Canine Diabetes Wiki
Humulin 50/50
R/Neutral/NPH/Isophane Mix by Eli Lilly
U40, U100 isophane
Action in dogs:
  • onset 0.5-3h,
  • peak 2-10h,
  • duration 4-24h
Line: Humulin
Also known as: Huminsulin 50/50
Humulin M5, Humulina 50/50, Humuline 50/50
Similar to: Actraphane 50/50, Mixtard 50, Penmix 50 [1]
Insuhuman Comb 50, Insuman Comb 50
Winthrop Comb 50

Names of Lilly r-DNA/GE/GM insulins worldwide
Use and Handling:
Shelf Life: 24 months Type: cloudy
When Opened: 28 days room temp.
In Pen: 28 days room temp.
Notes: Protect from light and heat
Do Not Freeze, Resuspend
Do not use if product does not re-suspend
Do not use intravenously [2]

Humulin 50/50. This insulin is 50% R/Neutral insulin and 50% NPH/Isophane insulin.

Humulin 50/50 was the US brand name for Lilly's r-DNA/GE/GM human insulin mix consisting of 50% R/neutral insulin and 50% NPH/isophane crystal [3] insulin, [4][5]

It is the same as Humulina 50/50, Humuline 50/50, Mixtard 50, [6] Actraphane 50/50 [7][8] and Aventis' Insuman Comb 50. [9][10] and Winthrop Comb 50

Lilly stopped offering this insulin, under the brand name Humulin M5 [11], in the EU & UK in July 2004.[12][11]

Humulin 50/50 has been discontinued. This notice dated August 12, 2009, indicates there would be a supply of it until April 2010. [13][14][15]

Mixed insulins cover a wide range as they can be animal origin, r-DNA/GE/GM origin or analog insulins. The non-analog mixed insulins are made up of intermediate-acting NPH/isophane insulin and short-acting R/neutral. normal insulin. The analog mixes are made from intermediate-acting protamine-suspended analog insulin (suspended similar to NPH/isophane insulin) and fast-acting analog insulin. They can also vary in the fraction (amount or percent) of the two types (R/neutral and NPH/isophane) of insulin used to make a non-analog mix, and in the percentage of fast/rapid-acting analog insulin and slower-acting protamine suspended analog insulin.

For some reason, those in the US choose to list the slower, NPH/isophane based insulin fraction first, such as Humulin or Novolin 70/30. The rest of the world gives the faster insulin top billing and the result is 30/70. Regardless of how this is written, it means that the insulin is made up of 70% NPH/isophane insulin and 30% R/neutral insulin.

The most common mixes are 70/30 (30/70) (non analog) or 75/25 (25/75) (analog). There are no currently-marketed mixes which combine insulins of different origins. Eli Lilly's form of beef/pork Iletin and Novo Nordisk's Lentard were discontinued some time ago. Here are the most common ones that could cause confusion:


  1. Penmix 50. Medsafe NZ.
  2. Maddison, Jill E.,Page, Stephen W.,Church, David B. (2008). Small Animal Clinical Pharmacology. Saunders Ltd..
  3. Scientific Discussion--Mixtard. EMEA.
  4. Humulin 50/50-NPH;R Human Insulin. Revolution Health.
  5. Patient Leaflet-Humulin 50/50. Eli Lilly.
  6. Insulins & Mixtures. NHS.
  7. Scientific Discussion--Actraphane. EMEA.
  8. Prescribing Novo Insulins.
  9. Patient Information Leaflet-Insuman Comb 50. Sanofi-Aventis.
  10. Prescribing Insuman Insulins.
  11. 11.0 11.1 Lilly EU/UK Product Sheet & Time Activity Profiles. Eli Lilly. Cite error: Invalid <ref> tag; name "Time" defined multiple times with different content
  12. Withdrawal of Humulin M5. Diabetes UK (July 2004).
  13. Humulin 50/50 discontinued.
  14. Discontinuation Notice-Humulin 50/50. Eli Lilly.
  15. Humulin 50/50 Discontinuation Notice. US Food and Drug Administration.

More Information[]

Related pages
Humulin M5
Penfill Mixtard 50 1
Wp comb50 1
Wp comb50 1
Humulin M5
Mixtard 50
Humulina 50/50
Penmix 50