Canine Diabetes Wiki
Novolin R
R, Neutral by Novo Nordisk
U100 none
Action in dogs:
  • onset 10-30 minutes,
  • peak 1-5h,
  • duration 4-10h [1]
Line: Novolin
Also known as: Actrapid, ReliOn/Novolin R
Similar to: Huminsulin Normal, Humulin C
Humulin RHumuline R, Humulin Regular
Humulina Regular, Humuline Regular, Humulin S
Humulin ReliOn R, Umuline Rapide
Umuline Regular, Insuman Rapid, Winthrop Rapid

Names of Lilly r-DNA/GE/GM insulins worldwide
Use and Handling:
Shelf Life: 24 months Type: soluble, clear
When Opened: 6 weeks room temp.
In Pen: 6 weeks room temp.
Notes: Protect from light and heat
Do Not Freeze,
May be used intravenously


Novolin R--Regular/Neutral GE insulin.

Novo Nordisk's brand of "R"-action insuln is known by three names: Actrapid [2][3][4] in Europe: ReliOn/Novolin R and Novolin R in North America.

As of January 1, 2010, Novo discontinued offering Novolin R in cartridges for refillable insulin pens. [5][6]

Other companies make similar products--they are: Huminsulin Normal, Humulin R [7][8] and Humulin S [9][10][11] by Eli Lilly and Insuman Rapid [12][13] and Winthrop Rapid both by Aventis.

A short-acting, soluble, non-suspended insulin produced from r-DNA/GE/GM, bovine, or porcine sources. From 1921 to the 1930's when PZI was developed, R was the only kind of insulin available.

While both R/neutral and semilente insulins are considered fast-acting, they differ in a few ways. As above, there's no suspension or buffer [14] in R/neutral; it's totally dissolved and soluble, meaning it can safely be used intravenously. [15]

The very small insulin particles in semilente insulin are suspended by zinc. [16] Semilente is cloudy, has an acetate buffer and cannot be used intravenously.

R/Neutral insulin cannot be reliably mixed with Lente or Ultralente insulins. [17][18]. Semilente can; the ratio of 3 parts semilente insulin to 7 parts ultralente insulin produces Lente insulin [19]

R/Neutral Insulins[]


  1. Insulins. North American Veterinary Conference Clinicians Brief (2006).
  2. Prescribing Novo Insulins.
  3. Scientific Discussion-Actrapid. EMEA.
  4. Patient Information Leaflet-Actrapid. Novo Nordisk.
  5. Novo discontinuation notice for pens. Novo Nordisk.
  6. Novolin R cartridge Discontinuation Notice. US Food and Drug Administration.
  7. Humulin R patient leaflet. Eli Lilly.
  8. Humulin R Regular Human Insulin. Revolution Health.
  9. Patient Information Leaflet-Humulin S. Eli Lilly.
  10. Humulin S Prescribing Information.
  11. Lilly EU/UK Product Information Sheet & Time Activity Profiles. Eli Lilly.
  12. Prescribing Insuman Insulins.
  13. Patient Information Leaflet-Insuman Rapid. Sanofi-Aventis.
  14. DeRuiter, Jack. Insulin Preparations-Regular Insulin. Auburn University.
  15. Maddison, Jill E.,Page, Stephen W.,Church, David B. (2008). Small Animal Clinical Pharmacology. Saunders Ltd..
  16. DeRuiter, Jack. Insulin Preparations-Lente. Auburn University.
  17. Deckert, T. (1980). Intermediate-Acting Insulin Preparations: NPH (Isophane) & Lente. Diabetes Care.
    Note--in 1980, there were no r-DNA/GE/GM insulins
  18. Resource Guide 2005-American Diabetes Association
  19. DeRuiter, Jack. Insulin Preparations-Lente Insulin. Auburn University.

More Information[]

Related Pages
Rtap HumilinLILLY 21944f DSC02818 Actrapid
Humulin ReliOn R
Humulin R
Humulin S
Insuman Rapid