Nobody knows why some people get months of relief from nerve blocks, while others get just hours of relief. The most relief I ever got from a nerve block was 3 hours, but that was enough to demonstrate to my doctor that my pain was indeed neuropathic. It was a diagnostic success but a therapeutic failure, just as in your case. For what it's worth, pain killers rarely helped me either, and in the case of narcotics, eventually made my pain worse.

So where does that leave people like us? Neuropathic pain is notoriously difficult to treat, but there are many options available. In your case, it appears as if the car accident set the stage for your pain. This is not unusual, as occipital neuralgia is often caused by trauma to the neck, which is common in such accidents. A more general term for pain due to neck trauma is "cervicogenic pain" (or "cervicogenic headache,") owing to the involvement of the cervical vertebrae and cervical nerves in the neck an lower portion of the head. An MRI may show trauma in this region, but occipital neuralgia often occurs without anything showing up on MRI (or X-Rays, CT scans, etc.) If trauma is evident, a surgeon may be able to help.

However, if MRIs and other imaging studies turn up nothing, this doesn't mean you don't have damage to the nerve or nearby structures; it simply means that the damage is too small to be seen, even though the pain and other symptoms may be severe. In this case, your doctor will need to treat your symptoms under the assumption that you have nerve damage.

Since traditional pain killers are frequently ineffective with nerve pain, your doctor may want to try other drugs shown to reduce nerve pain. Some of these drugs include certain anti-depressants, anti-seizure medications, and neuropathic agents (like the gabapentin you couldn't tolerate). Whether any given drug will help you is not predictable (as of yet,) so trial and error is called for. Be prepared to try several different drugs before finding one that helps with a minimum of bad side-effects. I am currently getting good relief of the stabbing pains on Cymbalta at 60mg/day. I still have contant pain that increases and decreases throughout the day, but it is manageable most of the time.

Best of luck to you!