“Normally, cortisol levels oscillate in response to the circadian rhythm; however, stress can significantly disrupt the cycle,” explains dermatologist Keira Barr, M.D. “During periods of increased stress, cortisol levels rise significantly, which can have a major impact on your immune system.” “Cortisol both decreases the barrier function of the skin and increases the sensitivity of nerve fibers in the skin,” Villafranco says. “It also activates a local stress response system within the skin, causing mast cells to release histamine and cytokines, which translates to itching, redness, and swelling.” One study on 529 medical students found that the more stressed-out members of the cohort were more likely to develop oily, waxy patches or flakes on the scalp and rashes on the face1 because of these mechanisms. According to Joshua Zeichner, M.D., director of cosmetic and clinical research in the department of dermatology at Mount Sinai Hospital, stress is also associated with the development of hives—the same type of spots that develop when you have an allergic reaction. These raised, blotchy, red welts can vary in size and appear all over the body. Sometimes hives first manifest as general skin swelling in one area and then disappear and reappear elsewhere. Hives are often itchy or have a tingling, burning sensation. For people with existing skin conditions, stress can also worsen symptoms or cause more flare-ups. One 2013 medical review found that stress seems to exacerbate atopic dermatitis2 by impairing the immune response and skin barrier function, while another 2018 review concluded that it’s a big trigger for both the onset and exacerbation of psoriasis3. If you already have a rash and suspect stress is involved, there are a few ways to find relief: You can apply a cool compress to itchy, inflamed patches or soak in a lukewarm bath or cool shower. Again, if your rashes don’t improve with home triage, it might be time to check in with your doctor to see if they can recommend any anti-inflammatory creams or other treatments.
