HBO2 therapy can reduce neuropathic pain

Chronic pain affects about 76 million people in the U.S. and carries an economic burden of nearly $100 billion annually. The most frequently used medications, narcotic and non-narcotic analgesic drugs (e.g., morphine, ibuprofen, etc.), do not provide complete or sustained relief of chronic pain. Scientists are currently seeking alternative solutions for chronic pain management.

One possible solution is hyperbaric oxygen (HBO2) therapy, which is the clinical application of pure oxygen at higher-than-atmospheric pressure for limited time periods to achieve beneficial results. The FDA has approved HBO2 treatment for certain conditions such as decompression sickness (the 'bends') and carbon monoxide poisoning but not for pain specifically.

Yangmiao Zhang, a graduate student in the laboratory of Raymond M. Quock, Ph.D., Professor of Pharmaceutical Sciences at Washington State University, evaluated whether relief of neuropathic pain could be enhanced by increasing the number of HBO2 treatments. Male rats were injected and tested on their paws for pain thresholds at four different times. Twenty-four hours after the last injection, rats were treated with a 60-minute period of room air (the control), or HBO2. Rats that underwent the most number of HBO2 treatments (four 60-minute treatments) recovered approximately 7 days earlier than rats who received a single treatment.

Quock concluded, "While most other HBO2 pain studies focus on inflammatory mechanisms, we believe that HBO2 also reduces pain by acting in the brain. Studying the mechanism of how HBO2 can reduce neuropathic pain can reveal molecular targets in the brain and possibly stimulate the development of new drugs that act on the same targets for long-term relief of chronic pain." This research was supported by Washington State University.