Isotretinoin Adverse Reaction clinical trials

Oral Isotretinoin and Covid-19 Infection

There is a theoretical risk that the nasal mucosal dryness caused by oral retinoid medications may increase the risk of patients becoming infected with Covid-19. Isotretinoin is a drug used commonly in dermatology, usually for management of acne and occasionally for management of other dermatological diseases. The most common side effect of oral isotretinoin is mucocutaneous dryness, which can lead to nasal dryness and crusting. Isotretinoin is derived from vitamin A and produces this side effect by arresting the cell cycle of mucus secreting cells in the nasal cavity. The mucus usually secreted moisturises the nasal cavity and provides a protective, lubricating layer overlying the cilia. Cilia and nasal mucous are both believed to have roles in defence against infection and immunity. Hence it was postulated at the start of the pandemic that the effect this medication has on the nasal environment may increase the likelihood of contracting a disease spread by droplet or aerosol particles. In March 2020 we established a departmental Excel database of our patients on oral retinoid medications in order to track those currently receiving treatment. The database includes people taking isotretinoin, alitretinoin and acitretin. The greatest number of patients in this database are in the isotretinoin group and patients taking isotretinoin tend to be a relatively young and fit population. Acitretin on the other hand is often used in an older population who may have other underlying disease comorbidities. There were only a very small number of patients taking alitretinoin in the database. In order to limit confounding variables and provide as clear a result as possible, it was decided to limit this study to comparing the group of patients taking isotretinoin, aged 16-40years, with an age-matched background population from NHS Grampian. This study would examine the electronic patient record of patients aged 16-40years, taking isotretinoin between March and October 2020 and compare their rates of Covid-19 infection, hospitalisation and complications with the rates of the local age-matched background population. Persons taking isotretinoin in the time period would be excluded from the background population. As Covid-19 is a new disease, the existing research literature on this specific topic is extremely limited, and so far this study would be the first in this area.