Understanding What Meds Should Not Be Taken With Montelukast

According to several clinical resources, certain medications, herbal supplements, and even certain foods can negatively interact with montelukast, affecting its efficacy and potentially increasing side effects. Understanding what meds should not be taken with montelukast is crucial for ensuring the medication works effectively and for safeguarding patient health.

Quick Summary

This guide examines specific medications and substances, including certain anticonvulsants, antibiotics, and nonsteroidal anti-inflammatory drugs, that have documented interactions with montelukast. It details how these interactions affect drug levels and efficacy, emphasizes the need for close medical supervision, and highlights other substances to use with caution.

Key Points

• Reduced Efficacy: Certain medications like carbamazepine and rifampin can speed up montelukast's metabolism, reducing its effectiveness.

• Worsened Asthma: Individuals with aspirin-exacerbated respiratory disease (AERD) should avoid NSAIDs like ibuprofen and aspirin to prevent worsened asthma symptoms.

• Increased Drowsiness: First-generation antihistamines such as diphenhydramine can increase drowsiness when taken with montelukast.

• Impact on Other Meds: Montelukast can potentially reduce the effectiveness of warfarin, a blood thinner, requiring careful monitoring by a doctor.

• Herbal and Supplement Interactions: St. John's Wort and cannabis can also interfere with montelukast, altering its efficacy or side effects.

• Consult a Professional: Always inform your doctor or pharmacist about all medications and supplements you are taking to proactively manage interactions.

Montelukast, commonly known by its brand name Singulair, is a vital medication for managing and preventing asthma and treating seasonal allergies. However, its effectiveness and safety can be impacted by other drugs. Medications can interfere with montelukast's metabolism, affecting its concentration in the body and potentially causing adverse effects. Always consult a healthcare provider or pharmacist about all medications, supplements, and herbal products you take to prevent harmful drug interactions.

Medications that Reduce Montelukast's Effectiveness

Some drugs can accelerate the metabolism of montelukast in the liver, which can lower its concentration in the blood and diminish its therapeutic effects. If these medications are necessary, a doctor may need to monitor the patient more closely or adjust dosages.

• Certain Anticonvulsants: This class of drugs, used to treat seizures, are known to increase the activity of liver enzymes that metabolize montelukast. Examples include:

  • Carbamazepine (Tegretol)
  • Phenytoin (Dilantin)
  • Phenobarbital

• Rifampin: This antibiotic, primarily used for tuberculosis, is a potent enzyme inducer and can significantly reduce the levels of montelukast in the body, making it less effective.

• Enzalutamide (Xtandi): This medication used for treating prostate cancer also falls into the category of drugs that can decrease montelukast's efficacy.

Medications that Increase Side Effects or Risks

Combining montelukast with other substances can sometimes amplify side effects or pose other health risks, such as increased drowsiness or potential for liver complications. While some of these are managed with caution rather than complete avoidance, they warrant careful attention.

• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): While many can take NSAIDs and montelukast without issue, individuals with aspirin-exacerbated respiratory disease (AERD) should avoid NSAIDs such as aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve). In these individuals, NSAIDs can trigger or worsen asthma symptoms.

• First-Generation Antihistamines: Medications like diphenhydramine (Benadryl) can cause drowsiness. Montelukast can also cause drowsiness in some people. Combining them may worsen this sedative effect, making it unsafe to drive or operate heavy machinery. It's often recommended to opt for non-drowsy alternatives like cetirizine (Zyrtec) for managing allergy symptoms alongside montelukast.

• Warfarin (Jantoven): An anticoagulant used to prevent blood clots. There is evidence that montelukast can increase the activity of certain enzymes that remove warfarin, potentially making warfarin less effective. Patients taking this combination may require more frequent monitoring of their blood's clotting ability (INR).

• Gemfibrozil (Lopid): This medication for high cholesterol can also interfere with montelukast's metabolism. Healthcare providers may need to monitor the patient's response to montelukast more closely if they are taking gemfibrozil.

Herbal Supplements and Other Considerations

Herbal supplements and other substances can also pose a risk for interactions. Their natural origin does not mean they are always safe to combine with prescription drugs.

• St. John's Wort: This herbal supplement, used for mood and depression symptoms, can reduce the effectiveness of montelukast. If a patient's condition isn't responding well, a doctor might advise stopping the herbal supplement.

• Cannabis (Marijuana) and CBD: Some reports suggest that cannabis and its derivatives, like CBD, can increase the level of montelukast in the body, potentially increasing the risk of side effects. Always inform your doctor about any cannabis or CBD product use.

Comparing Montelukast Interactions

Medication Type	Specific Examples	Type of Interaction	Potential Outcome
Anticonvulsants	Carbamazepine, Phenobarbital, Phenytoin	Increased drug metabolism	Reduced montelukast efficacy
Antibiotics	Rifampin	Increased drug metabolism	Reduced montelukast efficacy
Anticoagulants	Warfarin	Increased drug metabolism	Reduced warfarin efficacy
Fibrates (Cholesterol)	Gemfibrozil	Impaired drug metabolism	Altered montelukast levels
Herbal Supplements	St. John's Wort	Increased drug metabolism	Reduced montelukast efficacy
Pain Relievers (NSAIDs)	Aspirin, Ibuprofen (for AERD)	Worsening of asthma symptoms	Increased respiratory distress
First-Gen Antihistamines	Diphenhydramine (Benadryl)	Additive sedative effects	Increased drowsiness, dizziness

Taking Precautions with Montelukast

Navigating these potential drug interactions requires careful communication and proactive management with a healthcare team. Here are some steps to take to ensure safety and effectiveness:

1. Keep a comprehensive list of all medications: This includes prescription drugs, over-the-counter medications, vitamins, and herbal supplements. Share this list with every healthcare provider and pharmacist.
2. Report any changes in symptoms: If you notice that your asthma or allergy symptoms worsen, or if you experience new side effects after starting a new medication, contact your doctor immediately.
3. Use an online drug interaction checker: Utilize reliable online tools to cross-reference your medications. This can serve as a preliminary check but should not replace professional medical advice. A good resource for this is Drugs.com.
4. Educate yourself on food and supplement interactions: Some foods and supplements, as mentioned, can impact how montelukast works. Being informed can help prevent unexpected issues.

Conclusion

While montelukast is a highly effective treatment for asthma and allergies, being aware of potential drug interactions is critical for patient safety and treatment efficacy. Key interactions involve medications that affect liver enzymes, such as certain anticonvulsants and rifampin, which can reduce montelukast's concentration. Other important considerations include avoiding NSAIDs if you have AERD and understanding the increased sedative effects when combining montelukast with certain antihistamines. Always maintain an open dialogue with your healthcare provider about all substances you are taking. This proactive approach ensures that your treatment plan remains safe and effective, minimizing risks and maximizing therapeutic benefits.

References

• Healthline. Montelukast Interactions: Other Medications, Alcohol, and More. https://www.healthline.com/health/drugs/montelukast-oral-forms-interactions
• Drugs.com. Montelukast Patient Tips: 7 things you should know. https://www.drugs.com/tips/montelukast-patient-tips
• Drugs.com. Montelukast: Uses, Dosage, Side Effects & Warnings. https://www.drugs.com/montelukast.html

Frequently Asked Questions

Can I take ibuprofen or aspirin with montelukast?

Most people can, but if you have aspirin-exacerbated respiratory disease (AERD), you should avoid NSAIDs like ibuprofen and aspirin because they can trigger or worsen your asthma symptoms.

Does montelukast interact with seizure medications?

Yes, certain seizure medications like carbamazepine, phenytoin, and phenobarbital can interact with montelukast by increasing its metabolism in the body, potentially making it less effective.

Is it safe to take montelukast with antibiotics?

Most antibiotics are safe to take with montelukast. However, the antibiotic rifampin is an exception, as it can make montelukast less effective. Always tell your doctor if you are prescribed rifampin.

What about taking montelukast with antihistamines like Benadryl?

While there is no direct interaction, combining montelukast with a first-generation antihistamine like diphenhydramine (Benadryl) can increase drowsiness. Non-drowsy alternatives are often recommended.

Can herbal supplements cause problems with montelukast?

Yes, some herbal supplements can interact. For example, St. John's Wort can make montelukast less effective. Always discuss any supplements with your doctor.

I am on a blood thinner. Is montelukast safe?

If you take warfarin, montelukast may increase the rate at which your body clears the anticoagulant, potentially making it less effective. Your doctor will likely increase monitoring of your blood's clotting ability.

Does montelukast interact with cholesterol medications?

Yes, gemfibrozil, a medication used for high cholesterol, can affect montelukast's levels. Your healthcare provider should monitor this interaction closely.