Obstructive Sleep Apnea
(OSA) is caused by a physical obstruction,therefore any drug that will further relax throat muscles will increase the severity of OSA.
So marijuana will increase the severity of sleep apnea. Maybe you are thinking of insomnia
, but in addition to the decrease in cognitive function because of the pot, you will be dulled because you are more hypoxic as well. This has come up before, so I'm sure there are lots of folks out there hoping for a medicinal marijuana cure