A very common side-effect of Quetiapine is drowsiness, so I would recommend you take your dose in the evening. Try to also take Quetiapine close to the time you normally go to sleep - my Quetiapine doubles up as a sleeping medication for me, kinda like a 2 in 1

You're starting off on a moderately high dosage. In most cases, Quetiapine is started at a rather quite low dosage (around 50mg) and slowly increased up to the required dosage, which can help lower the severity of the side effects. So I'd expect you may feel rather sleepy and drowsy. I've been on 600mg Quetiapine for 1 year and down to 300mg for two years and I still feel drowsy when I take it!

Don't worry, though: the severity of the drowsiness eventually decreases and becomes a lot more bearable over time. Try not take the Quetiapine after 1am at night, either. If you take it too late, you may still feel drowsy in the morning

RB