Insulin aspart, recombinant (Injection)


Insulin Aspart, Recombinant (IN-su-lin AS-part, ree-KOM-bi-nant)

Treats diabetes mellitus. This type of insulin is similar to regular insulin, but acts in the body more quickly.

Brand Name(s)

Novolog, Novolog FlexPen

When This Medicine Should Not Be Used

How to Use This Medicine


  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
  • A healthcare provider should also teach you how to give insulin shots. Make sure you understand how to use the medicine and give yourself the shots.
  • Insulin pump: Keep the pump and pump equipment away from heat and direct light. Heat may increase the temperature of the insulin, and prevent it from working as it should.
  • IV: A nurse or other trained health professional may give you this medicine into a vein if you are in the hospital.
  • When you get a new supply of insulin, check the label to be sure it is the correct type of insulin. Do not change the brand of your insulin unless your doctor tells you to.
  • Use this medicine within 5 to 10 minutes before a meal or right after you eat.
  • Test your blood sugar regularly while you are using this medicine.
  • You will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas.
  • Vial: Use only syringes that are made for insulin injections. Use a new syringe each time you give yourself an injection.
  • Cartridge or pen: Use a new needle each time with this pen. Never share your cartridges with others.
  • Insulin pump: Use insulin aspart by itself. Do not mix it with other insulins. Change the insulin solution in the reservoir of the insulin pump at least every 6 days, and change the infusion set and infusion site at least every 3 days. Make sure your pump is meant for fast-acting insulin. Tell your doctor right away if your insulin pump breaks or leaks. Your blood sugar levels may change rapidly. You may need to give yourself injections until your pump is fixed.
  • If you are mixing insulin aspart and a longer-acting insulin in the same syringe, always draw up insulin aspart into the syringe first. Then draw up the longer-acting insulin.
  • The insulin should look clear and colorless. Do not use insulin aspart if it is cloudy or thickened.

If a dose is missed:

  • Call your doctor or pharmacist for instructions.

How to Store and Dispose of This Medicine

  • Keep all medicine away from heat and direct light.
  • New, unused containers: Store unused vials, pens, or cartridges in the refrigerator. Do not freeze. The medicine may be refrigerated for only 28 days. Throw the medicine away after the expiration date has passed.
  • Containers that are currently being used:
    • Vials: Vials of medicine that you are currently using may be kept in the refrigerator or at room temperature for up to 28 days.
    • Cartridge or pen: Do not refrigerate your cartridge or pen that you are currently using. Store the cartridge or pen at room temperature in a cool place, away from heat and direct light, up to 28 days.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine, containers, and other supplies. Throw away old medicine after the expiration date has passed.
  • Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can change the amount of insulin you need to use and make it harder for you to control your diabetes. Make sure your doctor knows about all other medicines you are using.
  • Make sure your doctor knows if you are also using an oral medicine for blood sugar control (a thiazolidinedione medicine, such as pioglitazone, rosiglitazone, Actos®, Actoplus Met®, Avandia®).
  • Make sure your doctor knows if you are also using medicine that might lower the potassium levels in your blood, such as a diuretic (water pill).
  • Do not drink excessive amounts of alcohol.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding. Tell your doctor if you have kidney disease, liver disease, heart failure, or hypokalemia (low potassium in the blood).
  • Insulin aspart starts to work faster than some other types of insulin, and its effects do not last as long. It should act more like the insulin your body would normally produce. Because the effects of insulin aspart are short-acting, your doctor may also prescribe a longer-acting insulin for you to use.
  • You might sometimes have low blood sugar while you are using insulin. This is more likely if you miss a meal, exercise for a long time, or drink alcohol.
  • You might sometimes have high blood sugar if you miss a dose, do not take enough insulin, overeat or do not follow your meal plan, or do not exercise as much as usual.
  • The use of insulin together with oral diabetes medicines called TZDs (thiazolidinediones) can cause your body to retain too much water. This could make congestive heart failure worse, or it could lead to heart failure. Call your doctor if you have trouble breathing, rapid weight gain, or swelling in your hands, ankles, or feet.
  • Never share insulin pens or cartridges with other people under any circumstances. It is not safe. Sharing needles or pens can transmit hepatitis, HIV, and other blood-borne illnesses.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Dizziness, lightheadedness
  • Dry mouth, increased thirst, muscle cramps, nausea or vomiting, uneven heartbeat
  • Fast or pounding heartbeat, sweating
  • Hunger, trembling
  • Increased thirst
  • Mood changes
  • Rapid weight gain, swelling in your hands, ankles, or feet
  • Trouble breathing, cold sweat, bluish-colored skin
  • Urinating more or more often than normal

If you notice these less serious side effects, talk with your doctor:

  • Blurred vision or trouble seeing
  • Numbness, tingling, or burning pain in your hands, arms, legs, or feet
  • Redness, itching, swelling, or any changes in your skin where the shot is given

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last reviewed on 8/4/2014

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