Nortriptyline with Enflurane Interaction Details
Brand Names Associated with Nortriptyline
- Aventyl®
- Nortriptyline
- Pamelor®
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Dec 03, 2023
Interaction Effect
An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) and an increased risk of seizure activity
Interaction Summary
Enflurane may prolong the QT interval in some patients. Because tricyclic antidepressants may also prolong the QT interval and increase the risk of arrhythmias, the concurrent administration of enflurane and tricyclic antidepressants is not recommended . Concomitant administration of amitriptyline and enflurane anesthesia has been reported to result in seizures in two cases .
Severity
Major
Onset
Unspecified
Evidence
Probable
How To Manage Interaction
Avoid concurrent use of enflurane and tricyclic antidepressants, particularly in patients with a history of seizure activity or when hyperventilation or high concentrations of enflurane will be required.
Mechanism Of Interaction
Additive effects on QT prolongation
Literature Reports
A) Two case reports of patients on amitriptyline therapy who experienced seizure activity while receiving enflurane anesthesia have been documented . The first patient, a 42-year old female, was taking amitriptyline 100 mg daily. Anesthesia was induced with fentanyl, enflurane, and nitrous oxide. Approximately three hours after anesthesia was induced, clonic movements of the patient's right hand and forearm were noted. Enflurane concentration was 1% at the time. Changes in ventilation did not affect the involuntary movements, so enflurane was discontinued and replaced with halothane 1%. The movements decreased in frequency and amplitude and subsequently disappeared in approximately one minute. The second case report involved a 39-year old male who was taking amitriptyline 150 mg daily. Anesthesia was maintained with enflurane 1% to 2%, and intermittent clonic movements started in the right arm and leg approximately one hour into the surgery. Enflurane was discontinued and halothane was instituted, which caused the involuntary movements to disappear in approximately two minutes. No further movements were seen during the remaining three hours of anesthesia.
Nortriptyline Overview
-
Nortriptyline is used to treat depression. Nortriptyline is in a group of medications called tricyclic antidepressants. It works by increasing the amounts of certain natural substances in the brain that are needed to maintain mental balance.
Return To Our Drug Interaction Homepage
Feedback, Question Or Comment About This Information?
Ask Dr. Brian Staiger, PharmD, our medical editor, directly! He's always more than happy to assist.
Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.