I can shed some light on this a little and answer some of these questions. I have atypical trigeminal neuralgia that happened after some odd dental work. The nerve in my face was damaged. The pain was horrendous.

I use a compounded cream with Gabapentin, lidocaine and capsaicin and rub it on the affected area four to five times a day.

I felt dizzy the first two days I used it.

I got little relief the first week or two. Then, suddenly, the third week, I felt an improvement.

My face does not feel particularly numb. When I use it 5x (as opposed to 4) sometimes I feel a little numbing in my face.

It mostly just weakens that gawd awful pain from hexx.

In my case the cream simply influences the pain site directly.

It has been a huge blessing.

If I forget to use it, I absolutely feel the pain coming back clearly. A cold wind does cause more pain.

I don't seem to have side effects...perhaps a tiny amount of weight gain and some additional memory issues. But minor (in comparison to my other meds). My neuro prescribed this largely because I was having great stomach difficulties with the meds he had prescribed for me previous to this tx. Other than perhaps the first two days, this compounded cream does not bother my stomach. It is a life saver!!!!

Hope your situation works out very well and brings much relief.