Amitriptyline, duloxetine equally effective for treating diabetic neuropathy
MedWire News: The drugs amitriptyline and duloxetine are equally effective for treating painful diabetic neuropathy (PDN), show study results.
Anil Bhansali (Postgraduate Institute of Medical Education and Research, Chandigarh, India) and fellow researchers carried out a randomized, double blind, crossover study including 58 patients with PDN to compare the efficacy of treatment with amitriptyline (10, 20, or 50 mg/day) or duloxetine (20, 40, or 60 mg/day).
The patients were treated with one drug for 6 weeks, followed by a 6-week washout period, before being given the other drug for 6 weeks.
The team found that 55%, 24%, and 15% of the patients had good, moderate, and mild pain relief on amitriptyline, respectively, while 59%, 21%, and 9% had corresponding rates of pain relief on duloxetine.
A total of 111 adverse events occurred among patients on amitriptyline compared with 112 among patients on duloxetine. Dry mouth occurred more frequently with amitriptyline than duloxetine, accounting for 55% versus 24% of all side effects.
When patients were asked which medication they preferred, more chose duloxetine than amitriptyline, at 48% versus 36%. However, this was not statistically significant.
The American Diabetes Association currently recommends amitriptyline, a tricyclic antidepressant, as the first-choice therapy for treating PDN, but doses have to be carefully controlled due to its anticholinergic adverse effects at higher doses.
Duloxetine, a selective serotonin norepinephrine reuptake inhibitor, is also approved for treatment of PDN. It has been shown to not only relieve pain, but also improve functionality and quality of life.
Bhansali and co-authors conclude in the journal Diabetes Care that their findings suggest that the two drugs have comparable efficacy and tolerability for management of PDN.
However, they suggest: "A similar head-to-head comparison in a multicentric clinical trial using a larger sample size could possibly demonstrate the superiority of either drug."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Helen Albert