My Friends GSD has HD and EPI, she buys all her treatment from the vets

however her pet insurance has just put her excess up to £70,



and her currently monthly medical bill is approx £150, so she is going to find it tough
When I was speaking to her today I suggested she brought her food and drugs somewhere else, She currently buys prescription hills dog food and the tablets to treat the EPI from the vets, I suggested that she buys the pet shop hills and give raw pigs pancreas.........would this do the same as the prescription ?????
Also where could she buy her cosequin (sp) DS and metacam cheaper