Trial reportInternational forum of allergy & rhinology2023
Use of platelet-rich plasma for COVID-19-related olfactory loss: a randomized controlled trial.
Trial report in International forum of allergy & rhinology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 3 registered trials, which are not on this map. Cited by 33 papers, 4 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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.
Intranasal Injection of Platelet-rich Plasma Versus Saline for Treatment of Olfactory Dysfunction
Randomized Clinical Trial of Intranasal Injection of Platelet-Rich Plasma for Treatment of Parosmia
The Effect of Platelet-rich Plasma and Hyaluronic Acid Nasal Injection in the Treatment of Traumatic Olfactory Dysfunction
Who cites it
33 citing papers in PubMed, 4 syntheses or guidelines pooled it, 60 citations in OpenAlex.
- Navigating the efficacy, safety and outcome of intranasal platelet-rich plasma for persistent olfactory loss: 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
- Short-term efficacy of platelet-rich plasma in the treatment of persistent olfactory dysfunction: 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 · 2025Pooled it
- Treatment of COVID-19 Associated Olfactory Dysfunction: A Systematic Review.Current allergy and asthma reports · 2024Pooled it
- Utilization and efficacy of platelet-rich plasma and platelet-rich fibrin in otolaryngology: a systematic evidence-based review.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 · 2024Pooled it
- Long-term Outcomes of PRP Injections for Post-viral Olfactory Loss: A Prospective Cohort Study.International forum of allergy & rhinology · 2025Trial
- Use of platelet-rich plasma for COVID-19-related olfactory loss: a randomized controlled trial.International forum of allergy & rhinology · 2023Trial
- Regenerating smell in neurodegenerative disease -translating theory into therapy.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 · 2026Review
- Vitamin A-Containing Intranasal Drops Improve Odour Detection Threshold.ORL; journal for oto-rhino-laryngology and its related specialties · 2026Article
- Platelet-Rich Plasma-Derived Exosome Olfactory Cleft Injection for Treating Traumatic Olfactory Dysfunction.Diagnostics (Basel, Switzerland) · 2026Article
- Review
- Topical Anesthesia and Olfactory Capability: A Pilot Study.Laryngoscope investigative otolaryngology · 2025Article
- Review
- Enhancing the Outcomes of Temporalis Fascia Tympanoplasty Using Autologous Platelet-Rich Plasma and Gel: A Randomized Controlled Trial.Journal of personalized medicine · 2025Article
- Article
- Review
- Role and Mechanism of Olfactory Stem Cells in the Treatment of Olfactory Disorders.Stem cells international · 2025Review
- Effectiveness of platelet-rich plasma in long-lasting post-viral olfactory dysfunction: a case-series.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 · 2024Article
- Polyunsaturated Fatty Acids as Potential Treatments for COVID-19-Induced Anosmia.Biomedicines · 2024Review
- Review
- Long-term olfactory loss post-COVID-19: Pathobiology and potential therapeutic strategies.World journal of otorhinolaryngology - head and neck surgery · 2024Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 2 institutions in 1 country.
Funding
Abstract
introductionThe current study evaluated the use of platelet-rich plasma (PRP), an autologous blood product with supraphysiologic concentrations of growth factors, in the treatment of prolonged coronavirus disease 2019 (COVID-19)-related smell loss.
methodsThis multi-institutional, randomized controlled trial recruited patients with COVID-19 who had objectively measured smell loss (University of Pennsylvania Smell Identification Test [UPSIT] ≤ 33) between 6 and 12 months. Patients were randomized to three intranasal injections of either PRP or sterile saline into their olfactory clefts. The primary outcome measure was change in Sniffin' Sticks score (threshold, discrimination, and identification [TDI]) from baseline. The secondary end point measures included responder rate (achievement of a clinically significant improvement, ≥5.5 points TDI), change in individual TDI olfaction scores, and change in subjective olfaction via a visual analog scale.
resultsA total of 35 patients were recruited and 26 completed the study. PRP treatment resulted in a 3.67-point (95% CI: 0.05-7.29, p = 0.047) greater improvement in olfaction compared with the placebo group at 3 months and a higher response rate (57.1% vs 8.3%, odds ratio 12.5 [95% exact bootstrap confidence interval, 2.2-116.7]). There was a greater improvement in smell discrimination following PRP treatment compared with placebo but no difference in smell identification or threshold. There was no difference in subjective scores between PRP and placebo. No adverse effects were reported.
conclusionOlfactory function following COVID-19 can improve spontaneously after 6 months and can improve to a greater extent with PRP injection. These data build on the promise of PRP to be a safe potential treatment option for patients with COVID-19-related smell loss, and larger-powered studies will help further assess its efficacy.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
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.