Methotrexate is an excellent disease modifying drug for a whole host of rheumatic diseases - especially RA and Psoriatic arthritis / spondyloarthropathy patients, and also may be used in other spondyloarthropathies - including ankylosing spondylitis. It is used weekly. .. starting dose approx. 7.5 - 10 mg WEEKLY. Psoriatics often require more dosage.
The tablet takes 2-3 wks before you notice changes- reduction in swelling and joint counts and less morning stiffness.
If you cannot tolerate the drug orally, it can be given sub-cutaneously via a 26 / 28 guage needle.

It has several potential side effects.

I will list some of the most common here :

1 Nausea- especially when first used. The tabs can be divided up on the day of use to reduce this effect.
2 Mouth ulcers - Interestingly, a therapy for this problem was discussed at the ACR meeting in Orlando - which I have found useful on occasions. Dissolve 300mg of allopurinol in 50ml of water and use this as a mouthwash. Rinse the mouth .Do not swallow.
It is important to exclude leukopenia (low white blood cell count) as a cause of the mouth ulcers.
3 Blood problems from marrow suppression- we therefore watch blood counts before use and then at 2 weeks and then after 1 month and then 2 monthly
4 A potential for a type of liver cirrhosis - or inflammation with damage. This is a cumulative dose effect. And in the old days biopsies were done before using the tablets. It occurred more in high doses with Psoriatic patients and was almost unheard of in RA patients. The biopsy is now no longer done as a routine and we now monitor certain liver tests before use and then at 2 weeks then after 1 month and then 2 monthly
5.A type of pneumonitis - or inflammation of the lung like a pneumonia.
We therefore do a baseline chest X ray
6.. Alopecia - or hair loss
7. It is contraindicated in pregnancy as fetal abnormality is described. Planning of pregnancy is essential, and the methotrexate should be stopped 3 months before conception. This applies also to MALES as well as FEMALES.

The side effects are lessened by addition of FOLIC ACID VITAMIN B 5mg / day.
The side effects are INCREASED by CO-USE of aspirin .

Side effects sound bad - but the disease (RA) is a SERIOUS ONE and the side effects are less than the problems of the disease itself. However only active synovitis will benefit - not the burned out stage -where the disease has already ravaged the joints and left bony changes without active swelling.
The best use of such medications is therefore EARLY ON.
Too late may = MISSED THE BOAT.

Encourage an aggressive approach from your doctors- and especially a SPECIALIST OPINION. One thing is for sure- Such medications require an expert and that means Speak to your RHEUMATOLOGIST, who will know the potential problems and what to expect from these drugs.

More recently - in the past few years - the drug has found a great place in the management of Juvenile Chronic Arthritis (JCA) / Juvenile Rheumatoid arthritis (JRA), although not yet registered for this use by the FDA in USA at this time.

For an update on   methotrexate in RA - go to my methotrexate in RA page