Entyvio (vedolizumab) has not been shown to cause hair loss in clinical trials. Hair loss has not been identified as a potential side effect of the medication.

However, there have been a few case reports of Entyvio, which treats ulcerative colitis and Crohn's disease, triggering psoriasis, which can result in hair loss.

• In one case reported in The Spanish Journal of Gastroenterology in 2018, a patient with Crohn’s disease experienced mild hair loss shortly after starting treatment with Entyvio, which eventually progressed to severe scalp psoriasis and more extensive hair loss. After stopping the drug, the patient’s condition improved, and hair regrowth occurred.
• In another case reported in Inflammatory Bowel Diseases in 2017, a patient with ulcerative colitis reportedly developed psoriasis shortly after beginning Entyvio, although the scalp was not affected.

While hair loss is unlikely to be caused by Entyvio, there are links between hair loss and inflammatory bowel disease (IBD), which is treated with Entyvio, as well as other medications used to treat IBD.

Compared to the general population, people with inflammatory bowel diseases appear more likely to develop alopecia areata, an autoimmune disease characterized by hair loss on the scalp and other body parts. It is not well understood why IBD is linked to hair loss, but it could be due to various factors, including the disease itself, vitamin deficiencies and certain medications.

Methotrexate and infliximab are among the drugs that have been rarely linked to hair loss in patients with inflammatory bowel disease.