вы можете использовать IComparer
public class CustomEqualityComparer : IEqualityComparer<vClientMedication>
{
#region IEqualityComparer Members
public bool Equals(vClientMedication x, vClientMedication y)
{
if ((x.BrandName == y.BrandName))
return true;
else
return false;
}}
, а затем написать свой запрос
medication = objectContext.vClientMedication.Distinct(new
CustomEqualityComparer()).ToList();