lithium olanzapine and setraline?

[devilhue]

i take lithium at 1000mg olanzapine at 50mg and sertaline have taken the lithium for nearly 1 1/2yrs now..... my doctor didnt say when he put me on olanzapine to do any different............. when my mum went to put up a new prescripton the pharmasist told her i should take the lithium and the olazapine 2hours apart cause they counteract each other and make the lithium stronger..... is this right? why didnt my doctor tell me this?
im uk based.
makes me really thristy and crave sweet things, not putting on weight loosing it.
also about 30min-1hr after taking it i feel like im going under anasthetic.

[tinmuning]

During concomitant use of these drugs, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

[devilhue]

thanks im so confused by all the meds