Trial reportEuropean archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery2024
Persistent COVID-19 parosmia and olfactory loss post olfactory training: randomized clinical trial comparing central and peripheral-acting therapeutics.
Trial report in European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers, 2 of them syntheses that pooled it.
What it found
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
11 citing papers in PubMed, 2 syntheses or guidelines pooled it, 12 citations in OpenAlex.
- Therapeutic effect of anti-neuroinflammatory supplement combined with olfactory training on post-covid olfactory dysfunction: a systematic review and meta-analysis.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2026Pooled it
- The effectiveness of olfactory training for chronic olfactory disorder following COVID-19: a systematic review.Frontiers in human neuroscience · 2024Pooled it
- Impacts of different treatment methods on patients with COVID-related olfactory dysfunction: a systematic review and network meta-analysis.Clinics (Sao Paulo, Brazil) · 2026Article
- Corrigendum to 'Effects of therapeutic interventions on long COVID: a meta-analysis of randomized controlled trials'.EClinicalMedicine · 2026Article
- Systematic Review of Randomized Clinical Trials for the Treatment of Long COVID Syndrome.Journal of community hospital internal medicine perspectives · 2026Article
- Clinical Practice Guideline Recommendations for Post-Acute Sequelae of COVID-19.Infection & chemotherapy · 2025Review
- Olfactory Training for Post-COVID-19 Olfactory Dysfunction: A Meta-Analysis of Efficacy and Combination Therapies.Journal of clinical medicine · 2025Review
- Effects of therapeutic interventions on long COVID: a meta-analysis of randomized controlled trials.EClinicalMedicine · 2025Article
- Therapeutic options for the treatment of post-acute sequelae of COVID-19: a scoping review.BMC infectious diseases · 2025Article
- Palmitoylethanolamide supplementation for human health: A state-of-the-art systematic review of Randomized Controlled Trials in patient populations.Brain, behavior, & immunity - health · 2025Review
- Real-World Outcomes of 3-Month Olfactory Training on Post-COVID-19 Parosmia.ORL; journal for oto-rhino-laryngology and its related specialties · 2025Article
Corrections and comments
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Authors and funding
7 authors at 5 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeAlthough COVID-19 anosmia is often transient, patients with persistent olfactory dysfunction (pOD) can experience refractory parosmia and diminished smell. This study evaluated four putative therapies for parosmia in patients with chronic COVID-19 olfactory impairment.
methodsAfter screening nasal endoscopy, 85 patients (49 female, 58%) with pOD and treatment-refractory parosmia were randomized to: (1) ultramicronized palmitoylethanolamide and luteolin + olfactory training (OT) (umPEALUT group, n = 17), (2) alpha-lipoic acid + OT (ALA group, n = 21), (3) umPEALUT + ALA + OT (combination group, n = 28), or 4) olfactory training (OT) alone (control group, n = 23). Olfactory function was assessed at baseline (T
resultsThe umPEALUT group had the largest improvement in TDI scores (21.8 ± 9.4 to 29.7 ± 7.5) followed by the combination group (19.6 ± 6.29 to 27.5 ± 2.7), both p < 0.01. The control and ALA groups had no significant change. Patients in the combination and umPEALUT groups had significantly improved TDI scores compared to ALA and control groups (p < 0.001). Rates of parosmia resolution after 6 months were reported at 96% for combination, 65% for control, 53% for umPEALUT and 29% for ALA (p < 0.001). All treatment regimens were well-tolerated.
conclusionsumPEALUT and OT, with or without ALA, was associated with improvement in TDI scores and parosmia, whereas OT alone or OT with ALA were associated with little benefit.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.