The short answer is that experts warn patients not to stop or change dosage of medication without calling their doctors.

The long answer is that we don’t know whether taking immunosuppressant drugs further increases the risk of catching COVID-19. But Michael George, MD, a rheumatologist and assistant professor of medicine and epidemiology at the University of Pennsylvania, in Philadelphia, says that in relation to viruses in general, limited data suggest some of the drugs used to treat autoimmune and inflammatory types of arthritis – biologics (for example, Remicade, Enbrel and Cimzia), JAK-inhibitors (Xeljanz, Olumiant and RINVOQ), and corticosteroids (prednisone) – may contribute to higher risk or severity of viral infection. A recent large study of people with cardiovascular disease found that hydroxychloroquine (Plaquenil) does not increase the risk of infection and methotrexate increases the risk of infection only slightly.
The concern with immune suppression is that the virus could replicate more freely and cause more severe or extensive disease, says Dr. Winthrop. For this reason, it’s important if you are taking these medications to contact your doctor right away if you think you’ve been exposed or are experiencing flu-like symptoms. (See question addressing symptoms.) Be sure to state that you are taking immune-suppressing drugs.
Source: Arthritis Foundation