Your post sent me on a search so I've put in my steps.
I found these papers.
Successful management of allergy to the insulin
excipient metacresol in a child with type 1 diabetes:
a case report. This said as you have been told said that there are no available insulins without m cresol.
http://www.jmedicalcasereports.com/cont ... -6-263.pdf
I
Successful desensitization with human insulin in a patient with an
insulin allergy and hypersensitivity to protamine:
http://www.biomedcentral.com/content/pd ... -2-283.pdf
This one had a list of insulins and ingredients.
There were 2 that didn't mention m. cresol.
The first Berlinsulin H normal© on further research seems to contain it.
The second Insulin Novo semilente
This has been discontinued but I found a pet diabetes site which suggested that lente, semi lente and ultra lente insulins don't (can't) contain m cresol.
http://petdiabetes.wikia.com/wiki/Preservatives
It also seems that Novo Monotard also dosesn't (didn't) have any: This seems to have been withdrawn in most places but I found mention of it on an Indian site but that maybe out of date.
I then went to the Wockhardt site
http://www.wockhardt.co.uk/products/pro ... ductid=358
I found 2 insulins with no mention of m.cresol. (the others did)
Hypurin® Bovine Lente 100 IU/ml injection
excipients:
Sodium chloride
Sodium acetate
Methylparahydroxybenzoate
Zinc oxide
Water for injections
Hydrochloric acid
Sodium hydroxide
Hypurin® Bovine Protamine Zinc Insulin
excipients
Protamine sulphate
Zinc chloride
Glycerol
Sodium phosphate
Phenol
Water for injections
I wouldn't take this as gospel but it would be worth contacting the company.