ergocalciferol + hydroxychloroquine + methotrexate

This is a combination of three drugs—ergocalciferol (vitamin D2), hydroxychloroquine, and methotrexate. - **Ergocalciferol** is a form of vitamin D used to treat or prevent vitamin D deficiency, hypoparathyroidism, rickets, and familial hypophosphatemia. It works by being converted in the body to active metabolites that bind the vitamin D receptor, promoting calcium and phosphate absorption for bone health[1][3][4][7]. - **Hydroxychloroquine** is an antimalarial agent also used as a disease-modifying antirheumatic drug (DMARD) for autoimmune diseases such as rheumatoid arthritis and lupus. It modulates immune activity by interfering with lysosomal activity and antigen presentation in immune cells (not detailed in search results but well established). - **Methotrexate** is an antimetabolite and antifolate agent used at low doses as a DMARD for inflammatory conditions like rheumatoid arthritis, psoriatic arthritis, juvenile idiopathic arthritis, vasculitis, myositis, systemic sclerosis; at higher doses it treats various cancers. Methotrexate inhibits dihydrofolate reductase (DHFR), reducing DNA synthesis in rapidly dividing cells; it also suppresses immune function[6][8][10]. This combination may be prescribed together for certain autoimmune or rheumatologic conditions where immunosuppression plus bone protection are needed.