Any Pain Medication Said Effective When Treating Diabetic Nerve Pain

Prescribers can consider cheaper drugs until further studies are done…

Millions of patients with diabetes take medication to ease the shooting, burning nerve pain that their disease can cause. Recently published research suggests that it does not matter which medicine they take; they will still get relief. This leads patients and prescribers to consider cost, not effectiveness, as a crucial factor in deciding which medicine to choose for diabetic neuropathy or nerve pain.

A study led by Marcio Griebeler, MD was created to evaluate the comparative effectiveness of oral and topical analgesics for diabetic neuropathy via multiple electronic databases between January 2007 and April 2014. A total of 65 randomized controlled trials involving 12,532 patients evaluated 27 pharmacologic interventions, with approximately 50% of these studies having high or unclear risk of bias were assessed.

Nine head-to-head trials showed greater pain reduction associated with serotonin-norepinephrine reuptake inhibitors (SNRIs) than anticonvulsants and with tricyclic antidepressants (TCAs) than topical capsaicin. A network meta-analysis showed that SNRIs, topical capsaicin, and anticonvulsants were better than placebo for short-term pain control. When comparing carbamazepine to duloxetine and amitriptyline, they were more effective than placebo.

This study had a multitude of limitations including a majority of studies evaluated showing high and unclear bias. Most evidence came from indirect comparisons of trials with a short duration of follow-up (<3 months). Lastly, information evaluated was limited collection as not to account for adherence, language barriers, and measurement cross-applicability.

The researchers concluded, "These treatments all work about the same, but what’s different is their side effects and cost. The older medications are an order of magnitude cheaper, about $15-$20 a month, compared to newer ones at nearly $200 per month." Currently, the newer drugs have earned the highest level of recommendation in national treatment guidelines. However, in multiple trials, there is enough evidence to suggest their similar efficacy.

The best way to compare efficacy would be in head-to-head trials of the medications of interest, but until those are completed, it is recommended that prescribers take cost into consideration when treating patients with diabetic peripheral neuropathy.

Practice Pearls:

• Current evidence finds expensive and cheaper drugs both work well. Doctors should consider costs until more studies are done.
• This study is not definitive due to many limitations. However, encouragement of head-to head trials is best way to compare efficacy results.
• It is recommended that prescribers take cost into account when prescribing medications for patients with diabetic peripheral neuropathy.

Griebeler M. et al. "Pharmacologic Interventions for Painful Diabetic Neuropathy: an umbrella systematic review and comparative effectiveness network meta-analysis." Ann Intern Med. 2014;161(9):639-649, 4 Nov. 2014. Web. 15 Nov. 2014.