Can seroquel (quetiapine) cause strange almost hallucinatory thoughts in the daytime...take 100 for sleep (also take tegretol)?

Yes: Any psychiatric medication can potentially cause abnormal thoughts, dreams, neurologic side effects depending on what the medication is being used for and a person's sensitivity to it. Talk to your doctor about this side effect to determine if it needs to be changed or eliminated.

Yes: There can be addictive effect combing both medication causing increase in cns depression. Tegretol is an enzyme inducer which might lower the efficacy of other medication you are taking . If medication are making you too drowsy consider either lowering dose or try other sleep aid.