When do you typically check vitamin B5 levels in patients with peripheral neuropathy?

I do order B5 level in people with burning feet and sometimes the result does show low level. I usually prescribe Sublingual vitamin B complex and folic acid as most of the time if a person is deficient in one, then they can have multiple vitamin deficiency, and we are not checking all in usual clin...

All my patients are on a B-100 complex vitamin 2-3 days a week-they are good for your brain and nerves.