Promethazine

96 interactions 6 explained in plain English
Also sold as: Phenadoz Phenergan Promethegan
Dr. Brian Staiger, PharmD, BCPS
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: Butorphanol Nasal Spray Amitriptyline Alfuzosin Felbamate Butorphanol Injection Diphenhydramine Topical
94 Major 2 Moderate
All (96) Major (94) Moderate (2)

Major

Promethazine Midazolam Nasal Spray Nayzilam Increased risk of hypoventilation, airway obstruction, desaturation, or apnea Details Promethazine Midazolam Injection Nayzilam Increased risk of hypoventilation, airway obstruction, desaturation, or apnea Details Promethazine Morphine Injection Astramorph® PF Increased risk of urinary retention, severe constipation, and paralytic ileus and an increased risk of profound sedation, respirat... Details Promethazine Moxifloxacin Avelox Increased risk of QT interval prolongation Details Promethazine Moxifloxacin Injection Avelox Increased risk of QT interval prolongation Details Promethazine Moxifloxacin Ophthalmic Moxeza® Increased risk of QT interval prolongation Details Promethazine Nalbuphine Injection Nubain® Increased risk of respiratory and CNS depression; increased risk of paralytic ileus Details Promethazine Octreotide Bynfezia An increased risk of QT prolongation Details Promethazine Octreotide Injection Bynfezia An increased risk of QT prolongation Details Promethazine Ofloxacin Floxin® An increased risk of QT interval prolongation Details Promethazine Ofloxacin Ophthalmic Ocuflox An increased risk of QT interval prolongation Details Promethazine Ofloxacin Otic Floxin® Otic An increased risk of QT interval prolongation Details Promethazine Olodaterol Oral Inhalation Striverdi An increased risk of QT interval prolongation and an increased risk of ventricular arrhythmias Details Promethazine Oxaliplatin Injection Eloxatin® Increased risk of QT-interval prolongation Details

Check another drug

Still have questions about this combination?

Every question gets a real answer from a licensed pharmacist — free, and usually within a day.

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