Question: My husband lost both of his legs due to poor circulation. Since the double amputation, he's suffered with phantom leg pain. The pain pills don't help much. Is there anything else you can suggest? - N.R., Eau Claire, Wis.
Answer: Phantom limb pain, where pain is experienced in a limb as if it were still intact, is not entirely understood, but probably occurs as a result of several factors: 1) the sensory nerve pathway just above the point of amputation is intact, causing a firing of sensory nerve impulses representing the entire limb to the brain; 2) the damaged nerves that were cut during amputation are hypersensitive such that a little bit of sensory nerve stimulation at the amputation point causes a whole lot of pain; 3) limbs normally generate counter-regulatory nerve signals to reduce the strength of a touch or temperature impulse, but that's lost with amputation; and 4) the brain creates memories of a painful sensation and cause the pain to persist. By the way, this same phantom pain can be seen following a mastectomy or a tooth extraction.
Treatment of phantom limb pain is not easy. Since abrasion or excess pressure of the stump can trigger or aggravate phantom pain, a comfortable well-padded covering is very important.
Pain medications, especially the codeine, hydrocodone or oxycodone types, are much more effective in treating nerve pain than aspirin, Advil or Tylenol. Another method of treating nerve pain is actually the use of anti-seizure medications such as Tegretol or Neurontin - regardless of whether there's a seizure disorder.
Anti-depressants such as Elavil, Pamelor, Trazodone or Cymbalta can also help chronic phantom pain - regardless of whether or not depression is present. These treatments affect the processing of sensory pain information received by the brain. Hypnosis has also been helpful to amputees.
While not helpful to your husband, there's evidence the chances of developing phantom pain can be reduced by the use of lots of regional anesthesia at the amputation site prior to, during and for a few days after surgery.
Question: What is your opinion of the pain reliever DMSO? I know it's used on horses to relieve tendinitis and arthritis. I've heard it helps with sprains and arthritis in people, but I'm not sure how safe that practice is. - R.H., Roswell, Ga.
Answer: DMSO is a sulfur-based topical ointment or gel suspension that has an amazing ability to be absorbed through the skin and quickly combine with water-based tissues and provide rapid pain relief. DMSO also has the ability to draw water out of inflamed tissues and quickly reduce localized swelling. It's most effective on soft tissue injuries such as muscle or tendon strain because they're plump with water. It's been safely used for more than 50 years to provide pain relief to horses and other animals. Other than causing garlic-like taste and breath and a pungent garlic-like body odor from its sulfur base, it's time-tested safe pain relief for animals and humans not allergic to sulfa or sulfur compounds. It doesn't have any issues with liver toxicity, kidney toxicity or gastrointestinal ulcers and bleeds - unlike traditional anti-inflammatory medications such as aspirin, Advil and Aleve.
DMSO is available in many health food stores and veterinary supply stores as an over-the-counter topical product, but does not have an FDA approval for topical pain relief in humans. The reason for that is unclear, although it is not because of safety concerns. It is FDA-approved for use as a pain reliever instilled in the bladder of folks with "interstitial cystitis." The most likely reason why it's not FDA approved and promoted for humans is economics: there's little point in a drug manufacturer spending millions of dollars seeking formal approval for a drug already widely available without a prescription.
Dr. Mitchell Hecht is a physician specializing in internal medicine. Send questions to him at: "Ask Dr. H," P.O. Box 767787, Atlanta, Ga. 30076.
