How does this medication work? What will it do for me?

Insulin is a naturally occurring hormone made by the pancreas that helps our body use or store blood glucose (sugar) it gets from food. For people with diabetes, either the pancreas does not make enough insulin to meet the body's requirements, or the body cannot properly use the insulin that is made. As a result, glucose cannot be used or stored properly and accumulates in the bloodstream. Insulin injected under the skin helps to lower blood glucose levels.

There are many different types of insulin that are absorbed at different rates and work for varying periods of time. This type of premixed insulin contains a mixture of fast-acting insulin (insulin regular) and intermediate-acting insulin (insulin NPH). This premixed insulin is used by people with diabetes who have their blood glucose under control and have found a particular ratio of fast-acting to intermediate-acting insulin that works best for them. This premixed insulin starts working 30 to 60 minutes after injection, has its maximum effect between 2 and 8 hours, and stops working after about 18 to 24 hours.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

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What form(s) does this medication come in?


Each mL contains 100 units of insulin (30 units of regular insulin and 70 units of insulin isophane, human biosynthetic - NPH insulin). Nonmedicinal ingredients: disodium phosphate dihydrate, glycerol, hydrochloric acid and/or sodium hydroxide, metacresol, phenol, protamine sulphate, water for injection, and zinc chloride

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Each mL contains 100 units of insulin (30 units of regular insulin and 70 units of insulin isophane, human biosynthetic - NPH insulin). Nonmedicinal ingredients: disodium phosphate dihydrate, glycerol, hydrochloric acid and/or sodium hydroxide, metacresol, phenol, protamine sulphate, water for injection, and zinc chloride.

How should I use this medication?

Your required dose of insulin depends on how much natural insulin your pancreas is producing and how well your body is able to use the insulin. Your doctor or diabetes educator will determine the appropriate dose according to various lifestyle issues and the blood glucose values obtained while monitoring your blood glucose.

Your dose of insulin should be injected subcutaneously (under the skin) exactly as instructed by your doctor or diabetes educator. Do not inject premixed insulin into the vein and do not use premixed insulin in insulin infusion pumps. The dose of insulin is measured in international units (IU). Each mL of insulin contains 100 IU. This premixed insulin is injected about 30 minutes before certain meals. The most common schedule is to use the premixed insulin before breakfast and supper. There are many variations of insulin dosing.

Mix premixed insulin by slowly rolling the bottle or pen between your hands. Premixed insulin suspension should appear cloudy and white. Do not use the insulin if it looks lumpy or grainy, seems unusually thick, sticks to the bottle or vial, or appears discoloured. Do not use the insulin if it contains crystals, if the bottle or vial looks frosted, or if the suspension remains clear after being rolled between your hands.

Keep unopened bottles of insulin in the refrigerator until needed. They may be used until the expiry date on the label. Never allow insulin to freeze. Insulin that is currently in use may be kept at room temperature for no more than 28 days and then discarded. Insulin must not be exposed to extremely hot temperatures or to sunlight. Keep insulin out of the reach of children.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones given here, do not change the way that you are using the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. The timing of insulin with respect to your meals is crucial to keeping blood glucose under control and preventing unwanted side effects.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

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Who should NOT take this medication?

Insulin premixed 30/70 should not be used by anyone who:

  • is allergic to insulin premixed 30/70 or to any of the ingredients of the medication
  • has diabetic coma
  • has low blood glucose (hypoglycemia)
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What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • redness, itching, or swelling at the site of injection

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • signs of low blood glucose:
    • anxiety
    • blurred vision
    • confusion
    • difficulty concentrating
    • difficulty speaking
    • dizziness
    • drowsiness
    • fast heartbeat
    • headache
    • hunger
    • nausea
    • nervousness
    • numbness or tingling of the lips, fingers, or tongue
    • sweating
    • tiredness
    • trembling
    • weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • rash or blisters all over the body
  • seizures
  • symptoms of a serious allergic reaction (e.g., swelling of face or throat, difficulty breathing, wheezing, or itchy skin rash)
  • unconsciousness

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

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Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Allergic reactions: If you notice signs of a serious allergic reaction (swelling of the face or throat, difficulty breathing, wheezing, or itchy skin rash), stop using the medication and seek immediate medical attention.

Appearance of insulin: The contents of the vial of this insulin should be cloudy and white. Do not use the insulin if it looks lumpy or grainy, seems unusually thick, sticks to the bottle or vial, or appears discoloured. Do not use the insulin if it contains crystals, if the bottle or vial looks frosted, or if the suspension remains clear after being rolled between your hands.

Blood glucose monitoring: It is important for anyone using insulin to monitor their blood glucose levels regularly, as recommended by their doctor or diabetes educator. It is especially important to test blood glucose more often when your insulin dose or schedule changes, or when you are ill or under stress. If blood tests consistently show high or low blood glucose levels, contact your doctor or diabetes educator.

Changes at injection site: Fatty tissue under the skin at the injection site may shrink or thicken if you inject yourself too often at the same site. To help avoid this effect, change the site with each injection. Talk to your doctor or diabetes educator if you notice your skin pitting or thickening at the injection site.

Changes in insulin requirements: Many things can affect blood glucose levels and insulin requirements. These include:

  • certain medical conditions (e.g., infections, thyroid conditions, or kidney or liver disease)
  • certain medications that increase or decrease blood glucose levels
  • diet
  • exercise
  • illness
  • injury
  • stress
  • surgery
  • travelling over time zones

It is important your doctor know your current health situation and any changes that may affect the amount of insulin you need. Blood glucose should be monitored regularly as recommended by your doctor or diabetes educator.

Diabetes identification: It is important to either wear a bracelet (or necklace) or carry a card indicating you have diabetes and are taking insulin.

Family and friends: Educate your family and friends about the signs and symptoms of hypoglycemia (low blood glucose). Keep a glucagon kit available and instruct them on its proper use in case you experience severe low blood glucose and you lose consciousness.

Low blood glucose (hypoglycemia): Hypoglycemia may occur if too much insulin is used, if meals are missed, or if you exercise more than usual. Symptoms of mild to moderate hypoglycemia may occur suddenly and can include cold sweat, nervousness or shakiness, fast heartbeat, headache, hunger, confusion, lightheadedness, weakness, and numbness or tingling (tongue, lips, or fingers. Mild to moderate hypoglycemia may be treated by eating foods or drinks that contain sugar. People taking insulin should always carry a quick source of sugar, such as hard candies, glucose tablets, juice, or regular soft drinks (not diet soft drinks).

Signs of severe hypoglycemia can include disorientation, loss of consciousness, and seizures. People who are unable to take sugar by mouth or who are unconscious may require an injection of glucagon or treatment with intravenous (into the vein) glucose. Therefore, contact your doctor if you are pregnant or are thinking about pregnancy.

Pregnancy: It is essential to maintain good blood glucose control throughout pregnancy. Insulin requirements usually decrease during the first trimester and increase during the second and third trimesters.

Breast-feeding: Breast-feeding mothers may require adjustments in insulin dose or diet.

What other drugs could interact with this medication?

There may be an interaction between insulin premixed 30/70 and any of the following:

  • ACE inhibitors (e.g., ramipril, enalapril, lisinopril)
  • alcohol
  • anabolic steroids (e.g., testosterone)
  • beta-blockers (e.g., atenolol, metoprolol, pindolol, propranolol, sotalol)
  • birth control pills
  • certain diuretics (e.g., hydrochlorothiazide)
  • corticosteroids (e.g., prednisone, prednisolone)
  • danazol
  • decongestants (e.g., pseudoephedrine)
  • epinephrine
  • glucagon
  • growth hormone
  • lanreotide
  • MAO inhibitors (e.g., phenelzine, tranylcypromine)
  • octreotide
  • oral medications for diabetes (e.g., gliclazide, glyburide, pioglitazone, rosiglitazone)
  • phenytoin
  • salicylates (e.g., ASA)
  • sulfa antibiotics (e.g., sulfamethoxazole, sulfadiazine)
  • thyroid replacement therapy (if beginning or changing dose)

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.