Hello again, My rheumatologist or my dentist have both given me a prescription for it. The dentist has supplied when I didn't have a rheumy since a dry mouth promotes tooth decay. My PCP is worthless and I'm hoping when the dust settles down with the current shakeup, that I can switch to a far better PCP (if I can find one accepting new patients.). Present doc wouldn't be helpful at all when it comes to rheumatology knowledge and proper care.