If my mother has either Medicaid or Medicare and has a script for depends, can she get them through mail order?

Ask her Medicaid case worker what suppliers they work with. I don't think you have to use their preferred supplier, but it probably is a little simpler. The products can be delivered every month, or you can call when you need another shipment.

Most Medicaid plans will pay. Medicare will NOT pay.

Most states will pay for incontinence supplies if a person is on MediCAID, not MediCARE.

Medicare doesn't pay for depends. I don't know about Medicaid.