NeurAxis (NRXS) shares were up sharply premarket Tuesday after the company said the US Food and Drug Administration granted clearance to expand the use of its IB-Stim device for treating functional abdominal pain linked to functional dyspepsia and nausea in patients aged 8 to 21.

The approval is the first FDA-cleared treatment for pediatric functional dyspepsia and builds on the device's prior clearance for irritable bowel syndrome, the company said.

NeurAxis said the expanded use nearly doubles IB-Stim's addressable market and will be launched using its existing reimbursement and provider network.

IB-Stim is a non-surgical device that uses neuromodulation to treat gut-brain interaction disorders, with no FDA-approved drug therapies currently available for these conditions in children, NeurAxis said.