Among the main treatments for idiopathic neuropathy, nortriptyline and duloxetine outperform pregabalin when pain reduction and adverse effects are considered together, according to a study guided by patient engagement.

There have been no efficacy trials of drugs to treat patients with idiopathic neuropathy — also called cryptogenic sensory polyneuropathy (CSPN) or small fibre sensory peripheral neuropathy — so there is little information to guide drug choices for these patients, the US study authors say.

They sought to identify the best drug for treating CSPN by engaging 402 patients to determine which of these drugs (and a fourth, mexiletine, which is not registered in Australia) were most effective and tolerable.

Patients were initially randomly assigned to one of the four drugs, and assignments were updated every 13 weeks based on the utility of each treatment — using a measure that combined efficacy rates and treatment discontinuation rates into a single value.