Methotrexate (the active ingredient in your medication) is commonly used long-term for psoriasis, but it requires careful medical supervision to ensure safety. To use it safely over the long term, you must have regular blood tests to monitor your liver, kidneys, and blood counts. Your doctor will likely prescribe a folic acid supplement to help minimize side effects. It is also crucial to avoid alcohol, as it can increase the risk of liver damage, and inform your doctor about any other medications you take. Please continue regular follow-ups with your dermatologist to safely manage your treatment.