When given both an anti-seizure drug (gabapentin) and an antidepressant (nortriptyline), patients suffering from neuropathic pain caused by nerve damage or disease experienced less pain than when they took one or the other individually, reports Dr. Ian Gilron.
"It was also exciting to discover the effect of this combination on sleep interference," added Gilron.
He pointed out that people rated sleep interference with the combined drugs as 1.0 on a scale of 10, compared to 2.2 when they took each drug individually.
"That's a very important issue for this group of patients, whose debilitating, unrelenting pain often interferes with normal sleep," he said.
This is the first time that the researchers have found a drug combination that also helps patients sleep better.
Gilron says that it is important to understand how drugs interact, since 45 per cent of Canadians being treated for neuropathic pain take two or more pain drugs.
There may also be safety issues.
"We need more evidence from carefully conducted trials in support of each particular combination, and let the doctors and patients know about such results," said Gilron.
The methodology behind the treatment could also be applied to the study of other chronic conditions such as cancer-related pain, spinal disk disease, and the pain experienced after chemotherapy and mastectomies, said Gilron.
The study's findings have been published in The Lancet.