Penmix 20[1]
R/Neutral/NPH/Isophane Mix by Novo Nordisk
intermediate-acting r-DNA/GE/GM
U100 isophane
Line Novo
Also known as Actraphane 20/80[2], Mixtard 20[3]
Similar to Humulin M2
Action in cats  
  • onset Xh,
  • peak Xh
  • duration Xh
Action in dogs  
  • onset 0.5-3h,
  • peak 2-10h,
  • duration 4-24h
Use and Handling
Type cloudy
Shelf Life 30 months
When opened 6 weeks room temp.
In pen 6 weeks room temp.
  • protect from light and heat
  • Do Not Freeze
  • Do not use if product does not re-suspend
  • Roll
  • Do not use intravenously
  • Do not refrigerate in use pens/cartridges.

A mixed, intermediate-acting insulin[4][5] made by Novo Nordisk containing 20% R/neutral insulin and 80% NPH/isophane insulin crystals[6][7].

Comparable product is also made by Novo: Actraphane 20/80[8].

Eli Lilly once produced a similar insulin in the EU & UK called Humulin M2[9]; it was discontinued in July 2004[10].

Another comparable product by Novo, Mixtard 20, was discontinued December 31, 2007.[11][12]


  1. Medsafe NZ Penmix 20
  2. EMEA Scientific Discussion-Actraphane
  3. EMEA Scientific Discussion-Mixtard
  4. Electronic Medicines Compendium (EMC) UK-Patient Information-Mixtard 20
  5. Prescribing Novo Insulins
  6. EMEA Scientific Discussion-Mixtard
  7. Humulin 20/80-NPH;R Human Insulin
  8. EMEA Scientific Discussion-Actraphane
  9. Lilly Product Sheet & Time Activity Profiles
  10. Withdrawal of Humulin M2 July 2004
  11. Insulin Discontinuations-UK
  12. Chart of Discontinued Novo Human Insulins
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