<prompt> Which of the following drugs is both effective and safe to use in a pregnant patient suffering from bipolar disorder?CarbarnazepineLithiumOlanzapineValproic acid  <response>: Ref: KDT 62 p429, 430 All of these drugs can be used for the treatment of bipolar disorder but carbamazepine, lithium and valproic acid are teratogenic. Olanzapine is safe in pregnancy. 