Neuropsychiatric problems with Asthma medication – Montelukast (Singulair)

Montelukast is an oral leukotriene receptor antagonist. It is indicated for patients 6 months and older:

• for the treatment of asthma as add-on therapy in those patients with mild to moderate persistent asthma who are inadequately controlled on inhaled corticosteroids and in whom “as-needed” short acting beta-agonists provide inadequate clinical control of asthma.
• in those asthmatic patients in whom montelukast is indicated, montelukast can also provide symptomatic relief of seasonal allergic rhinitis.
• for the prophylaxis of asthma in which the predominant component is exercise-induced bronchoconstriction.

It’s estimated around 14 million prescriptions are filled out by medics for the drug each year.

In the UK, between 2014 and 2018, MHRA received 219 reports of these suspected side effects.

And since the drug was first introduced in the UK, they have noted 639 reports of side effects in total.

Medicines and Healthcare products Regulatory Agency (MHRA) alerted healthcare professionals, patients and caregivers for neuropsychiatric reactions in patients taking montelukast.

Most common events reported in adults, adolescents, and children are sleep disturbances, depression and agitation, disturbances of attention or memory, and very rarely, hallucinations and suicidal behaviour. 

However, nightmare/night terrors, aggression, and behaviour changes are more frequently reported in the paediatric population.

The EU review also evaluated very rare reports of cases of speech impairment (dysphemia), described as ‘stuttering’. Most of the cases were reported in children younger than 5 years, occurred shortly after montelukast was started (median time to onset 8 days) and sometimes occurred in conjunction with other suspected neuropsychiatric events. Where information was provided, in most cases the events resolved on stopping treatment.

The product leaflet has been updated with new safety information and the patients/caregiver always read the leaflet that accompanies medicines, and talk to a healthcare professional if you suspect any serious reactions to montelukast.

*Source: MHRA drug safety alerts