I Have Just Started Taking Zero Dollars Sp For Chronic

I have just started taking zero dollars sp for chronic back pain, have hard rods inserted three years ago successful but lately back pain has crept in. My question is I take only one tablet a day and it really works, I am walking in the morning for half hour excercise my quality of life is so much better I take Telma h for blood pressure and oxybutin 2.5mg one three times a day for sweats. My life is so much better now but how long can I take zero dollars sp for

Willy