The first person believed to have successfully administered insulin was MacKenzie Wallis, a British doctor who had learnt from his work in India a great deal about diabetes. He rejected the use of rabbits to screen insulin batches, instead using the test tube method, and treated the first patient within days of the attempts by Banting and Best to treat a 14 year old boy .

Unfortunately because of the preoccupation with animal testing for insulin . animal extracted insulin became dominant . A great deal of resources and time focussed on animal use and extracting insulin from them. Although cow and pig insulin work, their use often resulted in severe allergic reactions because of the simple fact that they are protein foreign to the human body.

By the 1980s the pharmaceutical companies discovered that insulin can also be made by taking human pancreatic cells and reproducing them in bacteria to produce human insulin in laboratories. This insulin which is “ artificial insulin “ is now on sale along with “ natural insulin “ which is the insulin from cows and pigs. But most people do not know the difference leaving the choice to their doctors.

In fact most pharmaceutical companies would be happy to stop animal based insulin as they say genetically engineered insulin more closely resembles insulin made by the human pancreas. But there are many people in the West who insist that they prefer the pancreas of cows and pigs to their own. In fact some diabetics in Canada have gone to court for their right to use it. Since Canadian companies El Lilly and Co and Novo Nordisk have stopped producing animal based insulin, many people in Canada import it from countries in Asia which are still making cow and pig pancreas insulin.While most American companies do not make animal based insulin, European ,British and Indian companies do.