Montelukast (Singulair) Can Cause Psychiatric Symptoms
Yes, montelukast (Singulair) can cause psychiatric symptoms, and this risk is significant enough that the FDA has issued specific warnings about these adverse effects.
Evidence for Psychiatric Side Effects
The FDA drug label for montelukast (Singulair) explicitly lists neuropsychiatric events as a recognized adverse effect 1. These include:
- Agitation and aggressive behavior
- Anxiety and depression
- Dream abnormalities and hallucinations
- Insomnia and irritability
- Restlessness and somnambulism (sleepwalking)
- Suicidal thinking and behavior (including suicide)
- Tremor
The FDA label specifically states that "patients and prescribers should be alert for neuropsychiatric events" and that "prescribers should carefully evaluate the risks and benefits of continuing treatment with Singulair if such events occur" 1.
Severity and Frequency
The risk of psychiatric symptoms is significant enough that:
- In 2020, the FDA strengthened existing warnings by adding a boxed warning (their strongest warning) about serious behavior and mood-related changes with montelukast 2
- The FDA has stated that "the benefits of montelukast may not outweigh the risks, especially when the symptoms are mild and can be adequately treated with other medications" 2
Pharmacovigilance data indicates that:
- Psychiatric adverse events account for approximately 20% of all adverse events reported for montelukast 3
- Analysis of the FDA Adverse Event Reporting System found significantly elevated reporting odds ratios for suicidal ideation (21.5) and depression (8.2) 4
- Worldwide data from WHO's VigiBase shows that neuropsychiatric disorders are more frequently reported for children than adults 5
Age-Related Differences
The type of psychiatric symptoms may vary by age group:
- Infants (<2 years): Primarily sleep disorders
- Children (2-11 years): Mainly depression/anxiety
- Adolescents (12-17 years): Suicidal behavior and depression/anxiety 5
Clinical Implications
When considering montelukast therapy:
- Screen for pre-existing psychiatric conditions before prescribing
- Monitor closely for the emergence of psychiatric symptoms during treatment
- Consider discontinuation if psychiatric symptoms develop
- Evaluate risk-benefit ratio carefully, especially for mild conditions that could be treated with alternative medications
- Inform patients and families about potential psychiatric side effects
Recent Research Perspective
A 2023 systematic review found that while montelukast is not consistently associated with suicide-related events or depression in large observational studies, there may be associations with anxiety and sleeping disorders, particularly in older adults 6. However, pharmacovigilance studies consistently show disproportionate reporting of psychiatric events.
Drug Interactions
The risk of neuropsychiatric events may be increased when montelukast is combined with other medications that have similar side effect profiles. For example, a case report documented worsening neuropsychiatric symptoms when montelukast was added to efavirenz therapy 7.
Conclusion
Montelukast can cause psychiatric symptoms ranging from sleep disturbances to severe manifestations like suicidal ideation, and this risk is acknowledged in the FDA black box warning. Healthcare providers should weigh these risks against potential benefits, particularly in patients with mild symptoms that could be managed with alternative treatments.