Friday, July 13, 2007

Treating Neuropathic Pain without Cognitive Deficit: A Trial and Error Evaluation of Drugs

Disclaimer: Drugs are not the only way to manage pain. Exercise, relaxation techniques, as well as behavioral and phychological links, should all be explored. For serious cases of pain such as spinal cord injury, however, medicine is an invaluable tool to improve quality of life.

Central Neuropathic Pain: The Problem
Treating neuropathic pain is a challenging problem. Reducing pain without creating an imbicile zombie is even more challenging. There are number of aspects that make treatment difficult:

  • "Pain" is a complex and unique target: Spinal cord injury/disease, for instance causes more than just a classic "funny bone" shooting pain sensation. There can be increased muscle tone (spacticity), burning, vibrating, throbbing, or stabbing sensations, and so on. In a case like Chiari Malformation or Arachnoiditis, there can be transient, local, increased intracranial or subarachnoid pressure. That is, your head or neck can be throbbing, and neural tissues *are* being impacted.

  • Everybody responds to drugs differently.
  • As an oversimplification, your biochemistry is as unique as your fingerprints. A drug which relieves pain for one person's may only make another sick.

  • Different people have different requirements. Some people would be happy to trade some short-term memory or alertness for pain relief. Others may have careers with little room for such concessions.

  • Many pain medications affect reasoning, memory, mood, motivation, and energy level.

  • Pain is subjective. This is obvious, but the fact that it is our perception of pain, and not just its cause (pathogenesis) that we wish to treat, makes the process more complicated. (If don't feel a pinch, did it happen?)



Requirements For Finding Helpful Medicines
Because of the variability in treating each case of "pain", finding drugs which help is largely a trial-and-error process. Finding a medicine which helps improve perception of pain thus requires:

  • Knowing which drugs to try.You can't try every drug known to man, you must narrow your search.

  • Trying until something helps. A helpful medicine is one which causes relief from pain while having tolerable side-effects.


My Personal Requirements
My pain management goals are, most important first:
  • Improve cognition.My pain, untreated, greatly diminishes my ability to be productive at my highly-cerebral job. Try completing a long division math problem while someone slowly stabs you and you'll know what I mean. Research has shown that chronic pain causes cognitive problems ([1], [2]). In fact, chronic pain actually causes your brain to shrink over time.

  • Reduce my level of suffering, or perceived pain.


Basically, I want to reduce suffering without causing cognitive issues. This is a balancing act, as reduction of pain definately helps my concentration and reasoning, but many medicines make me tired, foggy, or affect my memory.

What Worked or Didn't Work for Me?
Stay tuned for my next post, where I'll present a history of which medicines I've tried, and how they worked for me. Some made me sleep all day. Others kept me awake all night. Some made me violently ill (barf-o-rama).

Read part two.

MRIs: That will be $3000 plus $10 if you want to see it.

A quick rant about a pet-peeve of mine. Last year I spent thousands on MRIs. I never received a CD or a personal copy of the images. This year I plan on seeing a new neurosurgeon. All the neurosurgeons I've seen so far request that you "hand carry all films". This is because they don't want the hassle of handling your records when they'll probably only see you once.

When I just faxed in a request for a CD containing my latest MRI images, the records staff insisted on charging me $10 to get a "personal copy" of my images. It is not that I cannot afford the ten dollars. I just feel insulted that they provide records free of charge to other physicians, but must charge me even for the first copy I receive.

I told them to ask their neurosurgeons why they require their patients to hand-carry films. Then, I said, feel free to bill my insurance.