I don't no much about any of this and probably sound like an amateur when I say this but... I've got this severe pain from l1 -s1 and the only thing that takes the edge of it is an anti-inflamatory which is meloxicam 15mg and tylenol 3 with codeine x 2. This is the only combo that seems to improve things and the doc doesn't mind doling these out to me so maybe their quite common and you've tried them already.

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