Author Affiliations
Case Presentation
A 42–year–old male presented at the outpatient clinic with breathing difficulty, productive cough, and nasal congestion. On examination, vitals were normal, the patient was lethargic, and on chest examination, there was bilateral air entry on both sides of the lung with no abnormal sounds. At the clinic, the patient improved on symptomatic treatment with Ventolin (Salbutamol) and Pulmicort (Budesonide) nebulization. He had a history of allergic rhinitis, which was well controlled on levocetrizine and montelukast for the past 1 year. The patient was stable at the time of discharge and was prescribed xylometazoline hydrochloride nasal spray 1 puff each nostril thrice daily for 3 days only, levocetrizine 5mg once daily for 10 days, and montelukast 10mg once daily for 10 days. The patient mentioned that for the past 2 weeks, he had been getting headaches on/off, feeling restless at times. He was counseled that the following symptoms could be a side effect of montelukast, and a neurology review is recommended. The patient agreed to an outpatient appointment with a neurologist.
Pearl
Montelukast
Generic name: Singulair – commonly used brand name.
Indications: Treatment of Allergic or Perennial rhinitis, Prophylaxis, and treatment for chronic asthma.
Available formulation at the pharmacy: 10 mg tablet
Mechanism of action: Leukotrienes are produced by various cells, including macrophages, eosinophils, basophils, and mast cells, which are then involved in inflammatory processes associated with asthma and allergies. Leukotrienes released can cause airway edema, smooth muscle contraction, and impairment of normal cellular activities. Montelukast is a highly selective leukotriene receptor antagonist. Hence, it binds to the leukotriene receptor and inhibits the inflammatory process.
Adverse effects of montelukast:
Common adverse reactions: Headache
Rare adverse reactions: Mood swings, restlessness, aggressive behavior, suicidal ideations
Association of montelukast with neuropsychiatric manifestations: The mechanism is not fully understood, but several theories have been suggested:
Montelukast blocks leukotriene receptor. Leukotrienes may play a role in mood regulation, and altering that activity may cause mood swings.
Montelukast can cross the blood-brain barrier and may affect brain chemistry, and mood-regulating neurotransmitters such as dopamine and serotonin.
Individually, patients may react differently to montelukast, depending on genetic and environmental factors. Montelukast may not be the direct cause of the neuropsychiatric side effects, but it may play a role in unmasking the symptoms.
Montelukast is not the preferred first-line treatment in both asthma and seasonal allergies due to its neuropsychiatric effects. They are usually used in patients who are not improving on the first line of management.
In case a patient is on montelukast and is complaining of headache, restlessness, insomnia, or other abnormal behavior, a change in medication and a specialist review are required. Usually, headaches caused by Montelukast go away after the first week of taking Montelukast. If the headache persists, consult a specialist, and usually this leads to stopping montelukast in general for such patients. Usual treatment includes staying hydrated by drinking plenty of fluids, and if required, one can take paracetamol to alleviate the headache. Limiting alcohol consumption, as excessive alcohol may worsen headaches.
Educational Resources
Acknowledgments
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Funding
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Author Information
Nafi Samira
Department of General Medicine
Department of Health, Abu Dhabi, UAE
Email: ns2435706@gmail.com
Author Contribution
The author contributed to the conceptualization, investigation, and data curation by acquiring and critically reviewing the selected articles and was involved in the writing – original draft preparation and writing – review & editing to refine the manuscript.
Informed Consent
The informed consent form was taken from the patient.
Conflict of Interest Statement
Not applicable
Guarantor
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DOI
Cite this Article
Samira N. Montelukast, A Savior for Your Allergies – Could It Be the Reason for the Headaches and Mood Swings? medtigo J Neurol Psychiatr. 2025;2(2):e3084223. doi:10.63096/medtigo3084223 Crossref
