D-cycloserine is an antibiotic which is used in the treatment of tuberculosis. It is sold by Eli Lilly under the brand name Seromycin. Apart from its antiboitic activity, the drug also has effects in the brain, and has been found to be effective in helping people to overcome phobias, and to help children with autism to improve their social and communication skills.
A recent study in rats with neuropathic pain has shown that after taking D-cycloserine daily for two weeks, they were substantially less sensitive to touch in the painful areas. The greater the dose, the greater the reduction in sensitivity. The drug did not appear to affect the normal pain sensations in areas of the body without neuropathic pain.
Although it's painkilling properties have so far only been tested in rats, three features of this drug are particularly encouraging:
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