Just so we're clear, GABA and gabapentin are not the same thing. Gabapentin requires a prescription, but GABA does not; it is sold as a supplement.

GABA

Gabapentin

Personally, I would not have/permit a lumbar puncture/spinal tap without absolute necessity. I would want to know why the doctor wants it, what s/he will learn from it, and whether there aren't any alternatives.

Same with nerve biopsy; it depends on your symptoms and what s/he's looking for. In my case, I asked my neuro(s) if they wanted a nerve biopsy, and they all said it wasn't necessary because of my symptoms; yours may be quite different.

Doc

It is gabapentin. I couldn't remember the name.i am not sure about the spinal tap. It sounds more exploratory, as in looking to rule out causes of my neuropathy. I haven't signed up for any of the 3 yet. I go back in February to discuss more. Alcohol, diabetic, chemo induced, and HIV neuropathy have all been ruled out. My feet are numb, legs up to calves are partially numb, my hands are affected, my heart, bladder, and bowels are affected, no reflexes, never had any that I can remember. Burning pains in legs on occasions, cramps, and my feet and toes will get stuck in weird positions.

Hi Dr. Smith
I did have a spinal tap due to my symptoms they were looking to diagnose MS. That is one of the test that they can do that with.
I also had a nerve biopsy. I was lucky they only did the hole punch biopsy. It was not bad at all. However, with both you always do run the risk of infection following the procedure.
hopeful