Nearly 20 companies have been named in lawsuits over decongestants that a U.S. Food and Drug Administration panel found didn’t work at all; some are saying they shouldn’t be sued.

Following a meeting on Sept. 11 and Sept. 12, an FDA committee found oral decongestants containing phenylephrine, purchased over the counter for colds and flus, were not effective. About 30 class actions followed, most naming the Procter & Gamble Co. and Johnson & Johnson. But dozens of other companies with big names have been sued, many of which sell store brand decongestants, such as Walgreens, Walmart, Target, CVS and Rite Aid.