I think drugs typically start failing after a while, because the body gets used to them, and adjusts things so the feeling ability is restored.

For example, in the brain, it has been recently discovered that in people taking opiates for pain, over time, the body, creates MORE receptors, so the drug level has to be increased. This happens in the glial support cells, which detect that pain signals are impaired, or blocked, and the glial cells send out a chemical that induces the neurons to make more receptors. This is the basis for one form of "tolerance".

Biological tolerance appears to be the way the body will continue to provide a framework for sensory transmission.

You know when I first started taking neurontin I felt like it was helping and then for a long period did not. I wonder if it was just that I was having a better time pain wise but not so much from the med.
I heard that when I was at Cleveland Clinic pain program about opiates and the brain receptors.

I aqm familiar with the development of more receptors, just didn't think it would happen so fast. I have taken opiates for bladder pain for over 10 years and still can take the same dose to get the same relief. Lyrica and Gaba seem to wear off sooooo much faster.

lyrica and fentanyl
 

I have been taking a combination of Lyrica (300mg per day) and a fentanyl patch (75 mcg) for about 10 months and can say that I have almost no pain at all. It may seem like a lot of medicine, but I tolerate it very well. I was diagnosed with neuropathy three years ago, and in the beginning had all of the symptoms...terrible burning, shooting pains, numbness from mid calf down. I wasn't able to do anything. With this medicine, I am back to doing most of the things that I did before. My pain level is usually 2-3, although there are times that it goes up to 8-9, usually first thing in the morning. God bless you all...hope this helps!:)

Hi Rose
I took lyrica up to 450 mg once and it did nothing after being super fab up to about 300mg where it eventually lost its effect.

most take a cocktail. Adding elavil 25mg can make a startling difference.
Tramadol is another. Good Luck