The risk or severity of adverse effects can be increased when Olanzapine is combined with Pethidine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Chloroprocaine. Olanzapine may decrease the stimulatory activities of 2,5-Dimethoxy-4-ethylamphetamine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Topiramate. The serum concentration of Thioridazine can be increased when it is combined with Olanzapine. Olanzapine may increase the QTc-prolonging activities of Ondansetron. The risk or severity of adverse effects can be increased when Olanzapine is combined with Tandospirone. The risk or severity of adverse effects can be increased when Thiethylperazine 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 Olopatadine. The therapeutic efficacy of Vildagliptin can be decreased when used in combination with Olanzapine. Olanzapine may increase the sedative activities of Rotigotine. Olanzapine may increase the QTc-prolonging activities of Ziprasidone. Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Paraldehyde. The risk or severity of adverse effects can be increased when Olanzapine is combined with Deramciclane. The risk or severity of adverse effects can be increased when Olanzapine is combined with Diphenoxylate. The therapeutic efficacy of Acarbose can be decreased when used in combination with Olanzapine. Duloxetine may increase the serotonergic activities of Olanzapine. The metabolism of Olanzapine can be decreased when combined with Clotrimazole. The risk or severity of adverse effects can be increased when Olanzapine is combined with Phenobarbital. Milnacipran may increase the serotonergic activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ethyl carbamate. The metabolism of Olanzapine can be decreased when combined with Cholecalciferol. The risk or severity of adverse effects can be increased when Olanzapine is combined with Melperone. The risk or severity of adverse effects can be increased when Bromazepam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Clidinium. Pargyline may increase the serotonergic activities of Olanzapine. The serum concentration of Cilostazol can be increased when it is combined with Olanzapine. 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 Methsuximide. The risk or severity of adverse effects can be increased when Triazolam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Methaqualone. The therapeutic efficacy of Glibornuride can be decreased when used in combination with Olanzapine. The serum concentration of Metoprolol can be increased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when SJG-136 is combined with Olanzapine. Olanzapine can cause a decrease in the absorption of Ferric Carboxymaltose resulting in a reduced serum concentration and potentially a decrease in efficacy. The risk or severity of adverse effects can be increased when Flumazenil is combined with Olanzapine. Etoperidone may increase the serotonergic activities of Olanzapine. Mifepristone may increase the QTc-prolonging activities of Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dihydrocodeine. Olanzapine may increase the QTc-prolonging activities of Fluoxetine. Olanzapine may decrease the stimulatory activities of Hydroxyamphetamine. The risk or severity of adverse effects can be increased when Pergolide is combined with Olanzapine. The risk or severity of adverse effects can be increased when Moricizine is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Agomelatine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Alphaprodine. The serum concentration of Saquinavir can be increased when it is combined with Olanzapine. The serum concentration of Tolvaptan can be increased when it is combined with Olanzapine. Olanzapine may increase the QTc-prolonging activities of Erythromycin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Protriptyline. Olanzapine may increase the QTc-prolonging activities of Eliglustat. The risk or severity of adverse effects can be increased when Olanzapine is combined with Risperidone. Olanzapine may decrease the stimulatory activities of Dextroamphetamine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Clonidine. Olanzapine may increase the QTc-prolonging activities of Lenvatinib. The risk or severity of adverse effects can be increased when Olanzapine is combined with Zonisamide. The serum concentration of Ketoconazole can be decreased when it is combined with Olanzapine. Olanzapine may increase the QTc-prolonging activities of Ibutilide. The risk or severity of adverse effects can be increased when Eletriptan is combined with Olanzapine. Olanzapine may increase the arrhythmogenic activities of Mequitazine. 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 Loxapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Thiopental. The therapeutic efficacy of Empagliflozin can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Fospropofol. The risk or severity of adverse effects can be increased when Olanzapine is combined with Methoxyflurane. The risk or severity of adverse effects can be increased when Olanzapine is combined with Dyclonine. 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 Tedizolid Phosphate is combined with Olanzapine. Benmoxin may increase the serotonergic activities of Olanzapine. The serum concentration of Ibrutinib can be increased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Guanfacine. The risk or severity of adverse effects can be increased when Rufinamide is combined with Olanzapine. Buspirone may increase the serotonergic activities of Olanzapine. Olanzapine may increase the QTc-prolonging activities of Haloperidol. The metabolism of Olanzapine can be decreased when combined with Clomipramine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Procaine. The therapeutic efficacy of Quinagolide can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Piritramide. The metabolism of Olanzapine can be decreased when combined with Diphenhydramine. Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Suvorexant. The risk or severity of adverse effects can be increased when Prazepam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Halothane. Olanzapine may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine. The risk or severity of adverse effects can be increased when Lorazepam is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ziconotide. Lithium may increase the neurotoxic activities of Olanzapine. The risk or severity of adverse effects can be increased when Phenelzine is combined with Olanzapine. The therapeutic efficacy of Piribedil can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Butorphanol. The risk or severity of adverse effects can be increased when Olanzapine is combined with Desloratadine. The metabolism of Olanzapine can be decreased when combined with Theophylline. The serum concentration of Dabrafenib can be decreased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with clomethiazole. The risk or severity of adverse effects can be increased when Olanzapine is combined with DPDPE. The therapeutic efficacy of Levodopa can be decreased when used in combination with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Sevoflurane. 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 Ketobemidone. The risk or severity of adverse effects can be increased when Olanzapine is combined with Levocetirizine. Olanzapine may increase the QTc-prolonging activities of Methadone. The risk or severity of adverse effects can be increased when Olanzapine is combined with Nalbuphine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Cyproheptadine. The serum concentration of Pitavastatin can be increased when it is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Carisoprodol. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ketamine. The risk or severity of adverse effects can be increased when CE-326597 is combined with Olanzapine. The risk or severity of adverse effects can be increased when Olanzapine is combined with Propoxycaine. Olanzapine may increase the QTc-prolonging activities of Leuprolide. The risk or severity of adverse effects can be increased when Olanzapine is combined with Norflurane. Lamotrigine may increase the sedative activities of Olanzapine. Olanzapine may decrease the stimulatory activities of Pseudoephedrine. Olanzapine may increase the antipsychotic activities of Amisulpride. The risk or severity of adverse effects can be increased when Olanzapine is combined with Levetiracetam. The risk or severity of adverse effects can be increased when Olanzapine is combined with Pizotifen. The serum concentration of Olanzapine can be increased when it is combined with Cobicistat. Olanzapine may increase the QTc-prolonging activities of Sulfisoxazole. The therapeutic efficacy of Insulin Aspart can be decreased when used in combination with Olanzapine. Safrazine may increase the serotonergic activities of Olanzapine. Olanzapine can cause a decrease in the absorption of Pazopanib resulting in a reduced serum concentration and potentially a decrease in efficacy. The risk or severity of adverse effects can be increased when Rasagiline is combined with Olanzapine. The therapeutic efficacy of Olanzapine can be increased when used in combination with Pregabalin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Ethosuximide. The risk or severity of adverse effects can be increased when Olanzapine is combined with Raclopride. The metabolism of Tacrolimus can be decreased when combined with Olanzapine. 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 Atorvastatin. The risk or severity of adverse effects can be increased when Olanzapine is combined with Oxybuprocaine. The risk or severity of adverse effects can be increased when Estazolam is combined with Olanzapine. The therapeutic efficacy of Buformin can be decreased when used in combination with Olanzapine.