Do you know what is causing the pain, and are you also taking pain killers and anti-inflammatories such as ibuprofen, or have you been prescribed diclofenac / voltarol? There are rubs such as ibuleve and voltarol gel that contain tiny amounts of the anti-inflammatory drug but I'm unsure whether it is the rubbing or the gel that gives the relief. Have you tried a budget pack of frozen peas, wrapped in a Tshirt and applied to the pain?
On a completely different tack, I have found my back pain relieved recently by using diuretic tablets, so depending on your own condition that might be an additional option.