Iletin NPH
NPH/isophane by Eli Lilly
U100 isophane
Action in dogs:
  • onset within 2h,
  • peak 6-12h,
  • duration 18-14h
Line: Iletin
Also known as: Beef NPH, beef isophane
Similar to: Betasint Bovine NPH
Hypurin Bovine Isophane
Use and Handling:
Shelf Life: 36 months Type: cloudy
When Opened: 28 days room temp.
In Pen: N/A
Notes: Protect from light and heat
Do Not Freeze, Re-suspend
Do not use if product does not re-suspend
Do not use intravenously [1]
See Hypurin Bovine Isophane and
Betasint Bovine NPH for current handling notes for bovine NPH insulin.
1975 Lilly JAMA ad

From left-insulins Semilente ("S"), Protamine Zinc ("P"), NPH/isophane ("N"), Regular/neutral/normal ("R"), Lente ("L"), and Ultralente ("U").

Lilly human insulins1992charts

Lilly insulin products-1992. This insulin is shown as Iletin II N.

Note that some countries have the brand name in U40 strength.

A pure beef NPH/isophane suspended insulin formerly made by Eli Lilly.

Like all other isophane/protamine suspended insulins, [2] it was a crystalline suspension with protamine and zinc. [3]

The currently marketed equivalents are Hypurin Bovine Isophane [4][5], made by CP Pharma [6] and Betasint Bovine NPH by Beta Laboratorios.

Specifications of NPH/isophane insulinEdit

British National Formulary [7] defines this type as: A sterile suspension bovine or porcine or of human insulin in the form of a complex obtained by the addition of protamine sulphate or another suitable protamine.

British Pharmacoepia and United States Pharmacopia definitions: [7]

Isophane Insulin

Sterile buffered suspension of insulin in the form of a complex obtained by addition of suitable protamine. Prepared from crystalline insulin. pH 6.9 - 7.5 iso-osmotic with blood. Contains for each 100 units of insulin, 300 - 600 g protamine sulphate and not more than 40 g zinc, a suitable bactericide and sodium phosphate as buffering agent.

USP specification: Sterile suspension of zinc insulin crystalline and protamine sulphate in buffered water for injection. Solid phase contain crystals of insulin protamine and zinc; 40, 80, 100 units/ml. Contains glycerol, metacresol, phenol sodium phosphate and zinc.

NPH/isophane insulinsEdit

The following commercial insulins are all generically NPH insulins:

Other commonly used names are:

  • NPH insulin, NPH
  • isophane insulin


Related pages
Cp wockhardt bovine insulins
Betasint Bovine NPH
Hypurin Bovine Isophane
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