II. Indications
- 
                          Diabetes Mellitus with very high Insulin Resistance- Indicated for those with very high Insulin requirements (>200 units per day)
 
III. Mechanism
- See Insulin
- Humulin R U-500 is a Regular Insulin that is at 5-fold higher concentration than typical Regular Insulin
- At this very high concentration, Humulin R U-500 has Pharmacokinetics that are more like Basal insulin- Despite being Regular Insulin, U-500 acts more like NPH or Insulin 70/30
 
IV. Medications
- 
                          Humulin R U-500 (500 units/ml, green)- Caution: This is 5-fold higher than standard Regular Insulin (U-100, at 100 units/ml)
- High risk for dosing errors (very concentrated Insulin)- Specific U-500 green capped syringes are available as of 2016 to reduce dosing errors
- Pens are preferred for less dosing errors over vials and syringes- Use pen dosing window (not the number of clicks to determine dose)
- Each click of a U-500 pen adds 5 units of Insulin (contrast with 1 unit/click with U-100)
 
 
 
V. Dosing
- See Insulin Dosing
- See Insulin Dosing in Type I Diabetes
- See Insulin Dosing in Type II Diabetes
- Divide dosing twice (60 and 40%) to three times (e.g. 40, 30 and 30%) daily
- Do not combine with other Insulins (i.e. stop basal and mealtime Bolus Insulins)- Use in similar fashion to 70/30 Insulin
 
VI. Pharmacokinetics
- Activity is similar to Insulin 70/30
- Onset: 30 minutes
- Duration: >12 hours- Far longer duration than other Bolus Insulins (more like NPH Basal insulin)
 
VII. References
- (2022) Presc Lett 29(3): 14
