Protaphane Penfill

What Is Protaphane Penfill and What Is It Used For?

Protaphane Penfill is a 3 ml glass cartridge containing intermediate-acting human NPH insulin (100 IU/ml) for use with Novo Nordisk NovoPen reusable injection devices. It is prescribed to treat diabetes mellitus in adults, adolescents, and children aged 2 years and above, providing basal (background) insulin coverage by lowering blood glucose gradually over up to 24 hours after subcutaneous injection.

Diabetes mellitus is a chronic metabolic disorder characterised by persistently elevated blood glucose levels. In type 1 diabetes, the immune system destroys the insulin-producing beta cells of the pancreas, leading to an absolute deficiency of insulin. In type 2 diabetes, the body becomes resistant to the effects of insulin and the pancreas gradually loses the ability to produce enough to overcome this resistance. Insulin therapy, including basal insulins such as Protaphane Penfill, is essential in type 1 diabetes and is commonly required as type 2 diabetes progresses, as well as in gestational diabetes and certain other secondary forms of diabetes.

Insulin is a protein hormone produced by the beta cells of the pancreas. It facilitates the uptake of glucose from the bloodstream into muscle, liver, and fat cells, where glucose is used as fuel or stored as glycogen and triglycerides. Insulin also suppresses the production of glucose by the liver (gluconeogenesis and glycogenolysis), reduces fat breakdown (lipolysis and ketogenesis), and promotes the synthesis of proteins. Without sufficient insulin activity, blood glucose rises to harmful levels, leading to short-term symptoms such as fatigue, excessive thirst, and frequent urination, and to long-term complications affecting the eyes, kidneys, nerves, heart, and blood vessels.

Protaphane Penfill contains human insulin that is structurally identical to the insulin made by the human pancreas. It is produced using recombinant DNA technology in baker's yeast (Saccharomyces cerevisiae). The designation “isophane” refers to the Neutral Protamine Hagedorn (NPH) formulation, in which protamine sulfate and zinc are combined with insulin to form small crystals. These crystals dissolve gradually after subcutaneous injection, which delays and prolongs the absorption of insulin into the bloodstream. As a result, Protaphane Penfill has a distinctive intermediate time-action profile, markedly different from that of soluble short-acting or rapid-acting insulin analogues.

After subcutaneous injection, Protaphane Penfill begins to lower blood glucose within approximately 1.5 hours. The maximum (peak) blood glucose-lowering effect occurs between 4 and 12 hours, and the total duration of action is up to 24 hours. This pharmacokinetic profile makes the product suitable as a basal insulin, providing background coverage to control fasting and pre-meal blood glucose, to suppress hepatic glucose production overnight, and to maintain stable glycaemic control when combined with rapid-acting or short-acting mealtime insulins.

In clinical practice, Protaphane Penfill is most often used as part of a basal-bolus insulin regimen in type 1 diabetes, typically in combination with a rapid-acting insulin analogue such as insulin aspart (NovoRapid/Novolog) taken immediately before meals. In type 2 diabetes, it may be used as an add-on to oral antidiabetic medicines (such as metformin) when lifestyle and oral therapy alone are insufficient, or it may form part of a more complex combined insulin regimen. Your doctor will determine the most appropriate regimen based on your individual blood glucose targets, lifestyle, diet, physical activity pattern, and overall health status.

The Penfill Cartridge System

The “Penfill” designation refers specifically to the 3 ml glass cartridge format developed by Novo Nordisk for its reusable insulin pens. A Penfill cartridge is loaded into a NovoPen device and stays in place for up to 6 weeks of use (or until empty, whichever comes first). Each cartridge contains 300 IU of insulin at 100 IU/ml and is sealed with a rubber plunger at one end and a rubber septum at the other, which the pen's needle penetrates with each dose. An internal glass ball helps resuspend the NPH crystals when the pen is rolled and tipped before use.

Compared with pre-filled disposable pens such as the FlexPen or InnoLet (which are discarded when empty), the Penfill cartridge system is reusable and can be more cost-effective for long-term users. It is also popular with people who prefer the tactile feedback, click count, or memory features of specific NovoPen models, particularly the NovoPen Echo range, which offers a half-unit dosing increment and a memory function that records the time and dose of the last injection – features that are particularly helpful for children and caregivers.

What Should You Know Before Taking Protaphane Penfill?

Before starting Protaphane Penfill, inform your doctor about all medical conditions you have, all medicines and supplements you take, and lifestyle factors such as alcohol use, exercise habits, and planned travel. Several medical conditions and drugs can alter your insulin requirements, and dose adjustments may be necessary to maintain safe and effective blood glucose control.

Contraindications

Do not use Protaphane Penfill if you are currently experiencing an episode of hypoglycaemia (low blood sugar). Administering additional insulin during hypoglycaemia will drive blood glucose even lower, which can be life-threatening. Wait until your blood sugar has returned to a safe level and you have eaten a carbohydrate-containing meal before resuming your usual insulin schedule.

Do not use Protaphane Penfill if you are hypersensitive (allergic) to human insulin or to any of the excipients in the formulation. The excipients include protamine sulfate, zinc chloride, glycerol, metacresol, phenol, dibasic sodium phosphate dihydrate, sodium hydroxide, hydrochloric acid, and water for injections. Allergic reactions can range from localised skin reactions at injection sites to severe, potentially life-threatening systemic anaphylaxis. Protamine sulfate itself can also cause hypersensitivity reactions in rare cases, particularly in people previously exposed to it (for example, during cardiac surgery).

Protaphane Penfill is for subcutaneous use only. It must never be injected intravenously or intramuscularly. Intravenous injection of an NPH insulin can cause severe, rapid-onset hypoglycaemia. Protaphane Penfill is also not suitable for use in continuous subcutaneous insulin infusion (CSII) pumps, because the protamine suspension can precipitate and block the infusion tubing. If you need pump therapy, your doctor will prescribe a soluble insulin appropriate for pump use, such as a rapid-acting insulin analogue.

Do not use a Protaphane Penfill cartridge in any insulin pen other than those for which it is validated (Novo Nordisk NovoPen and NovoPen Echo ranges). Using a cartridge with an incompatible pen may result in inaccurate dosing, leakage, cartridge damage, or injection failure.

Warnings and Precautions

Several situations may alter how your body responds to insulin and require vigilant monitoring. Insufficient dosing, missed injections, acute illness (particularly with fever), significant overeating, or discontinuation of insulin therapy can all lead to hyperglycaemia and, in people with type 1 diabetes, to diabetic ketoacidosis (DKA). Early warning signs of hyperglycaemia include increased thirst, frequent urination, fatigue, nausea, loss of appetite, flushed skin, and fruity-smelling breath. If these symptoms appear, check your blood glucose and blood or urine ketones and contact your healthcare provider promptly.

Hypoglycaemia is the most common adverse reaction to any insulin, including Protaphane Penfill. It can develop rapidly if the dose is too high for the prevailing insulin requirement, if a meal is skipped or delayed, if exercise is unplanned or especially strenuous, or if alcohol is consumed on an empty stomach. Patients who have had diabetes for many years or who maintain very tight glycaemic control may develop hypoglycaemia unawareness, in which the typical warning symptoms are blunted. This significantly increases the risk of severe hypoglycaemia. Discuss any changes in your ability to detect hypoglycaemia with your diabetes team, as your treatment plan may need adjustment.

Kidney and liver disease can both affect how your body handles insulin. In renal or hepatic impairment, insulin clearance is reduced, which prolongs its action and increases the risk of hypoglycaemia. Dose reductions and more frequent blood glucose monitoring may be needed. Your doctor may also consider less stringent glycaemic targets to reduce the risk of dangerous lows, particularly if you have been hospitalised, are severely unwell, or are approaching the end of life.

Thyroid disease, adrenal insufficiency, and disorders of the pituitary gland can change insulin requirements unpredictably. If you have any of these conditions or start treatment for them, close monitoring of blood glucose is essential. Similarly, significant changes in diet, physical activity, body weight, or psychological stress can alter how much insulin you need. If you are travelling across time zones, work with your diabetes team well in advance to plan dose timing adjustments, and carry a doctor's letter confirming your need to carry insulin and needles in your hand luggage.

Patients with type 2 diabetes who are at cardiovascular risk and take insulin in combination with pioglitazone should be monitored for signs of heart failure. Report any unexpected shortness of breath, rapid weight gain, or swelling of the ankles (oedema) to your doctor immediately. In some cases, discontinuation of pioglitazone may be required.

Pregnancy and Breastfeeding

Maintaining good blood glucose control before conception and during pregnancy is essential to protect both the mother and the developing baby. Poorly controlled diabetes increases the risk of miscarriage, congenital malformations, pre-eclampsia, macrosomia (a large baby), shoulder dystocia during delivery, neonatal hypoglycaemia, respiratory distress, and stillbirth. Protaphane Penfill can be used safely during pregnancy and has a long record of use in pregnant women with diabetes. Human insulin does not cross the placenta in clinically meaningful amounts.

Insulin requirements change dynamically during pregnancy. In the first trimester, insulin needs typically decrease, and the risk of hypoglycaemia is elevated, particularly in women with hyperemesis. During the second and third trimesters, placental hormones increase insulin resistance markedly, and insulin doses usually need to be increased substantially – sometimes doubled or tripled compared with pre-pregnancy requirements. After delivery, insulin requirements often return rapidly to pre-pregnancy levels, and another dose adjustment is required to prevent hypoglycaemia.

If you are planning a pregnancy or are already pregnant, seek specialist advice from a diabetes care team experienced in managing diabetes in pregnancy. Pre-pregnancy counselling, high-dose folic acid supplementation, frequent blood glucose self-monitoring (or continuous glucose monitoring where available), and regular antenatal follow-up are all recommended.

Protaphane Penfill can also be used during breastfeeding. Insulin is a protein and is broken down in the baby's digestive tract, so it is not absorbed in an active form through breast milk. However, breastfeeding increases caloric expenditure and can affect blood glucose levels, and women who breastfeed exclusively often require lower insulin doses than they did before pregnancy. Adjustment of the basal insulin dose may be needed to prevent hypoglycaemia during or shortly after breastfeeding sessions, particularly overnight.

Driving and Operating Machinery

Hypoglycaemia impairs concentration and reaction time and can pose a serious risk when driving or operating machinery. Always check your blood glucose before driving, particularly on long journeys, and do not drive if your blood glucose is low or if you feel any symptoms of hypoglycaemia such as dizziness, shaking, confusion, or sweating. Keep fast-acting glucose (tablets, gel, or a sugary drink) within easy reach in your vehicle. If you experience frequent hypoglycaemia or reduced awareness of warning signs, discuss with your doctor whether it is safe for you to drive, and follow the licensing regulations in your country. Many jurisdictions require people with insulin-treated diabetes to notify their driving licensing authority.

Use in Children

Protaphane Penfill can be used in children aged 2 years and above. The NovoPen Echo and NovoPen Echo Plus are particularly suitable for paediatric use because they allow dosing in 0.5-unit increments and display the time since the last dose, reducing the risk of double-dosing and helping caregivers coordinate insulin administration. In very young children, the total daily dose may be small, and accuracy of each dose becomes critical. Paediatric endocrinologists may adjust the dose distribution between basal and bolus insulin based on growth, pubertal stage, and meal-time patterns.

How Does Protaphane Penfill Interact with Other Drugs?

Many medications can alter the blood glucose-lowering effect of Protaphane Penfill. Some increase the risk of hypoglycaemia, while others reduce insulin's effectiveness and may cause hyperglycaemia. Always tell your doctor and pharmacist about every prescription medicine, over-the-counter product, herbal remedy, and supplement you use, so that insulin doses can be safely adjusted.

Drug interactions with insulin are clinically important because they can shift glucose control in either direction. Some medications potentiate insulin's hypoglycaemic effect, increasing the risk of dangerously low blood sugar. Others antagonise insulin, contributing to hyperglycaemia and poor diabetes control. A third category – including some beta-blockers – may mask the adrenergic warning symptoms of hypoglycaemia, making it harder to recognise and treat low blood sugar promptly.

Major Interactions

The following medications have the most clinically significant interactions with Protaphane Penfill. Dose adjustments are frequently required when starting, stopping, or changing the dose of any of these drugs:

Additional Interactions and Cautions

Other medications also deserve attention. Sympathomimetics (such as adrenaline/epinephrine, salbutamol, and terbutaline), growth hormone, danazol, and atypical antipsychotics such as olanzapine and clozapine can raise blood glucose and reduce the effectiveness of insulin. Octreotide and lanreotide may either increase or decrease insulin requirements unpredictably and require frequent monitoring. Pioglitazone combined with insulin increases the risk of fluid retention and heart failure in susceptible patients.

Beta-Blockers: A Special Consideration

Beta-blockers (such as propranolol, atenolol, bisoprolol, or metoprolol) warrant particular attention because they can both alter blood glucose and mask the typical adrenergic warning signs of hypoglycaemia. Specifically, beta-blockers may suppress the tachycardia and tremor that many people rely on to detect falling blood sugar. Sweating, however, is mediated by cholinergic rather than adrenergic pathways and is usually preserved. If you are prescribed a beta-blocker alongside Protaphane Penfill, monitor blood glucose more frequently and learn to recognise non-adrenergic symptoms of hypoglycaemia such as confusion, difficulty concentrating, visual disturbances, and excessive hunger. Cardioselective beta-blockers (such as bisoprolol and metoprolol) tend to interfere less with hypoglycaemia recognition than non-selective agents, but caution is still warranted.

Thiazolidinediones, somatostatin analogues, and atypical antipsychotics can also have variable effects on insulin sensitivity. Cannabis and herbal products (including St John's wort, ginseng, and chromium) can affect glucose control in some patients. Always inform your diabetes team about any complementary or alternative medicines you take.

What Is the Correct Dosage of Protaphane Penfill?

The dose of Protaphane Penfill is strictly individualised based on your blood glucose levels, type of diabetes, other medications, diet, body weight, and level of physical activity. Your doctor will calculate and titrate the dose based on regular blood glucose monitoring and HbA1c results. Never adjust your dose without medical guidance.

Insulin dosing is one of the most individualised aspects of diabetes therapy. There is no single correct dose of Protaphane Penfill – your healthcare team will determine the dose that best controls your blood glucose based on home blood glucose readings (or continuous glucose monitoring), structured self-monitoring, and periodic laboratory tests such as HbA1c. Dosing depends on the type of diabetes, concurrent use of other insulins and oral antidiabetic medicines, body weight, diet, exercise, illness, and individual sensitivity to insulin. The information below is for educational purposes and should not replace the dosing guidance given by your doctor.

Adults

Children and Adolescents

Elderly Patients

How to Prepare and Inject Protaphane Penfill

Protaphane Penfill must be resuspended before every injection so that the insulin is evenly distributed throughout the liquid. Injecting an inadequately mixed suspension can result in significant under- or overdosing. Follow these steps carefully:

1. Wash your hands and prepare a clean injection site. Check the label on the cartridge to confirm you have the correct insulin, strength, and expiry date.
2. Load the cartridge into your NovoPen device following the manufacturer's instructions, if you have not already done so. Never attempt to refill a used cartridge.
3. Resuspend the insulin: Roll the pen (with the cartridge inside) gently between your palms 10 times. Then tip it upside down and back 10 times. The glass ball inside the cartridge will help mix the suspension. The liquid should appear uniformly cloudy and white. Do not use the insulin if it looks clear, if it contains lumps, or if white particles remain stuck to the walls or bottom of the cartridge.
4. Attach a new needle (NovoFine or NovoTwist) and prime the pen by dialling 2 IU, holding the pen with the needle pointing upward, and pressing the injection button until a drop of insulin appears at the needle tip. Repeat priming if no drop appears.
5. Dial your prescribed dose carefully. Check the dose window before injecting. Use the audible or tactile clicks as confirmation if your pen provides them.
6. Choose and clean the injection site: The abdomen, thigh, buttock, or upper arm are all acceptable. Rotate within each area to prevent skin changes. Cleaning is usually with a dry tissue or alcohol swab, as advised by your healthcare provider.
7. Inject subcutaneously: Pinch the skin if recommended and insert the needle at the angle your nurse has shown you. Press the injection button fully and keep the needle under the skin for at least 6 seconds after the dose counter returns to zero, to ensure the full dose is delivered.
8. Remove the needle carefully and dispose of it in a sharps container. Replace the pen cap. Never share pens, cartridges, or needles with another person, even if the needle has been changed – this carries a risk of blood-borne infection transmission.

Missed Dose

If you miss a dose of Protaphane Penfill, your blood glucose may rise. Measure your blood glucose as soon as you remember and follow your diabetes care team's sick-day or missed-dose guidance. In general, do not take a double dose to make up for a missed injection, as this can cause hypoglycaemia. If you are unsure how to manage a missed dose, contact your diabetes specialist nurse, doctor, or pharmacist for advice. The NovoPen Echo and NovoPen 6 display the time since the last injection, which can help you decide whether to take a missed dose or wait until the next scheduled injection.

Overdose

What Are the Side Effects of Protaphane Penfill?

Like all medicines, Protaphane Penfill can cause side effects, although not everyone experiences them. Hypoglycaemia (low blood sugar) is by far the most common side effect and the main clinical risk. Local reactions at injection sites, skin changes, oedema, and rare systemic allergic reactions are also possible. Understanding these risks helps you recognise and manage them promptly.

The adverse effects of Protaphane Penfill are largely shared with other insulin preparations and relate to the pharmacological action of insulin itself and the subcutaneous mode of administration. The most clinically important adverse reaction is hypoglycaemia, which can range from mild and easily self-treated to severe and life-threatening. Frequencies below are based on pooled clinical trial and post-marketing data for human NPH insulins.

If you experience any signs of a systemic allergic reaction (widespread rash, difficulty breathing, swelling of the face, lips or throat, rapid heartbeat, drop in blood pressure, or fainting), seek emergency medical attention immediately. These reactions are extremely rare but can be life-threatening.

Oedema (swelling of the ankles, feet, or hands due to fluid retention) can occur, particularly when insulin therapy is initiated or intensified after a long period of poor glycaemic control. This is usually temporary and resolves as the body adjusts to improved glucose control. Temporary blurred vision may also occur during the first days or weeks of insulin therapy because lens hydration changes with blood glucose levels; no optical prescription change is usually needed, and vision normally stabilises within a few weeks.

Managing Hypoglycaemia

Hypoglycaemia occurs when blood glucose falls below approximately 3.9–4.0 mmol/L (70–72 mg/dL). Common causes include taking too much insulin, skipping or delaying meals, exercising more than usual, drinking alcohol, being unwell (particularly with vomiting or diarrhoea), or injecting into a site with altered absorption (such as a lipohypertrophic lump).

For mild to moderate hypoglycaemia, follow the “15–15 rule”:

1. Immediately consume 15–20 grams of fast-acting carbohydrate (e.g. 3–4 glucose tablets, 150 ml fruit juice, or a small sugary drink).
2. Wait 15 minutes and recheck your blood glucose.
3. If still below target, repeat the fast-acting carbohydrate.
4. Once blood glucose normalises, eat a longer-acting carbohydrate snack (sandwich, biscuits, fruit) to prevent recurrence, especially if the next meal is more than an hour away.

Severe hypoglycaemia – characterised by confusion, loss of consciousness, or seizures – is a medical emergency. It requires immediate glucagon injection by a trained companion and contact with emergency services. Every person using insulin should carry an identification card or medical alert bracelet stating that they have diabetes and use insulin, and should ensure that family, close friends, and colleagues know how to recognise and respond to severe hypoglycaemia.

Managing Hyperglycaemia and Diabetic Ketoacidosis

Hyperglycaemia (high blood sugar) can occur if you miss insulin doses, take less than prescribed, eat significantly more than your meal plan allows, are acutely unwell, or are under stress. Symptoms develop gradually over hours or days and include increased thirst, frequent urination, fatigue, drowsiness, loss of appetite, flushed face, fruity-smelling breath, nausea, and vomiting.

In people with type 1 diabetes, untreated hyperglycaemia can progress rapidly to diabetic ketoacidosis (DKA), a life-threatening condition. DKA is characterised by deep, rapid breathing (Kussmaul breathing), a fast pulse, severe dehydration, and abdominal pain. It requires immediate medical treatment with intravenous fluids, insulin, and electrolyte replacement. If you develop symptoms of DKA or if your blood or urine ketones are significantly elevated, seek emergency medical care without delay.

How Should You Store Protaphane Penfill?

Correct storage of Protaphane Penfill is essential to preserve its effectiveness. Unopened cartridges should be refrigerated at 2–8°C away from the cooling element. Once loaded into a NovoPen for use, the cartridge should be kept at room temperature below 30°C and used within 6 weeks. Never freeze insulin and never store the in-use pen in the refrigerator.

Keep Protaphane Penfill out of the sight and reach of children at all times. Store unopened cartridges in a refrigerator at 2–8°C (36–46°F). Place them in the main body of the refrigerator rather than against the back wall or in the freezer compartment. Never freeze insulin; frozen insulin loses its effectiveness and must be discarded. If a cartridge has been accidentally frozen, do not attempt to use it even after thawing – the crystal structure is irreversibly damaged.

The cartridge that is currently loaded in your NovoPen for use should be stored at room temperature, not exceeding 30°C (86°F), and should be used within 6 weeks of first use (always check the specific product leaflet, as in-use periods may be updated). Do not return the in-use pen with the cartridge to the refrigerator, as temperature fluctuations can affect dose consistency, promote crystal formation, and cause air bubbles to form in the cartridge.

Protect insulin from direct heat, direct sunlight, and extreme cold. Do not leave it in a hot car, on a windowsill, or on top of heating appliances. Do not carry Protaphane Penfill in checked luggage when flying, because the cargo hold can reach freezing temperatures; carry it in your hand luggage along with a doctor's letter confirming your medical need. When travelling in hot climates, use an insulated pouch or a cooling wallet (such as Frio) to keep your insulin within the recommended temperature range. Many cooling wallets use evaporative cooling and do not require refrigeration or ice.

Before each injection, inspect the suspension visually. After proper resuspension, Protaphane Penfill should look uniformly cloudy and white. Do not use it if the suspension contains lumps, if solid white particles stick to the bottom or walls of the cartridge giving a frosted appearance, or if the product fails to become uniformly cloudy after gentle mixing. Once clumping has occurred, the cartridge should be discarded.

Always check the expiry date printed on the cartridge label and carton before use. Do not use Protaphane Penfill after the expiry date, which refers to the last day of the stated month. Dispose of expired or empty cartridges and used needles according to local regulations – do not throw them in household waste or flush them down the drain. Many pharmacies and diabetes clinics offer sharps and medicine disposal services. Ask your pharmacist for local guidance. Used needles should always go into an approved sharps container to protect waste handlers from needlestick injuries.

What Does Protaphane Penfill Contain?

Protaphane Penfill contains human insulin as its active substance, produced using recombinant DNA technology in yeast, at a strength of 100 IU/ml. It also contains several excipients that extend the duration of action, buffer the pH, prevent microbial growth, and maintain the correct tonicity. Each Penfill cartridge holds 3 ml of suspension, providing a total of 300 IU of insulin.

The active substance is human insulin (rDNA origin), produced in the baker's yeast Saccharomyces cerevisiae using recombinant DNA technology. The resulting insulin molecule is structurally identical to the insulin produced by the human pancreas, distinguishing it from older animal-derived (bovine or porcine) insulin preparations that are now largely obsolete. Each millilitre contains 100 international units (IU) of human insulin.

The other ingredients (excipients) in Protaphane Penfill are:

• Protamine sulfate – forms crystalline complexes with insulin to delay absorption and extend the duration of action (this is what makes it an “NPH” insulin)
• Zinc chloride – stabilises the insulin hexamer structure
• Glycerol – tonicity agent that keeps the solution isotonic with body tissues
• Metacresol – antimicrobial preservative
• Phenol – antimicrobial preservative
• Dibasic sodium phosphate dihydrate – buffering agent to maintain pH stability
• Sodium hydroxide – used during manufacture for pH adjustment
• Hydrochloric acid – used during manufacture for pH adjustment
• Water for injections – solvent

Each Penfill cartridge contains 3 ml of suspension, equivalent to 300 IU of insulin at 100 IU/ml. The cartridge itself is made of colourless, neutral type I glass and incorporates a rubber plunger at one end and a rubber-sealed septum at the other. A small glass ball inside the cartridge aids in mixing the suspension before each injection. Pack sizes typically contain 5 or 10 cartridges, though pack sizes may vary by country. Protaphane Penfill contains less than 1 mmol sodium (23 mg) per dose and is therefore considered essentially sodium-free.

Protaphane Penfill is manufactured by Novo Nordisk A/S, a Danish pharmaceutical company with more than 100 years of experience in insulin production. Novo Nordisk developed the first NovoPen in 1985 and has continuously refined the pen and cartridge ecosystem since. Protaphane is approved in many countries worldwide and may be marketed under slightly different brand names in different regions (for example, Insulatard Penfill in some markets). Always verify the name and strength of your insulin when it is dispensed, and make sure the cartridge is compatible with the pen device you have been trained to use.

Frequently Asked Questions About Protaphane Penfill