose adjustments
Pregnancy and Breastfeeding
If you are pregnant, planning to become pregnant, or breastfeeding, consult your doctor before using Insuman Rapid. Insulin requirements typically change during pregnancy: they tend to decrease during the first trimester and increase during the second and third trimesters. After delivery, insulin requirements usually fall rapidly to pre-pregnancy levels.
Insuman Rapid can be used during pregnancy. Human insulin does not cross the placenta in significant amounts, and there is extensive clinical experience supporting its safety. Good glycaemic control is essential throughout pregnancy to minimise risks to both the mother and the developing baby, including congenital malformations, macrosomia, and neonatal hypoglycaemia.
Breastfeeding mothers may use Insuman Rapid. Insulin is a natural protein that is degraded in the infant's gastrointestinal tract and is not absorbed. There are no restrictions on breastfeeding. However, adjustments to the insulin dose and diet may be necessary during the breastfeeding period, as caloric requirements increase.
How Does Insuman Rapid Interact with Other Drugs?
Insuman Rapid interacts with many commonly prescribed medications. Some drugs increase the risk of hypoglycaemia by enhancing insulin's glucose-lowering effect, while others may raise blood glucose levels and reduce insulin effectiveness. Always inform your healthcare provider of all medications you are taking.
Drug interactions with insulin are clinically significant because they can unpredictably alter blood glucose levels, leading to either hypoglycaemia or hyperglycaemia. The following tables summarise the most important interactions. Blood glucose should be monitored more frequently whenever a new medication is started, the dose of an existing medication is changed, or a medication is discontinued.
Drugs That May Increase Hypoglycaemia Risk
These medications can enhance the blood-glucose-lowering effect of Insuman Rapid, potentially leading to hypoglycaemia. Dose reduction of insulin may be necessary when these drugs are co-administered:
| Drug / Drug Class | Mechanism | Clinical Significance |
|---|---|---|
| Oral antidiabetic agents (metformin, sulfonylureas, SGLT2 inhibitors) | Additive glucose-lowering effect | High – dose adjustment often required |
| ACE inhibitors (enalapril, ramipril, lisinopril) | Increase insulin sensitivity | Moderate – monitor blood glucose |
| MAO inhibitors | Enhance insulin secretion and sensitivity | High – close monitoring essential |
| Salicylates (aspirin, high doses) | Increase peripheral glucose utilisation | Moderate – relevant at analgesic doses |
| Beta-blockers (propranolol, atenolol) | Mask hypoglycaemia symptoms; may prolong hypoglycaemia | High – may mask warning signs of low blood sugar |
| Fibrates (fenofibrate, gemfibrozil) | Improve insulin sensitivity | Low to moderate |
| Fluoxetine | Enhances insulin action | Moderate – monitor when initiating |
Drugs That May Decrease Insulin Effectiveness
These medications can raise blood glucose levels, counteracting the effect of Insuman Rapid. An increase in insulin dose may be required:
| Drug / Drug Class | Mechanism | Clinical Significance |
|---|---|---|
| Corticosteroids (prednisolone, dexamethasone) | Increase hepatic glucose production and insulin resistance | High – significant hyperglycaemia common |
| Thiazide diuretics (hydrochlorothiazide, bendroflumethiazide) | Reduce insulin secretion; increase insulin resistance | Moderate – dose adjustment may be needed |
| Thyroid hormones (levothyroxine) | Increase hepatic gluconeogenesis | Moderate – monitor when dose changes |
| Sympathomimetics (salbutamol, terbutaline) | Stimulate glycogenolysis and gluconeogenesis | Moderate – especially at high doses |
| Somatotropin (growth hormone) | Reduces insulin sensitivity | High – insulin requirements may increase substantially |
| Danazol | Induces insulin resistance | High – significant hyperglycaemia |
| Atypical antipsychotics (olanzapine, clozapine) | Impair glucose tolerance; increase insulin resistance | High – metabolic monitoring required |
Alcohol can both increase and decrease blood glucose levels. In the short term, alcohol inhibits hepatic gluconeogenesis and can cause delayed hypoglycaemia, sometimes hours after drinking. This effect is enhanced when combined with insulin. Moderate alcohol consumption with food is generally considered safe, but binge drinking or drinking on an empty stomach significantly increases the risk of severe hypoglycaemia.
What Is the Correct Dosage of Insuman Rapid?
The dose of Insuman Rapid is individualised for each patient based on blood glucose levels, type of diabetes, body weight, diet, physical activity, and other factors. There is no standard fixed dose. Your doctor will determine and regularly adjust your dose to achieve optimal blood glucose control.
Insulin dosing is highly individualised and there is no universal dose that applies to all patients. The target blood glucose levels and HbA1c, the insulin regimen, and the dose are determined by your healthcare provider based on a comprehensive assessment of your metabolic needs. Insuman Rapid is typically used as part of a basal-bolus regimen, where it provides the mealtime (bolus) component alongside a longer-acting basal insulin (such as Insuman Basal, insulin glargine, or insulin detemir).
Adults
Adult Dosing Guidelines
Total daily insulin requirement: Typically 0.5 to 1.0 IU per kilogram body weight per day, though this varies widely between individuals. Approximately 40-60% of the total daily dose is usually given as mealtime (bolus) insulin, with the remainder as basal insulin.
Administration: Insuman Rapid should be injected subcutaneously 15-20 minutes before a meal. The dose for each meal depends on the expected carbohydrate intake, pre-meal blood glucose level, and anticipated physical activity. Many patients use carbohydrate counting to calculate their mealtime insulin dose.
Insulin-to-carbohydrate ratio: A typical starting ratio is 1 IU per 10-15 grams of carbohydrate, but this varies considerably and must be individually determined.
Correction factor: Your doctor may also prescribe a correction dose (supplemental insulin) for pre-meal blood glucose above target. A typical correction factor is a reduction of 2-3 mmol/L (36-54 mg/dL) per 1 IU of insulin, but this must be individualised.
Children and Adolescents
Paediatric Dosing Guidelines
Total daily insulin requirement: In children, the total daily insulin dose is typically 0.5 to 1.5 IU per kilogram body weight per day. During puberty, insulin requirements often increase significantly and may exceed 1.5 IU/kg/day due to hormonal changes that increase insulin resistance.
Pre-pubertal children: Usually require 0.5-0.7 IU/kg/day. The mealtime and basal split follows similar principles to adult dosing but requires careful adjustment.
Adolescents: May require 1.0-1.5 IU/kg/day or more during puberty. Close monitoring and frequent dose adjustments are essential during this period of rapid growth and hormonal change.
Safety note: Children are particularly vulnerable to hypoglycaemia. Parents and caregivers should be trained to recognise the signs and symptoms of hypoglycaemia and to administer appropriate treatment, including glucagon injection for severe episodes.
Elderly Patients
Elderly Dosing Considerations
In elderly patients (over 65 years), insulin therapy should be initiated and dose increases should be made cautiously. Elderly patients are more susceptible to hypoglycaemia and may have reduced awareness of hypoglycaemic symptoms. Renal function should be monitored regularly, as declining kidney function reduces insulin clearance and may necessitate dose reductions. Less stringent HbA1c targets (e.g., below 8.0% or 64 mmol/mol) may be appropriate for older patients with significant comorbidities, limited life expectancy, or high risk of hypoglycaemia, as recommended by the American Diabetes Association (ADA).
Missed Dose
If you forget to inject Insuman Rapid before a meal, check your blood glucose level as soon as you remember. If the meal is still being digested (within approximately 1 hour), you can take a reduced dose based on your current blood glucose. Do not take a double dose to make up for a missed injection. If a significant amount of time has passed, simply resume your normal dosing schedule and monitor blood glucose more frequently. Contact your healthcare team if you are unsure how to handle a missed dose.
Overdose
An overdose of Insuman Rapid leads to hypoglycaemia, which can be mild, moderate, or severe. Mild to moderate hypoglycaemia can be treated by consuming fast-acting carbohydrates (glucose tablets, fruit juice, or sugary drinks). Severe hypoglycaemia with loss of consciousness is a medical emergency requiring intramuscular or subcutaneous glucagon injection or intravenous glucose administered by a healthcare professional. Call your local emergency services immediately. Recurrence of hypoglycaemia is possible after initial recovery, so continued monitoring and carbohydrate intake are essential.
What Are the Side Effects of Insuman Rapid?
The most common side effect of Insuman Rapid is hypoglycaemia (low blood sugar), which can occur if the dose is too high relative to food intake and physical activity. Other side effects include injection site reactions, allergic reactions, and changes in subcutaneous fat tissue (lipodystrophy).
Like all medicines, Insuman Rapid can cause side effects, although not everybody gets them. The frequency and severity of side effects depend on factors such as the individual patient, the dose, blood glucose control, and injection technique. Hypoglycaemia is by far the most frequently reported adverse effect and can range from mild symptoms (hunger, tremor, sweating) to severe episodes with loss of consciousness and seizures.
Very Common
- Hypoglycaemia – symptoms include tremor, sweating, palpitations, hunger, dizziness, confusion, pallor, headache, blurred vision, and in severe cases loss of consciousness or seizures
Common
- Injection site reactions – redness, swelling, itching, pain, or bruising at the injection site
- Oedema – fluid retention and swelling, particularly at the start of insulin therapy or after a significant improvement in blood glucose control
- Lipodystrophy – thickening (lipohypertrophy) or thinning (lipoatrophy) of subcutaneous fat at injection sites; prevented by rotating injection sites regularly
Uncommon
- Urticaria (hives) – itchy, raised welts on the skin that may indicate a mild allergic reaction to insulin or its excipients
- Visual disturbances – transient changes in vision (blurriness) related to rapid fluctuations in blood glucose that alter the osmotic balance of the eye lens; usually resolves spontaneously
Rare
- Severe allergic reactions (anaphylaxis) – generalised skin reactions, swelling of the face, tongue, or throat (angioedema), breathing difficulties, drop in blood pressure, and rapid heartbeat. This is a medical emergency requiring immediate treatment
- Sodium retention – insulin may cause sodium retention, which can contribute to fluid overload in susceptible individuals, particularly those with heart failure
- Dysgeusia – metallic or unusual taste in the mouth
- Myalgia – muscle pain
Contact your doctor or go to the emergency department immediately if you experience: signs of a severe allergic reaction (widespread rash, swelling of face or throat, difficulty breathing); severe hypoglycaemia with loss of consciousness or seizures; or persistent, unexplained skin reactions at injection sites. If you suspect severe hypoglycaemia and the patient is unconscious, do not give food or drink – administer glucagon if available and call emergency services.
How Should You Store Insuman Rapid?
Store unopened Insuman Rapid in the refrigerator at 2-8 °C. Once in use, keep at room temperature (below 25 °C) for up to 4 weeks. Never freeze insulin and protect it from direct sunlight and heat.
Proper storage of insulin is essential to maintain its effectiveness. Insulin that has been improperly stored may lose potency without any visible change in appearance, leading to poor blood glucose control. Follow these storage guidelines carefully:
- Unopened (not in use): Store in a refrigerator between 2 °C and 8 °C. Keep the outer carton to protect from light. Place in the main body of the refrigerator, not adjacent to the freezer compartment. Stored correctly, unopened Insuman Rapid is stable until the expiry date printed on the package
- In use (opened): Once a vial has been punctured or a cartridge inserted into a pen, it may be stored at room temperature (below 25 °C) for a maximum of 4 weeks. Keep away from direct heat and sunlight. Do not refrigerate an in-use vial or pen, as cold insulin injections can be more painful and may alter absorption
- Do not freeze: Frozen insulin is permanently damaged and must be discarded. Check that the insulin has not been accidentally frozen during transport or storage
- Visual inspection: Before each injection, inspect the insulin solution. Insuman Rapid should be a clear, colourless liquid with no visible particles. If the solution appears cloudy, discoloured, or contains particles, do not use it
- Expiry date: Do not use Insuman Rapid after the expiry date stated on the carton and label. The expiry date refers to the last day of that month
- Disposal: Do not dispose of insulin in household waste. Used needles, syringes, and cartridges should be placed in an approved sharps container. Ask your pharmacist about local disposal arrangements
What Does Insuman Rapid Contain?
The active ingredient in Insuman Rapid is insulin human, produced by recombinant DNA technology. Each millilitre contains either 40 IU or 100 IU of insulin human, depending on the formulation. The solution also contains several inactive ingredients (excipients).
Understanding the full composition of Insuman Rapid is important for patients with known allergies or sensitivities to pharmaceutical excipients. The complete list of ingredients is as follows:
- Active substance: Insulin human (recombinant DNA origin, produced in Escherichia coli). Available as 40 IU/ml (Insuman Rapid 40 IU/ml) and 100 IU/ml (Insuman Rapid 100 IU/ml)
- Metacresol: Used as a preservative. Patients with known metacresol allergy should not use Insuman Rapid
- Sodium dihydrogen phosphate dihydrate: Buffer to maintain pH
- Glycerol: Tonicity agent to make the solution isotonic
- Sodium hydroxide: pH adjustment
- Hydrochloric acid: pH adjustment
- Water for injections: Solvent
Insuman Rapid is available in several presentations to suit different patient needs and injection devices:
- Vials: 5 ml or 10 ml vials for use with insulin syringes
- Cartridges: 3 ml cartridges for use in compatible reusable insulin pens (e.g., AllStar, AllStar PRO, JuniorSTAR)
- Pre-filled pens (SoloStar): 3 ml pre-filled disposable pens, ready to use. Each pen delivers doses from 1 to 80 IU in steps of 1 IU
Insuman Rapid is available in two concentrations: 40 IU/ml and 100 IU/ml. These are not interchangeable without careful dose recalculation. Always use syringes and injection devices that match the concentration of your insulin. Using the wrong syringe with the wrong concentration can lead to a potentially life-threatening overdose or underdose. The 100 IU/ml formulation is the standard in most countries; the 40 IU/ml formulation is primarily available in certain markets.
Frequently Asked Questions About Insuman Rapid
Insuman Rapid is a fast-acting human insulin used to treat diabetes mellitus in adults, adolescents, and children who require insulin to control their blood glucose levels. It is used for mealtime blood sugar control and can also be administered intravenously in hospital settings for diabetic emergencies such as diabetic ketoacidosis. It is commonly used as part of a basal-bolus insulin regimen, providing the mealtime (bolus) component.
Insuman Rapid begins to lower blood glucose within 30 minutes of subcutaneous injection. The peak effect occurs between 1 and 3 hours after injection, and the total duration of action is approximately 5 to 7 hours. It should ideally be injected 15 to 20 minutes before a meal. When given intravenously in hospital settings, the onset is immediate.
Insuman Rapid contains regular human insulin (soluble insulin) produced by recombinant DNA technology, identical to natural human insulin. Rapid-acting insulin analogues (such as insulin lispro, aspart, or glulisine) are structurally modified insulins with a faster onset (10-15 minutes) and shorter duration. Insuman Rapid requires injection 15-20 minutes before meals, while analogues can be given immediately before or even just after eating. Your doctor will determine which type is most suitable for you.
Insuman Rapid can be mixed with Insuman Basal (isophane insulin) in the same syringe. When mixing, always draw up Insuman Rapid (clear solution) first, then add the cloudy Insuman Basal. The mixture should be injected immediately after preparation. Insuman Rapid must not be mixed with insulins from other manufacturers, with insulin analogues, or with animal-derived insulins. It should also not be mixed with any other medicines.
If you inject too much Insuman Rapid, you may experience hypoglycaemia (low blood sugar). For mild hypoglycaemia, immediately consume fast-acting carbohydrates such as glucose tablets, fruit juice, or a sugary drink. For severe hypoglycaemia with loss of consciousness, do not attempt to give food or drink. Administer glucagon if available and call emergency services immediately. After recovery from severe hypoglycaemia, continued monitoring is essential as blood glucose may drop again.
Unopened Insuman Rapid should be stored in the refrigerator at 2-8 °C, away from the freezer compartment. Do not freeze. Once a vial or pen is in use, it can be kept at room temperature (below 25 °C) for up to 4 weeks. Protect from direct sunlight and heat. Before each injection, check that the solution is clear and colourless with no visible particles. Discard the insulin after 4 weeks of room temperature storage, even if it still contains product.
References
- European Medicines Agency (EMA). Insuman Rapid – Summary of Product Characteristics. EMA/H/C/000411. Available at: ema.europa.eu. Last updated 2024.
- World Health Organization (WHO). WHO Model List of Essential Medicines, 23rd List. Geneva: WHO; 2023. Insulin (human) listed as essential medicine for diabetes management.
- American Diabetes Association (ADA). Standards of Care in Diabetes – 2025. Diabetes Care. 2025;48(Supplement_1):S1-S352. doi:10.2337/dc25-SINT.
- 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. NICE guideline [NG17]. Updated 2022.
- Nathan DM, et al. Management of Hyperglycemia in Type 2 Diabetes: A Consensus Report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD). Diabetes Care. 2022;45(11):2753-2786.
- British National Formulary (BNF). Insulin (soluble). Available at: bnf.nice.org.uk. Accessed January 2026.
- Frier BM. Hypoglycaemia in diabetes mellitus: epidemiology and clinical implications. Nature Reviews Endocrinology. 2014;10(12):711-722. doi:10.1038/nrendo.2014.170.
- Heinemann L. Variability of insulin absorption and insulin action. Diabetes Technology & Therapeutics. 2002;4(5):673-682.
- Bliss M. The Discovery of Insulin. University of Chicago Press; 2007. Historical context of human insulin development.
Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, comprising licensed physicians specialising in endocrinology, diabetology, and clinical pharmacology. All content follows international medical guidelines including the EMA Summary of Product Characteristics, WHO Essential Medicines List, ADA Standards of Care, and BNF prescribing guidance.
iMedic Medical Editorial Team
Specialists in Endocrinology & Diabetology
iMedic Medical Review Board
Independent physician review panel
GRADE Framework
Evidence Level 1A
EMA, WHO, ADA, NICE, BNF
Peer-reviewed journals