Insulin (18)


isc foodexerciseFactors such as diet, exercise, alcohol use, and illness can affect your blood sugar.  This makes using insulin more complicated. It is important to think about how changes in diet, exercise, alcohol use, and illness may affect the amount of insulin needed to control your blood sugar.

Insulin lowers blood sugar levels. If something increases your blood sugar, you may need more insulin. It is important to talk to your doctor and pharmacist about changes in your diet, exercise, and alcohol use, and any illnesses that you experience. When people feel sick, they often do not eat very much. This means you may not need as much insulin. If you eat more, you may need more insulin. If you exercise more, you may need less insulin. If you drink more alcohol, this may cause your blood sugar to lower.

isc patientpharmacistYour doctor and pharmacist will discuss steps you need to follow to maintain good blood sugar levels. Your doctor and pharmacist will also discuss how often you will need to check your blood sugar.  Be sure to ask for guidance on how to keep good blood sugar levels and ask how often and when you should check your blood sugar.

Sometimes your blood sugar may get too low or too high.

Low blood sugar can be very dangerous.

To prevent dangerous low blood sugar, here are some important tips:

  • Check your blood sugar often.  Talk to your doctor about how often and what time of day to create your own schedule.
  • Watch out for clues
    • Low blood sugar clues include: irritability, shaky hands, being tired, confusion, headache, heart racing, sweating, pale skin, feeling nervous, cold hands and feet, mood swings, crying spells, depression.
    • Usually, blood sugar is too low if less than 70 (mg/dL).
  • Make sure friends and family also know the clues for low blood sugar. When your blood sugar gets too low, you may be too confused to remember what to do.  It's important that friends and family know when you need help fixing low blood sugar.


 If your blood sugar is less than 70 (mg/dL), OR if you have clues of low blood sugar (see above), take action!


  • Drink a glass of orange juice.
  • Drink a glass of regular soft drink or soda (NOT DIET soda).
  • Eat jelly or jam (NOT SUGAR-FREE jelly)
  • Eat candy (NOT SUGAR-FREE candy)
  • Eat 3 sugar pills.


High Blood Sugar

High blood sugar can be very dangerous also. It may take a long time for you to notice the bad effects of high blood sugar, or you may start to feel sick right away.


  • Emergency: If not treated with diet, exercise, and medicine, high blood sugar can lead to "diabetic coma" and death.
  • Long-Term Disability: If not treated with diet, exercise, and medicine, high blood sugar can lead to heart disease, kidney disease, worsening vision, blindness, loss of feeling in hands and feet, impaired healing of cuts and wounds, tingling and damaged nerves, change in bowel movements and constipation. 

To prevent dangerous high blood sugar, here are some important tips:

  • Check your blood sugar often. Talk to your doctor about how often and what time of day to create your own schedule.
  • Watch out for clues.
    • HIgh blood sugar clues include:
      • Drowsy, sleepy, tired
      • Flushed skin
      • Fruit-like breath odor
      • Frequent urination
      • Dry mouth, Dry skin
      • Loss of appetite, Stomach Ache, Nausea, Vomiting
      • Trouble breathing (rapid and deep)
      • Increased blood sugar level
      • Usually, blood sugar is too high if greater than ______ (mg/dL).
  • Make sure friends and family also know the clues for high blood sugar. When your blood sugar gets too high, you may be too confused to remember what to do.  It's important that friends and family know when you need help fixing high blood sugar.

If your blood sugar is greater than ______ (mg/dL), OR if you have clues of high blood sugar (see above), take action!


  • Call your doctor or pharmacist.
  • Develop an action plan for high blood sugar. This includes knowing how much extra insulin to take based on the blood sugar number.

img vial syringeHumulin R is the brand name for Eli Lilly's recombinant human regular insulin. The usual version of Humulin R is U-100 and contains 100 units of insulin activity per 1 milliliter of fluid. But there's also a rarely-used version called U-500. The U-500 insulin is 5 times more potent than U-100 insulin. U-500 insulin contains 500 units of insulin activity per 1 milliliter of fluid. People may need to use U-500 if their diabetes is not well-controlled with U-100. The U-500 version should be used only for patients requiring doses above 200 units a day.

Important information about U-500 insulin

Since the use of U-500 insulin is not as common as the use of U-100 insulin, some health professionals may not be aware of it. This by itself increases the chance of dispensing errors.

The main problem with U-500 insulin is the risk of a mix-up between the insulin U-100 and insulin U-500 versions. If this occurs, it can result in very dangerous low blood sugar or very high blood sugar. A mix-up between the two insulin concentrations may occur if doctors or pharmacists select the wrong concentration (for example, selecting the U-500 regular insulin from computer screen instead of U-100). Sometimes the two concentrations appear one line apart on the computer screen, which sets up the possibility of selection errors. Depending on the screen size, the prescriber may see only the first few words of the product listing, so the drug concentration is not seen. Prescribers may assume the patient needs U-100 and may not even look for the concentration on the screen.

A mix-up may also occur if U-100 insulin and U-500 insulin are stored next to each other at the pharmacy, in the hospital or even in your home. Although the colors of the vials are different, if someone is not aware to look out for the concentration on the vials, the vials could be confused for one another.

U-500 insulin syringe

As of November 2016, a new syringe to administer concentrated Humulin R U-500 (insulin regular) has been made available from the manufacturer, BD. The syringe measures U-500 insulin doses ranging from 25 units to 250 units in 5-unit segments. Prior to the release of the U-500 syringe, it was recommended to use a U-100 syringe or tuberculin syringe to administer U-500 insulin. But dosing errors frequently occurred to patients who drew doses from a vial into a U-100 or tuberculin syringe. Every unit on the U-100 syringe scale is equal to 5 units of U-500 insulin. So, a dose measuring “40” units in a U-100 syringe is really 200 units of U-500 insulin. With a tuberculin syringe, the U-500 insulin dose has to be measured in mL, not units. Both situations have led to serious insulin dosing errors.

Now that a U-500 syringe is available, a U-100 syringe or tuberculin syringe should no longer be used to administer U-500 insulin in healthcare facilities or in the home.

Humulin R U-500 is also available in a prefilled pen, which also measures the concentrated insulin in 5-unit segments. With the Humulin R U-500 KwikPen, and now with the U-500 insulin syringe, the actual dose of U-500 insulin prescribed is the actual dose that is measured in the syringe or dialed with the pen. The updated information for physicians who prescribe Humulin R U-500 now requires all prescriptions for the U-500 insulin vials to be accompanied by prescriptions for the new U-500 insulin syringes. The updated information also recommends that healthcare providers:

  • Instruct patients who use vials of U-500 to use only a U-500 insulin syringe
  • Teach patients how to correctly draw the prescribed dose into the U-500 insulin syringe
  • Confirm that the patient has understood the directions If you are uncertain how to use the new syringe, ask your pharmacist, doctor, or office nurse.

If you are uncertain how to use the new syringe, ask your pharmacist, doctor, or office nurse.

Other Recommendations

Individuals who use insulin must be aware of the concentration and insulin type that you normally use. If you see U-500 on the label when you are supposed to be getting U-100, or if the opposite is true, make sure you question your pharmacist or doctor before taking it.

Also, if another individual in your home also uses insulin that is not the same concentration as yours, store the insulin in different areas. This way you will not inadvertently grab the wrong vial.

If you are to be hospitalized and you use U-500 insulin, be sure to clarify this with the medical staff. It is recommended to bring whichever syringe you use at home to the hospital and demonstrate where you normally draw up your insulin to.

If you need to be hospitalized

isc patientinhospIf you are someone who requires insulin, one of the most important things you can do to stay safe is to have an emergency plan in the event you become ill and need to be hospitalized. In preparing for such an emergency, it's important to take into consideration that you may be too ill to speak for yourself at this time. Therefore, you should always designate another individual who can assist in this process, as needed.

If you are hospitalized, or admitted for any emergent situation, it will be very important for you to tell your doctor and nurse the type of insulin you take, what dose and how you are taking insulin. You should carry an updated list of all medications you take with you at all times. Ideally, it is safest to bring your medications and insulin delivery system into the hospital to prevent any misunderstandings.

It will also be helpful to inform the health care team of your recent blood sugar readings. However, keep in mind, your usual insulin requirement may change with possible illness or emergent care. Be prepared for potential changes in your insulin regimen, which may be needed during your condition and as determined by your doctor.

During your hospitalization or for emergency care, you (or whomever you have designated) will need to pay close attention to your care. Here are some additional tips to avoid errors with your insulin during hospitalization:

  • Be sure the nurse confirms your identity with two identifiers before any insulin injection. For example, calling you by your first name and checking your arm band. Never accept an insulin injection without the nurse checking you identification band or scanning it if the hospital uses bar coding. Your identification band must always be legible.
  • Have the nurse confirm the type and dose of insulin prior to injection. Also request to visualize the syringe to confirm the amount of units in the syringe.
  • Keep accurate documentation of your blood sugar results. This can serve as a double check in the event a nurse either brings you insulin you did not need, or forgot to administer insulin you did need. Keeping documentation of your blood sugar results can also protect you from getting your roommate's dose instead of yours.
  • If the hospital is using an insulin pen, be sure a label is affixed to the pen with only your name. Insulin pens must never be used for more than one patient. Ask the nurse about this.
  • Keep in mind that some hospitals allow and even encourage patients who are experienced in using insulin at home to self administer their own insulin while hospitalized. If you are comfortable doing this, it is good opportunity for you to maintain control of your own insulin and ensure you are receiving your insulin in a timely manner.
  • If you have special equipment you use to take your insulin, such as a pen or a pump, never assume others will know how to use it. Always try to go over instructions for use with a nurse before surgery or hospitalization. Teach a family member or friend how to use the equipment in case you are too sick or unable to explain it.  
  • During hospitalizations, there may be procedures when you are required not to eat anything. If this occurs, your insulin will likely need to be adjusted or held. Unfortunately, there have been instances when nursing staff have continued insulin injections in error, despite a patient not eating. 
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