Let's take a minute to talk about your medication. 

This insulin is Humulin-R U-100. 'R' means it is 'regular' or 'short-acting' insulin. U-100 means there are 100 units in every ONE milliliter. 

You should use Humulin-R exactly as prescribed. You need to feel confident with your training on insulin injections. If you have any questions, your doctor or pharmacist can help. 

Humulin-R helps keep blood sugar at healthy levels in patients with diabetes. This may prevent or postpone serious health problems. It treats the natural increases in blood sugar that happen after eating. After your dose, you must eat a meal within 30 minutes to avoid low blood sugar. 

Low blood sugar might make you feel poorly, and it could also reduce your concentration and reaction time. Or, you may not have any warning signs. You should be aware of how it affects you before doing activities that require you to be alert, like driving. You can help prevent low blood sugar by not skipping meals and not exercising too much. You should also tell your doctor when you are sick or stressed. Mild low blood sugar is treated by eating or drinking things that contain sugar. Examples include hard candies and glucose tablets. It is a good idea to always have these available. Blood sugar that is very  low or high  may require emergency help. Make sure you discuss a plan with your doctor, and know when to check your blood sugar. 

You should store unopened vials in the refrigerator. The vial you are using can be kept at room temperature. Once you use a vial, you must throw it away after 31 days. 

For best results with Humulin-R, you should read the Patient Information inside the box. Also, always double-check that you have the right insulin and the right dose.