A 16-year-old Caucasian female presented to the pulmonary clinic for a followup on her asthma. Due to the worsening of allergy-related symptoms, therapy with montelukast 10 mg daily was started and resulted in good relief of the patient’s symptoms. In the nights following initiating therapy with montelukast, the patient’s mother reported daily parasomnias in the form of sleeptalking and sleepwalking. Montelukast was discontinued, and that resulted in absence of the parasomnias. In a second attempt montelukast was reinstituted to control the patient’s symptoms. Parasomnias were immediately reported after resuming therapy. Montelukast was then discontinued indefinitely. Our patient has never had any history of parasomnias, and since the discontinuation of montelukast, parasomnias were never reported again. Parasomnias in the form of sleeptalking or sleepwalking were not previously reported as adverse effects of montelukast. Alternative modalities to treat allergy-related symptoms in patients, who develop parasomnias while receiving montelukast, should be explored.
A 16-year-old Caucasian female presented to the pulmonary clinic for a followup on her asthma which has been treated with fluticasone propionate 250 mcg/salmeterol 50 mcg and albuterol sulfate inhalers. Past medical history included asthma and allergic rhinitis. There were no reported symptoms related to obstructive sleep apnea (OSA), and no history of any psychological disorders. There was no family history of sleepwalking, sleeptalking, or other forms of parasomnias. Due to the worsening of allergy-related symptoms (ARS), including allergic rhinitis, therapy with montelukast 10 mg daily was started and resulted in good relief of the patient’s ARS. In the nights following initiating therapy with montelukast, the patient’s mother reported daily parasomnias in the form of sleeptalking and sleepwalking. Montelukast was discontinued, and that resulted in absence of the parasomnias. A few days later, montelukast was reinstituted in a second attempt to control the patient’s ARS; however, sleeptalking and sleepwalking were reported again immediately after resuming therapy. Montelukast was discontinued indefinitely. Our patient has never had any history of parasomnias, and since the discontinuation of montelukast, parasomnias were never reported again. The application of Naranjo scale (Table
Naranjo algorithm | ||||
---|---|---|---|---|
Yes | No | Do not know or not done | Our patient | |
(1) Are there previous conclusive reports on this reaction? | +1 | 0 | 0 | 0 |
(2) Did the adverse events appear after the suspected drug was given? | +2 | −1 | 0 | +2 |
(3) Did the adverse reaction improve when the drug was discontinued or a specific antagonist was given? | +1 | 0 | 0 | +1 |
(4) Did the adverse reaction appear when the drug was readministered? | +2 | −1 | 0 | +2 |
(5) Are there alternative causes that could have caused the reaction? | −1 | +2 | 0 | +2 |
(6) Did the reaction reappear when a placebo was given? | −1 | +1 | 0 | 0 |
(7) Was the drug detected in any body fluid in toxic concentrations? | +1 | 0 | 0 | 0 |
(8) Was the reaction more severe when the dose was increased, or less severe when the dose was increased? | +1 | 0 | 0 | 0 |
(9) Did the patient have a similar reaction to the same or similar drugs in any previous exposure? | +1 | 0 | 0 | 0 |
(10) Was the adverse event confirmed by any objective evidence? | +1 | 0 | 0 | +1 |
| ||||
Totals | 8 |
>9: definite adverse drug reaction.
5–8: probable adverse drug reaction.
1–4: possible adverse drug reaction.
0: doubtful adverse drug reaction.
WHO-UMC causality categories | ||
---|---|---|
Causality term | Assessment criteria | Yes/no |
Certain | Event or laboratory test abnormality, with plausible time relationship to drug intake. | Yes |
Cannot be explained by disease or other drugs. | Yes | |
Response to withdrawal plausible (pharmacologically, pathologically). | Yes | |
Event definitive pharmacologically or phenomenologically (i.e., an objective and specific medical disorder or a recognized pharmacological phenomenon). | yes | |
Rechallenge satisfactory, if necessary. | Yes | |
| ||
Final outcome | Certain |
Parasomnias in the form of sleepwalking and sleeptalking are common. In a review of behavior-related experiences in clinical trials of montelukast by Philip et al., the overall behavior-related adverse experiences were infrequent [
Bygdell et al. analyzed 744 psychiatric adverse reactions among a total of 600 individual case safety reports concerning children in Sweden and found that montelukast was one of the three most frequently suspected drugs which resulted in psychiatric adverse drug reactions [
Furthermore, Wallerstedt et al. reviewed 48 reports of psychiatric disorders in children during treatment with montelukast. Psychiatric disorders reported more than once included nightmares, unspecified anxiety, aggressiveness, sleep disorders, insomnia, irritability, hallucination, hyperactivity, and a personality disorder [
Children with OSA, if not treated, frequently exhibit neurocognitive and behavioral morbidities and may benefit from treatment with leukotriene (LT) modifier therapy drugs such as montelukast [
Goldbart et al. performed quantitative polymerase chain reaction, immunohistochemistry, and Western blotting for gene and protein expression of LK receptors (LK1-R) and (LK2-R) and for concentrations of LTB4 and LTC4/D4/E4 in adenoid and tonsillar tissues from children with OSA or recurrent throat infections [
HLA and genetic susceptibilities to sleepwalking were reported by Lecendreux et al. [
The possible mechanism of this side effect of montelukast could be due to its effect on the cysteinyl leukotriene type 1 (CysLT1) receptor in the central nervous system by being a CysLT1 receptors antagonist. This speculation is supported by the review by Wang et al. of the role of CysLT1 receptors in the central nervous system related to behavior and the effects of montelukast as a CysLT1 receptors antagonist [
Parasomnias in the form of sleeptalking or sleepwalking were not previously reported as adverse effects of montelukast. Sleeptalking is an event of utterances to coherent conversation during sleep, and it is of little medical concern [
The authors declare that they have no conflict of interests.