Montelukast with Gemfibrozil Interaction Details
Brand Names Associated with Montelukast
- Montelukast
- Singulair®
Brand Names Associated with Gemfibrozil
- Gemfibrozil
- Lopid®
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Nov 25, 2023
Interaction Effect
Elevated montelukast plasma concentrations
Interaction Summary
Concurrent administration of montelukast with gemfibrozil, a selective and strong CYP2C8 inhibitor, significantly increased montelukast plasma concentrations, AUC, and t(1/2) in a randomized, placebo-controlled crossover study (n=10). The interaction appears to be the result of decreased systemic clearance of montelukast. During long term montelukast treatment, a 50% to 80% reduced dose of montelukast may be advisable when administered concurrently with gemfibrozil.
Severity
Moderate
Onset
Rapid
Evidence
Established
How To Manage Interaction
Concurrent use of montelukast and gemfibrozil may result in elevated montelukast plasma concentrations as a result of decreased systemic clearance of montelukast. During long term montelukast therapy, use a 50% to 80% reduced dose of montelukast when concurrently administered with gemfibrozil, and monitor for increased montelukast side effects.
Mechanism Of Interaction
Decreased systemic clearance of montelukast
Literature Reports
A) In a randomized, placebo-controlled, two-phase, crossover study (n=10), concurrent therapy with gemfibrozil and montelukast resulted in significantly increased plasma concentrations of montelukast. Healthy volunteers (age range, 20 to 26 yr) received gemfibrozil 600 mg or placebo twice daily for 3 days. On day 3, montelukast 10 mg was given 1 hour after the morning dose of gemfibrozil or placebo. Blood samples were taken periodically for 24 hours following montelukast administration. The mean AUC, Cmax, and t(1/2) of montelukast when administered with gemfibrozil were increased by 4.5 fold (range, 3.2 to 6.6 fold; p less than 0.001), 1.5 fold (range, 1 to 2.2 fold; p less than 0.001), and 3 fold (from 4.5 to 13.5 hour; p less than 0.001), respectively, compared with placebo. In this study, coadministration of gemfibrozil, a selective and strong CYP2C8 inhibitor with montelukast resulted in a 435% increase in AUC compared to placebo, and estimated to be an almost 80% decrease in systemic clearance of montelukast. The authors suggest that during long term montelukast treatment, a 50% to 80% reduced dose of montelukast may be advisable when concurrently administered with gemfibrozil .
Montelukast Overview
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Montelukast is used to prevent wheezing, difficulty breathing, chest tightness, and coughing caused by asthma in adults and children 12 months of age and older. Montelukast is also used to prevent bronchospasm (breathing difficulties) during exercise in adults and children 6 years of age and older. Montelukast is also used to treat the symptoms of seasonal (occurs only at certain times of the year), allergic rhinitis (a condition associated with sneezing and stuffy, runny or itchy nose) in adults and children 2 years of age and older, and perennial (occurs all year round) allergic rhinitis in adults and children 6 months of age and older. Montelukast should be used to treat seasonal or perennial allergic rhinitis only in adults and children who cannot be treated with other medications. Montelukast is in a class of medications called leukotriene receptor antagonists (LTRAs). It works by blocking the action of substances in the body that cause the symptoms of asthma and allergic rhinitis.
Gemfibrozil Overview
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Gemfibrozil is used with diet changes (restriction of cholesterol and fat intake) to reduce the amount of cholesterol and triglycerides (other fatty substances) in the blood in certain people with very high triglycerides who are at risk of pancreatic disease (conditions affecting the pancreas, a gland that produces fluid to break down food and hormones to control blood sugar). Gemfibrozil is also used in people with a combination of low high-density lipoprotein (HDL; 'good cholesterol') levels and high low-density lipoprotein (LDL; 'bad cholesterol') and triglyceride levels to reduce the risk of heart disease. Gemfibrozil is in a class of lipid-regulating medications called fibrates. It works by reducing the production of triglycerides in the liver.
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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.