Certain antidepressants and anti-seizure drugs are among medications that effectively treat diabetic nerve pain, according to a study published in the journal Neurology.
“Providing pain relief for neuropathy is crucial to managing this complicated disease,” said Julie Waldfogel, PharmD, Johns Hopkins Hospital, Baltimore, Maryland. “Unfortunately, more research is still needed, as the current treatments have substantial risk of side effects, and few studies have been done on the long-term effects of these drugs.”
For the systematic review, done by the Agency for Healthcare Research and Quality (AHRQ), researchers looked for studies and other systematic reviews conducted after the American Academy of Neurology’s (AAN) 2011 guideline “Treatment of Painful Diabetic Neuropathy.” A total of 106 studies were included in the review.
The researchers found moderate evidence that the antidepressants duloxetine and venlaxine were effective in reducing neuropathy-related pain.
They also found weak evidence that botulinum toxin, the anti-seizure drugs pregabalin and oxcarbazepine, as well as drugs classified as tricyclic antidepressants and atypical opioids were probably effective in reducing pain.
Waldfogel noted that the long-term use of opioids is not recommended for chronic pain due to lack of evidence of long-term benefit and the risk of abuse, misuse, and overdose.
The researchers noted that while pregabalin works in the same way as gabapentin — both are often used interchangeably in clinical care — this review found gabapentin was not more effective than placebo. This is contrary to the 2011 AAN guideline, which found gabapentin to be probably effective.
The seizure drug valproate and capsaicin cream, which were considered probably effective in the 2011 AAN guideline, were ineffective in this meta-analysis.
“We hope our findings are helpful to doctors and people with diabetes who are searching for the most effective way to control pain from neuropathy,” said Waldfogel. “Unfortunately, there was not enough evidence available to determine if these treatments had an impact on quality of life. Future studies are needed to assess this.”
There were other limitations. One was that all studies were short-term, less than 6 months, and all studies on effective drugs had more than 9% of participants drop out due to adverse effects. Longer-term outcomes should be evaluated in future studies so that side effects and continued effectiveness of the drugs can be assessed.