3 to 6 weeks.
Your doctor will tell you how much medicine to use. Do not use more than directed. The correct schedule for this medicine is different for arthritis, psoriasis, and different kinds of cancer. For example, people who have arthritis or psoriasis often take this medicine only once a week.  1 Methotrexate can be taken by mouth (tablets) or by injection as follows: 2  Tablets: Methotrexate is available in 2.5 mg tablets. 3  The standard dose ranges from 6 tablets per week (15 mg) to 10 tablets per week (25 mg). 4  Injection: Methotrexate is available in a liquid (25 mg/mL) for injection. 1 Injection: Methotrexate is available in a liquid (25 mg/mL) for injection. 2  The standard dose ranges from 0.6 mL (15 mg) to 1.0 mL (25 mg) per week. 3  Patients are usually taught to self-inject People with rheumatoid arthritis may be more likely to continue treatment with methotrexate than with other DMARDs because of favorable results and tolerable side effects. Methotrexate is often the first DMARD prescribed for rheumatoid arthritis and usually provides relatively fast relief of at least some symptoms. If you can tolerate methotrexate, but it is not effective, your rheumatologist will recommend that you take another DMARD along with methotrexate (combination therapy). Why It Is Used. Methotrexate reduces inflammation caused by rheumatoid arthritis. It is the most common DMARD used to treat rheumatoid arthritis. Methotrexate may be used: 1  In the early stages of rheumatoid arthritis to prevent disease progression. 2  In combination with other medicines such as other DMARDs. How It Works. Methotrexate interferes with the production and maintenance of DNA, the genetic material in the cells of your body. It is not known exactly how methotrexate works in rheumatoid arthritis, but it can reduce inflammation and slow the progression of the disease. Why It Is Used. Methotrexate reduces inflammation caused by rheumatoid arthritis. It is the most common DMARD used to treat rheumatoid arthritis. Methotrexate may be used: 1  In the early stages of rheumatoid arthritis to prevent disease progression. 2  In combination with other medicines such as other DMARDs. It can take 3 to 6 weeks to start to feel your methotrexate work. It takes even longer -- 12 weeks -- to get the full effects. Your doctor will test your blood often to check on how well your treatment works and to make sure it’s safe for organs such as your liver. 1 | 2. You will take 7.5 to 10 milligrams each week. Your doctor may raise that to 20-25 milligrams per week if needed. The pills will come with directions about how many to take and when. If you’re not sure about those instructions, ask your doctor or a pharmacist. Hi Gemz10. I think most people would say 12 weeks as this is when they would up the dose of your treatment if you need it. I have been on Methotrexate for about 18 mnths and when diagnosed I have minimal syptoms, mainly the balls of my feet, stiff fingers, and really really really really tired! I was diagnosed with RA in october and have been taking methotrexate for 13 weeks now. I still have inflamation and sometimes pain/discomfort walking. You can take methotrexate in either pills or shots. There are prefilled methotrexate shots that are easy to take at home. You will take 7.5 to 10 milligrams each week. Your doctor may raise that to 20-25 milligrams per week if needed. The pills will come with directions about how many to take and when. If you’re not sure about those instructions, ask your doctor or a pharmacist. If your doctor prescribes methotrexate, it is important to be monitored regularly, both for the effectiveness of the drug on your psoriatic arthritis and also for potential adverse effects on the blood cells and liver. For active psoriasis, the typical dose is 10 to 25 mg per week, not to exceed 30 mg per week. For psoriatic arthritis, the dose is typically 7.5 mg to 2
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0011139/?report=details http://rheuminfo.com/medications/methotrexate/methotrexate-detailed-information http://www.webmd.com/rheumatoid-arthritis/methotrexate-for-rheumatoid-arthritis http://www.webmd.com/rheumatoid-arthritis/methotrexate-for-rheumatoid-arthritis http://www.webmd.com/rheumatoid-arthritis/methotrexate-treatment-ra http://arthritiscareforum.org.uk/viewtopic.php?f=8&t=21325&view=next http://www.webmd.com/rheumatoid-arthritis/methotrexate-treatment-ra http://www.arthritis.org/about-arthritis/types/psoriatic-arthritis/articles/methotrexate-and-psoriatic-arthritis.php
how long does it take for methotrexate to work for arthritis