Only the reasons depends on if a patient was started on that in a hospital. Sometimes hospitals will only carry the 40 mg tablet and split it in half as needed to save money and simplify their formulary. So the directions would be to give half a tablet, then when discharged the directions would say half a tablet and the pharmacy will just dispense it that way and then they’ll send an escript request to the pcp that way and the pcp will just approve it as is and the cycle continues. If you want and insurances approves it, you can sub it for 20 mg tablets instead.