The therapeutic efficacy of Ciglitazone can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Flibanserin. The risk or severity of adverse effects can be increased when Pentobarbital is combined with Olanzapine. Caroxazone may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Barbital. Olanzapine may increase the arrhythmogenic activities of Mequitazine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Heroin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Loprazolam. The risk or severity of adverse effects can be increased when Olanzapine is combined with Loratadine. The serum concentration of Olanzapine can be decreased when it is combined with Teriflunomide. The serum concentration of Cilostazol can be increased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Baclofen. The risk or severity of adverse effects can be increased when Olanzapine is combined with Sepranolone. The risk or severity of adverse effects can be increased when Olanzapine is combined with Mepivacaine. Octamoxin may increase the serotonergic activities of Olanzapine. The metabolism of Olanzapine can be decreased when combined with Caffeine. The risk or severity of adverse effects can be increased when Flunitrazepam is combined with Olanzapine. Olanzapine may decrease the stimulatory activities of Mephentermine. The metabolism of Olanzapine can be decreased when combined with Tipranavir. Olanzapine may increase the QTc-prolonging activities of Granisetron. The risk or severity of adverse effects can be increased when Olanzapine is combined with Amobarbital. Olanzapine may decrease the stimulatory activities of 3,4-Methylenedioxyamphetamine. Indalpine may increase the serotonergic activities of Olanzapine. The metabolism of Olanzapine can be decreased when combined with Dosulepin. The metabolism of Olanzapine can be decreased when combined with Simeprevir. Olanzapine can cause a decrease in the absorption of Iron Dextran resulting in a reduced serum concentration and potentially a decrease in efficacy. The risk or severity of adverse effects can be increased when Methysergide is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ezogabine. The risk or severity of adverse effects can be increased when Promethazine is combined with Olanzapine. The risk or severity of adverse effects can be increased when CE-326597 is combined with Olanzapine. The metabolism of Olanzapine can be decreased when combined with Lobeglitazone. The risk or severity of adverse effects can be increased when Olanzapine is combined with Gabapentin Enacarbil. The risk or severity of adverse effects can be increased when Olanzapine is combined with Enflurane. Venlafaxine may increase the serotonergic activities of Olanzapine. The serum concentration of Tolvaptan can be increased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when Isocarboxazid is combined with Olanzapine. Mebanazine may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when BL-1020 is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Methadyl Acetate. The metabolism of Olanzapine can be decreased when combined with Mexiletine. Lamotrigine may increase the sedative activities of Olanzapine. Pargyline may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Tolcapone. The therapeutic efficacy of Mesalazine can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Thiamylal. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ethyl loflazepate. The risk or severity of adverse effects can be increased when Olanzapine is combined with Remifentanil. The therapeutic efficacy of Phenformin can be decreased when used in combination with Olanzapine. Perampanel may increase the central nervous system depressant (CNS depressant) activities of Olanzapine. The risk or severity of adverse effects can be increased when Methylene blue is combined with Olanzapine. The therapeutic efficacy of Amantadine can be decreased when used in combination with Olanzapine. The therapeutic efficacy of Metformin can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dihydromorphine. The risk or severity of adverse effects can be increased when Vilazodone is combined with Olanzapine. Olanzapine can cause a decrease in the absorption of Delavirdine resulting in a reduced serum concentration and potentially a decrease in efficacy. The metabolism of Olanzapine can be decreased when combined with Celecoxib. The risk or severity of adverse effects can be increased when Olanzapine is combined with Molindone. The risk or severity of adverse effects can be increased when Olanzapine is combined with Oxethazaine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Trans-2-Phenylcyclopropylamine. The risk or severity of adverse effects can be increased when Codeine is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Pipotiazine. The risk or severity of adverse effects can be increased when Tramadol is combined with Olanzapine. The therapeutic efficacy of Tolbutamide can be decreased when used in combination with Olanzapine. Iproclozide may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Perphenazine is combined with Olanzapine. Olanzapine may increase the QTc-prolonging activities of Lopinavir. The therapeutic efficacy of Saxagliptin can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Morphine is combined with Olanzapine. Olanzapine can cause a decrease in the absorption of Iron resulting in a reduced serum concentration and potentially a decrease in efficacy. The risk or severity of adverse effects can be increased when Delorazepam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Nortriptyline. The metabolism of Olanzapine can be decreased when combined with Paroxetine. Olanzapine may increase the QTc-prolonging activities of Vandetanib. Olanzapine may increase the QTc-prolonging activities of Clarithromycin. Olanzapine may increase the QTc-prolonging activities of Azithromycin. The serum concentration of Cefditoren can be decreased when it is combined with Olanzapine. Minaprine may increase the serotonergic activities of Olanzapine. Doxylamine may increase the central nervous system depressant (CNS depressant) activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Risperidone. Olanzapine can cause a decrease in the absorption of Cefpodoxime resulting in a reduced serum concentration and potentially a decrease in efficacy. Olanzapine may decrease the stimulatory activities of Chlorphentermine. The risk or severity of adverse effects can be increased when Camazepam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Lisuride is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dexmedetomidine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Bromperidol. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dezocine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Meclizine. The risk or severity of adverse effects can be increased when SJG-136 is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ketazolam. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dihydrocodeine. Benmoxin may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Etifoxine. Olanzapine may increase the QTc-prolonging activities of Escitalopram. Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Hydrocodone. Olanzapine may increase the QTc-prolonging activities of Quetiapine. Olanzapine may increase the QTc-prolonging activities of Gadobenic acid. The risk or severity of adverse effects can be increased when Olanzapine is combined with Levocetirizine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Zotepine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Brotizolam. The risk or severity of adverse effects can be increased when Zolmitriptan is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ethotoin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Vigabatrin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Oxprenolol. Olanzapine may decrease the stimulatory activities of MMDA. The risk or severity of adverse effects can be increased when Olanzapine is combined with Triprolidine. Olanzapine may increase the QTc-prolonging activities of Erythromycin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Carisoprodol. Minocycline may increase the central nervous system depressant (CNS depressant) activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Phenobarbital. The risk or severity of adverse effects can be increased when Almotriptan is combined with Olanzapine. Olanzapine can cause a decrease in the absorption of Cefuroxime resulting in a reduced serum concentration and potentially a decrease in efficacy. The therapeutic efficacy of Gusperimus can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ethyl chloride. The therapeutic efficacy of Glyburide can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Amperozide. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dextropropoxyphene. The risk or severity of adverse effects can be increased when Olanzapine is combined with Fentanyl. The serum concentration of Tizanidine can be increased when it is combined with Olanzapine. Pirlindole may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Methylphenobarbital. The risk or severity of adverse effects can be increased when Ergonovine is combined with Olanzapine. Olanzapine can cause an increase in the absorption of Dexmethylphenidate resulting in an increased serum concentration and potentially a worsening of adverse effects. Olanzapine may increase the QTc-prolonging activities of Iloperidone. Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Thalidomide. The risk or severity of adverse effects can be increased when Olanzapine is combined with Sertindole. The risk or severity of adverse effects can be increased when Thioproperazine is combined with Olanzapine. Olanzapine may increase the QTc-prolonging activities of Anagrelide. Olanzapine may decrease the stimulatory activities of Phentermine. Brimonidine may increase the central nervous system depressant (CNS depressant) activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Cyclizine.