Serious Dermatologic Adverse Events Rare With Hydroxychloroquine

By Anne Harding

July 16, 2020

NEW YORK (Reuters Health) - Hydroxychloroquine can be associated with serious dermatological adverse events, but they are rare, new findings show.

Steven-Johnson Syndrome/Toxic Epidermal Necrolysis (SJS-TEN), skin necrosis and vasculitis accounted for 3.6% of adverse reactions to the antimalarial reported to the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS), Dr. Shari Lipner of Weill Cornell Medicine in New York City and her colleagues found.

"Our data shows that hydroxychloroquine is a relatively safe drug with mostly mild associated adverse events. However, it is paramount that physicians prescribing hydroxychloroquine understand the more serious adverse events associated with this drug to properly counsel patients on warning signs for these more dangerous rashes," Dr. Lipner told Reuters Health by email. Physicians should also closely monitor patients on the drug, she added.

Hydroxychloroquine has been approved by the Food and Drug Administration for treating malaria, systemic lupus erythematosus and rheumatoid arthritis, and has been used off-label for treating some dermatologic and rheumatologic conditions, the researcher explained in the Journal of the American Academy of Dermatology.

"It has recently garnered interest as a potential treatment for COVID-19, with inconclusive efficacy," she added.

Dr. Lipner and her team retrospectively reviewed 1970-2019 data from FAERS on adverse reactions linked to hydroxychloroquine, analyzing 9,242 cases. Drug hypersensitivity reactions, rash and dermatitis were the most common events, accounting for 61.4% of cases, while pruritus (4.7%) and urticaria (4.5%) were also relatively common.

Nail changes accounted for 1.9% of reports, skin hyperpigmentation 1.8%, mucosal disorders 1.2%, and hair disorders 0.5%.

Among the 5,758 patients with reported ages, 46.4% were 41-64 years old and 28% were 65-85 years old. Female patients represented 83.7% of the 8,704 cases in which sex was reported.

"Many of our findings are similar to those adverse events associated with hydroxychloroquine reported in the previous literature," Dr. Lipner said. "However, in our study we found that skin hyperpigmentation was much less common than that reported in previous reports and that nail changes were much more common."

While the FAERS is "robust," "it is important to note that this data is self-reported by physicians, pharmaceutical companies, and patients, without corroboration," Dr. Lipner added. "Some case information, dosing/cumulative dosing, and hydroxychloroquine prescribing by year were not available. Therefore, future studies will focus on collecting prospective data on adverse events in patients taking hydroxychloroquine."

SOURCE: Journal of the American Academy of Dermatology, online July 8, 2020.