Is Medication For Kidney Stone Recommended Even If There No Pain?

My husband is 82 years of age and a year ago had an aortic aneurism . He is a veteran and He has a splint. He has a kidney stone now 4mm.We just came from the Veterans hospital he was prescribed Hydrocodone 10mg/ACETAM 325mg TAB today1 tablet 4 times a day for pain. He has not passed this stone yet. Should he take the tablet if he is not in pain.