1. The age range of patients responding to the survey was 28-85 with a mean of 58\(\pm\)12 years with the duration of their disorder less than 5 years in 63% of cases. 2. Patients experience variable treatment, if at all, for post-viral olfactory loss 3. If treatment is given oral and/or intranasal steroids are typically given. 4. Several patients reported receiving imaging despite this not being clinically useful when there is a clear history and normal examination. 5. Over two thirds of patients experience parosmia and up to 5 years of the onset of the problem were still actively seeking a solution.

IntroductionLoss of smell is a common complaint in adults and yet has been underestimated. Anosmia, complete loss of smell, is thought to affect at least 1-5% of the population[1]. Based on European estimates, anosmia is more prevalent than profound hearing loss or blindness in the UK. Causes for olfactory loss are varied but the main diagnostic groups include sinonasal disease (62%) and post-infectious olfactory dysfunction (PIOD) (11%)[2]. Olfactory dysfunction has now emerged as a key symptom in the coronavirus pandemic and it is possible we may see a cohort of patients with lasting problems following the peak of the Covid-19 impact[3, 4]. Historically, there is wide variation in clinical practice reported by clinicians to patients on prognosis or treatment[5]. Guidelines for the overall management of olfactory disorders now exist in the Position Paper on Olfactory Dysfunction[6] and recently the British Rhinological Society has produced a consensus statement on managing Covid-related PIOD[7] but the impact of those guidelines have yet to penetrate routine clinical practice.Previously published data has shown the high impact on quality of life experienced by olfactory disorder patients, including depression, anxiety, impairment of eating experience, feelings of isolation and relationship difficulties[8, 9]. Most patients suffer a loss of flavour perception which can adversely affect their appetite, but this can be made even worse when parosmia is also present. Given the number of potential treatment options for PIOD that have been proposed but yet to undergo formal evaluation through a randomised clinical trial[10], there is a pressing need to deliver more RCTs in this area. A recent German study has highlighted Vitamin A as a potential therapeutic agent for further evaluation[11]. In anticipation of setting up a clinical trial to evaluate the role of vitamin A intranasally for PIOD we sought to generate evidence of need to funders through Public and Patient Involvement (PPI) in partnership with the charity Fifth Sense that represents patients affected by Smell & Taste disorders in the UK (www.fifthsense.org.uk).The aim of this study was to characterise the experience of patients with PIOD in terms of the treatment they received in order to demonstrate any unmet need.