Shares of Sucampo Pharmaceuticals soared 24% as the company received an expanded indication for Amitiza, which is now the only FDA-approved oral medication for constipation from taking opioid painkillers for non-cancer pain. 

In this video, health-care analyst David Williamson explains what this means for Sucampo and why, despite the size of the market, investors may not want to rush in and grab shares after today's big pop.