COVID-19 is a virus that can affect all systems, and while most think first of it threatening our breathing, it bears a considerable burden on the skin. As doctors, we have certainly seen increased numbers of skin rashes and irritations, and there’s anecdotal evidence that it can impair wound healing. For 1 in 5 with COVID-19, a skin sign is the only symptom they get. COVID-19 skin signs fall into two categories – common conditions that have become much more common, such as urticaria, and rare conditions that have increased, such as those affecting the toes or mouth. The COVID ZOE symptom app has taken data from millions with COVID-19 symptoms. The doctors behind it, from Kings College London, have argued that skin signs are so common with COVID-19, that it should be listed as a fourth key sign of COVID-19 infection, alongside fever, cough and loss of sense of smell. It’s not clear if the virus causes these changes directly or via the immune response it provokes, but nearly half appear at the time of infection – about a third appear after infection. It’s worth noting that it’s common to get a rash after any mild viral illness, such as a cold.
COVID-19 can cause any skin rash, particularly those that are itchy. Prickly heat or chickenpox-type rash is the most common, causing small itchy red bumps or blisters, which may become weepy or crusty. It often starts on the knees, elbows, the backs of hands and the feet, then it spreads across the body, but spares the face. This often appears much later than other COVID-19 symptoms, even weeks or months later, and lasting for weeks. Urticaria, otherwise known as hives or stinging nettle-rash, is the second most common rash. This appears as itchy red blotches that come and go within hours. New ones can form anywhere on the body and face, and you may get swelling in the lips or around the eyes. It’s usually an early sign of COVID-19 infection.
Chilblains are found in Arctic explorers and any long exposure to the cold. They occur when blood vessels become inflammed in response to repeated long periods of cold conditons or if you have a problem with your blood supply. They cause a great deal of pain, sometimes itching, and are medically known as pernio. But the COVID pandemic has brought them to the fore, where they’ve become known as COVID toes or COVID fingers and occur even in warm conditions. Spots in light skin may appear red or purple, and in skin of colour they may look dark brown or black. These areas are usually very painful, especially when using them, such as walking or typing. These spots can appear weeks or months after the infection, and are more common in mild infection and those who are younger. They can last up to 3 months, and skin peels as they clear up. COVID tongue is the description for a patchy red tongue. It’s similar to a harmless condition called geographical tongue, where the surface of the tongue resembles a map. People have also reported a dry mouth, thrush or other fungal infections in the mouth. Mouth ulcers or sores may occur, and take a couple of weeks to clear up.
Urticaria is usually histamine-driven, so an anti-histamine can help clear the rash and relieve the itching. Non-sedating is best for the daytime, such as loratadine or cetirizine, and a sedating antihistamine, such as chlorphenamine, is best for itching at night. Cooling agents such as aloe vera gel or Dermacool can help ease itchy skin, especially if you keep it in the fridge. Tepid showers or baths or a cool flannel may also help. Keep any weeping or crusty rashes clean once a day and pat dry. Painkillers such as paracetamol can help with COVID toes or any other pain, and it’s fine to take ibuprofen with COVID-19 infection, too. Bonjela or antiseptic mouthwashes can be useful to help relieve oral ulcers and clear them up. If the rash or other COVID symptoms are not bothersome, keep yourself well with plenty of hydration, healthy well-balanced meals and lots of rest. This gives your body the space it needs to fight any infection, calm any immune response and recover.
If you have a painful or itchy rash that hasn’t responded to simple home measures, it’s worth seeing your doctor to discuss the next steps. This may be caused by COVID-19 – it's worth doing a test – but it can be hard to relate this to COVID-19 if it is some time since your infection, and your skin rash could have another cause. Your doctor may be able to advise on what the rash is and what may help. With urticaria, if over-the-counter anti-histamines haven’t helped, they can prescribe something stronger to ease symptoms. For COVID toes, you may need stronger painkillers in the early days. Your doctor can prescribe an anti-fungal tablet or mouth wash to treat any oral thrush. They may suggest emollients – medical grade moisturisers – to help relieve and repair skin, and a steroid cream may ease inflammation. Ultimately, most rashes resolve on their own with time, and most COVID-19 infections clear up without long-term complications. *Correct on 7 March 2022