Methotrexate, the decades-old psoriasis treatment still commonly prescribed for psoriasis and psoriatic arthritis, is getting more attention recently as evidence seems to be building that injecting methotrexate under the skin may be superior to oral administration for psoriasis patients. But as with so many other treatment issues, it is not an open-and-shut case.
The vast majority of psoriasis and psoriatic arthritis patients on methotrexate take it in pill form weekly. But both anecdotally and in small studies that do not have the size or study design to definitively prove the matter, it appears that injection of methotrexate under the skin (subcutaneously) can provide superior results to the same dose taken in pill form, without an increase in side effects, and with a reduction in the stomach upset that many patients experience at higher doses of oral methotrexate. (This also appears to be the case for methotrexate used in rheumatoid arthritis treatment.)
Even in this age of new treatment options, methotrexate continues to be a low-cost, effective treatment for many people with psoriasis and psoriatic arthritis. It is often used successfully in combination with other treatments. If you are largely satisfied with your treatment regimen that includes oral methotrexate, but wish it could be a bit better, you could ask your healthcare provider about switching to methotrexate by injection. The needle is incredibly thin, and while the process is a bit more cumbersome than a pill (since there is no pre-filled syringe or auto-injector for methotrexate), it can be learned quickly. You would also want to consider your out-of-pocket costs for each option.
Research meta-analysis: Update on subcutaneous methotrexate for inflammatory arthritis and psoriasis