Yes your right it was more the Imuran (azathioprine) I was thinking of just sort of lumped them together.
"While having treatment with azathioprine you should avoid exposing your skin to strong sunlight and sunbeds. Use clothing and a sunscreen with a high protection factor to protect your skin. This is because long-term or intense immunosuppressive treatment can increase the risk of developing lymphomas and other cancers, particularly skin cancer. Discuss this with your doctor."
Also preds have affected my skin quite badly so have to be a bit careful.