Respiratory researchers have voiced concerns over the number of patients with asthma or COPD being prescribed sedatives in clinical practice, given the potential link with increased risk of exacerbations.

Sedatives are respiratory depressants and could therefore be an avoidable and potentially reversible cause of obstructive lung disease exacerbations, according to an article in The Lancet Respiratory Medicine [link here] by authors from Nottingham NIHR Respiratory Biomedical Research Centre.

The authors say there is a need to educate doctors in primary and secondary care on considering the potential risks sedatives pose to respiratory health, particularly as the prevalence of such medicines and polypharmacy in patients continues to surge.

Sedation and hypoventilation induced by medication can lead to subclinical aspiration, chest infection and even death, particularly in patients with obstructive lung disease and co-morbidities, but remain an “overlooked” driver of acute exacerbations, they wrote.

Opioids are known to reduce respiratory drive and muscle tone, and are also linked with an increased risk of developing pneumonia, most likely because of a higher risk of aspiration, but the authors believe other medications and mechanisms may be having the same effect.

“We hypothesise that there is also likely to be an increased risk of sedative-induced aspiration or hypoventilation events in patients taking other medications, such as pregabalin, gabapentin, and amitriptyline, which are mainly prescribed for neuropathic pain and depression,” they said.

But research on exacerbations has not really explored the potential role that commonly prescribed medicines outside of the respiratory landscape may have in fuelling exacerbations, despite the burgeoning number of sedatives prescribed in primary care, according to the article.

“On our hospital wards, we regularly see patients with acute exacerbations of either asthma or COPD admitted while on a combination of gabapentin, pregabalin, amitriptyline, and opioids; however, there is little data or disease-specific guidance on how best to manage this problem, which often starts with a prescription in primary care,” the authors said.

“More research in this area is needed to provide robust evidence for any potential association between the prescription of sedative medications and exacerbations of obstructive airways disease, especially as a study in Taiwan in 2022 concluded that the use of typical antipsychotics is associated with a dose-dependent increased risk of severe asthma exacerbation”.

Way forward

If causation is proven, then other substances with sedative effects, including cough syrups, excessive alcohol and older antihistamines should also be considered as “potentially reversible risk factors for exacerbations of obstructive lung disease”, they noted.

The authors suggested that following hospital discharge for severe exacerbation in patients on sedative medication primary care doctors should be asked to reassess the indication and dose. They should also be provided with information on the potential risks and alternative analgesics and strategies, such as physiotherapy, pain clinics and rehabilitation.

“Highlighting the risk of respiratory depression and polypharmacy in patients with chronic respiratory disease will enable general practitioners and family doctors to suggest these alternative treatments (with less risk for the individual patient), potentially reducing the number of exacerbations of obstructive lung disease,” they concluded.