Methotrexate and bone loss

Methotrexate is a medication used for conditions like rheumatoid arthritis, psoriatic arthritis, and some cancers at higher doses. It works by interfering with cell growth and reducing inflammation, but it can also affect bone-forming cells and slow new bone formation, especially with long-term use or higher doses. The underlying inflammatory disease itself (like rheumatoid arthritis) also contributes to bone loss, so it can be hard to separate the drug's effect from the illness it treats.

Bone changes linked to methotrexate have sometimes been called 'methotrexate osteopathy,' which can include bone pain, low bone density, and rarely stress fractures, though this is uncommon at the lower weekly doses typically used for autoimmune conditions. People on long-term methotrexate, particularly those with other risk factors like steroid use, menopause, or inactivity, may have added fracture risk worth discussing with their doctor.

If you take methotrexate, your prescriber may monitor your bone health with tools like a DEXA scan, especially if you have other risk factors. Decisions about calcium, vitamin D, weight-bearing activity, or any changes to your medication should be made with your doctor or rheumatologist, who can weigh the benefits of treating your underlying condition against any bone-related concerns.