Clozapine

114 interactions 7 explained in plain English

Also sold as: Clozaril Versacloz

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 4, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Ketoconazole Topical Metoclopramide Nasal Spray Metoclopramide Injection Fentanyl Transdermal Patch Estradiol Peginterferon Alfa-2A Injection

3 Contraindicated 105 Major 6 Moderate

All (114) Contraindicated (3) Major (105) Moderate (6)

Major

Clozapine Levofloxacin Levaquin Increased risk of QT interval prolongation Details Clozapine Levofloxacin Injection Levaquin Increased risk of QT interval prolongation Details Clozapine Levonorgestrel After banger Increased clozapine exposure and increased risk of adverse effects Details Clozapine Levonorgestrel Intrauterine System Kyleena Increased clozapine exposure and increased risk of adverse effects Details Clozapine Lithium Carbonate Lithobid Weakness, dyskinesias, increased extrapyramidal symptoms, encephalopathy, and brain damage Details Clozapine Loperamide Diamode An increased risk of QT interval prolongation, which may increase risk of cardiotoxicity (torsade de pointes, cardiac arrest) Details Clozapine Mefloquine Lariam® Increased risk of QT interval prolongation Details Clozapine Metronidazole Flagyl An increased risk of QT interval prolongation Details Clozapine Metronidazole Injection Flagyl An increased risk of QT interval prolongation Details Clozapine Metronidazole Topical MetroCream® An increased risk of QT interval prolongation Details Clozapine Metronidazole Vaginal MetroGel® Vaginal An increased risk of QT interval prolongation Details Clozapine Mexiletine Mexitil® Increased clozapine exposure Details Clozapine Morphine Injection Astramorph® PF Increased risk of urinary retention, severe constipation, and paralytic ileus and an increased risk of profound sedation, respirat... Details Clozapine Moxifloxacin Avelox Increased risk of QT interval prolongation Details Clozapine Moxifloxacin Injection Avelox Increased risk of QT interval prolongation Details Clozapine Moxifloxacin Ophthalmic Moxeza® Increased risk of QT interval prolongation Details Clozapine Nalbuphine Injection Nubain® Increased risk of respiratory and CNS depression; increased risk of paralytic ileus Details Clozapine Octreotide Bynfezia Increased risk of QT interval prolongation Details Clozapine Octreotide Injection Bynfezia Increased risk of QT interval prolongation Details Clozapine Ofloxacin Floxin® Increased risk of QT interval prolongation Details Clozapine Ofloxacin Ophthalmic Ocuflox Increased risk of QT interval prolongation Details Clozapine Ofloxacin Otic Floxin® Otic Increased risk of QT interval prolongation Details Clozapine Olodaterol Oral Inhalation Striverdi An increased risk of QT interval prolongation and an increased risk of ventricular arrhythmias Details Clozapine Oxaliplatin Injection Eloxatin® Increased risk of QT-interval prolongation Details Clozapine Peginterferon Alfa-2A Injection Pegasys Increased clozapine exposure Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.