Some insurances do not allow 90 day on certain meds. Then there's the pharmacy...CVS allows us 90 days, but Walgreens limits. So we used our local small independently owned pharmacy for 90 days. He just asked husband if he can switch it to 30 days, even tho the doctor allows 90 days. It happens that the pharmacy makes less money on the 90 days. This independent pharmacist loses $200 if he gives my husband a 90 day, instead of (3) 30 days. Told him it was inconvenient, since husband is handicapped. He offered free home delivery, since it's on his way home. Walgreens made the change lately, and have even gone as far as breaking open boxes and repackaging for 30 days supply over 90 days. Not happy with them, but daughter works there and can get an override on that, at least at her location. These are not pain meds or upper tier meds that require ID or watch. These are routine asthma meds.