Cutaneous Reactions after COVID-19 vaccines

This article provides an overview of cutaneous reactions after administration of COVID-19 vaccines. Cutaneous reactions post COVID-19 trials range from acute and immediate reactions to delayed reactions. The suspected triggers for the hypersensitivity reactions are the inactive ingredients, such as polyethylene glycol in mRNA vaccines and polysorbate 80 in AstraZeneca. Localized or injection-site reactions are generally self-limiting and occur within seven days. Younger, female patients were more likely to report injection-site reactions. Cutaneous reactions after the second dose occurred earlier than after the first dose. Delayed large local reactions or COVID arms have been reported at least seven days post-vaccination and generally resolve within two weeks. However, this was reported as early as four days post-AstraZeneca vaccination. Other dermatological reactions, such as pityriasis rosea-like eruptions and flares of existing cutaneous conditions occurred in mRNA and AstraZeneca recipients but not with Sinopharm. Screening questions may be used to risk stratifying vaccine recipients into low, medium or high risk of developing severe allergic reactions. Skin testing may be considered for high-risk category patients. However, negative skin testing does not rule out a subsequent allergic response. Delayed cutaneous reactions may be misdiagnosed as cellulitis, resulting in unnecessary treatment with antibiotics.