Lamotrigine with Acetaminophen Interaction Details
Brand Names Associated with Lamotrigine
- Lamictal®
- Lamictal® CD
- Lamictal® ODT
- Lamictal® XR
- Lamotrigine
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Feb 25, 2024
Interaction Effect
Decreased lamotrigine effectiveness
Interaction Summary
In a randomized study, the effect of acetaminophen on the pharmacokinetics of lamotrigine was evaluated. When given concurrently, the half-life and area under the plasma concentration-time curve of lamotrigine decreased by 15% and 20% respectively. Renal clearance for lamotrigine increased by 7%[1].
Severity
Minor
Onset
Delayed
Evidence
Theoretical
How To Manage Interaction
Monitor the clinical effectiveness of lamotrigine therapy. Routine increases in lamotrigine dosage are not necessary, unless therapeutic failure occurs. An occasional dose of acetaminophen is unlikely to significantly decrease lamotrigine concentrations.
Mechanism Of Interaction
Increased renal clearance
Literature Reports
A) Acetaminophen enhances the urinary elimination of lamotrigine after single doses of the anticonvulsant. In healthy volunteers, administration of a single 300 mg dose of lamotrigine followed by acetaminophen 900 mg 3 times a day resulted in a decrease in AUC and serum half-life of 20% and 15%, respectively, compared to administration of lamotrigine with placebo. No differences in peak plasma concentration or time to peak were observed. The percentage of lamotrigine recovered in the urine was also higher when administered with acetaminophen. It was suggested that acetaminophen may enhance removal of lamotrigine from the circulation [1].
References
1 ) Depot M, Powell JR, & Messenheimer JA: Kinetic effects of multiple oral doses of acetaminophen on a single oral dose of lamotrigine. Clin Pharmacol Ther 1990; 48:346-355.
Lamotrigine Overview
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Lamotrigine extended-release (long-acting) tablets are used with other medications to treat certain types of seizures in patients who have epilepsy. All types of lamotrigine tablets (tablets, orally disintegrating tablets, and chewable tablets) other than the extended-release tablets are used alone or with other medications to treat seizures in people who have epilepsy or Lennox-Gastaut syndrome (a disorder that causes seizures and often causes developmental delays). All types of lamotrigine tablets other than the extended-release tablets are also used to increase the time between episodes of depression, mania (frenzied or abnormally excited mood), and other abnormal moods in patients with bipolar I disorder (manic-depressive disorder; a disease that causes episodes of depression, episodes of mania, and other abnormal moods). Lamotrigine has not been shown to be effective when people experience the actual episodes of depression or mania, so other medications must be used to help people recover from these episodes. Lamotrigine is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in the brain.
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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.