Dear Editor
We read with great interest and astonishment the article by Gupta et al 1 . We found striking that a case of alopecia areata was published as caused by isotretinoin in the journal. The common mucocutaneous side effects of the drug, including cheilitis, dry skin and mucous membranes, epistaxis or d1esquamation are predictable and dose dependent. Also, in a systematic review, where dermatologic side effects represented nearly 65% of all reported side effects, they included temporary diffuse alopecia similar to effluvium telogenum 2, 3 but cases of alopecia areata have not been reported in the biggest case series. 4 The effect of isotretinoin on the hair cycle has been studied and only a reduced anagen hair ratio has been demonstrated.5, 6 Finally, the food and drug administration of the United States of America published a report of a 20 year span of isotretinoin expected side effects regarding hair and did not found any single case of alopecia areata due to isotretinoin. 7
Alopecia areata, a well‐known autoimmune process, has been reported in two other cases as mentioned by the authors. After decades of isotretinoin use, do we really think this is a drug‐induced case? Imputability according to the algorithms of the World Health Organization or any other was not performed. 8 If a patient in COVID‐19 quarantine presents an episode of alopecia areata, could we talk about COVID‐19 ‐association?
In our opinion, isotretinoin is one of the most prescribed drugs by dermatologists, and also one of the ones with the higher success rates. It has a bad reputation among patients partly because of lack‐of‐evidence publications. We believe that the eager to publish makes us all take part in publications that do not contribute to the scientific literature in a relevant way. To prove a causal association between a drug and a secondary dermatological side effect high quality evidence (cohort studies, clinical assays…) is required and just a single case cannot be seen as a prove of a causal relation. Sometimes these associations are just casual and this should be clearly stated in this type of case reports.
We all must make an effort to prevent this practice from continuing.
CONFLICT OF INTEREST
The authors declare no conflicts of interest.
REFERENCES
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