Impact of antibiotics on smell dysfunction

Abstract

ObjectiveViral or bacterial respiratory infections can cause long-lasting olfactory dysfunction. Antibiotic therapy is indicated in severe cases; however, it is unclear whether antibiotic use produces a positive, negative, or null effect on olfactory function. This retrospective study sought to determine whether antibiotic use has an influence on odor identification and detection threshold test scores of patients with smell dysfunction secondary to upper respiratory infections (URIs), lower respiratory infections (LRIs), or rhinosinusitis.MethodsData from a total of 288 patients presenting to the University of Pennsylvania Smell and Taste Center were evaluated.ResultsPatients with a URI etiology who had taken bactericidal antibiotics had lower detection thresholds than did patients who had not taken antibiotics (P < 0.023; analysis of covariance with age and time since infection onset as covariates). Moreover, thresholds were lower for bactericidal antibiotic users than for bacteriostatic antibiotic users with either URI (P = 0.023) or rhinosinusitis (P = 0.028) etiologies. No meaningful influences of antibiotics on the odor identification test scores were evident.ConclusionsThese findings, which need to be confirmed in prospective double-blind studies, suggest that bactericidal antibiotic therapy may be beneficial in mitigating, at least to some degree, chronic decrements in smell sensitivity due to URIs and rhinosinusitis.

Doxycycline Improves Quality of Life and Anosmia in Chronic Rhinosinusitis With Nasal Polyposis: A Randomized Controlled Trial

“…Doxycycline reduces bacterial colonization and therefore decreases the inflammation of sino-nasal mucosa. 20 We believe that combination of the above-mentioned properties improved hyposmia in our participants. However, more investigations are needed to define the exact involved mechanism.…”

Olfactory‐Related Adverse Events: An Analysis of the Food and Drug Administration Adverse Events Reporting System

“…Viral or bacterial upper respiratory infections can result in OD, and in severe cases, antibiotic therapy is indicated which complicates the relation to ORAE. In an analysis of bactericidal antibiotic use on OD in patients with an upper respiratory etiology, studies found lower detection thresholds in patients who had not taken antibiotics 20 . Moreover, thresholds were lower for bactericidal antibiotic users than for bacteriostatic users.…”

“…In an analysis of bactericidal antibiotic use on OD in patients with an upper respiratory etiology, studies found lower detection thresholds in patients who had not taken antibiotics. 20 [3.01, 3.18]) were noted to have significant signals for hyposmia and parosmia. It has been well-established that the olfactory sensory neural pathway includes numerous brain regions implicated in the pathophysiology of several neuropsychiatric disorders, such as depression, schizophrenia, autism spectrum disorder, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder.…”

Olfactory dysfunction in COVID-19: pathology and long-term implications for brain health

“…The location of the neuroepithelium at the interface of the environment places its cells at risk from damage from viruses [74], bacteria [93], nanoparticles [94], and other airborne xenobiotics [95]. Such damage is well established [96], with some viruses being capable of penetrating the brain from this region [74] (Box 3).…”