Hi Storm,
Researchers have found it's best to take statin medications at night because synthesis/formation of cholesterol tends to be highest when your intake of cholesterol is lowest. In one study, individuals that took statins in the morning versus evening had higher cholesterol levels. So, it's not recommended to take statins at night because it'll make you sleepy, but because it's more effective at lowering your cholesterol.
All the best,
Lisa Nelson RD
How to Lower Cholesterol in 8 Simple Steps