I'd like to help, but you haven't said where your neuropathic pain is. If it is in the sciatic nerve I can empathise, because I am going through a similar agony. I've had sciatic nerve pain in my left leg for 6 years or so now. Of the drugs I take for pain, only lorazepam has any effect on it. But when it is working at it's best it takes it away completely. Unfortunately it is not intended for long term use. You become used to it, and a higher dose is needed to give the same effect - in other words it is addictive. I'm taking three 1mg tablets a day, and I have to leave them off now and then when they stop working. I've tried diazapam as well, but I find lorazepam works better.
I also take one 50mg tablet of amitryptiline at night. This is an anti-depressant, but can be used as a sedative for neuropathic pain.
My paracetamol and tramadol, which I take in combination, don't touch it - this, I think, is widely observed to be true of many people by the medical profession, but I suppose it may not be true of everyone.
I was hospitalised just before Christmas with acute sciatic nerve pain in my right side, and was prescribed gabapentin for the first time. I was given 100mg three times a day to start with, which was increased to 600mg by my local doctor after Christmas. After three or four weeks with no improvement, it was raised to 900mg, then 1200mg, in four doses of 300 - still no improvement. I am currently taking 1600mg, and have been advised to spread the doses more evenly over 24 hours, rather than squeeze them into 12 hours with a 12 hour overnight gap in between.
What is CVS therapeutic menthol gel? If that works, I'd like to try it.
I hope this is of some help. I'd be interested to hear how you're getting on.