SOME TIME I FEEL LOW MOOD, IM HAVING PROBLEM SLEEPING. Basically folks I was on Methotrexate for about 4 years, one 15mg injection once a week & to be totally honest with you it actually did bugger all for my psoriatic arthritis & the side effects like stomach aches, nausea, fatigue & affecting your immune system were not too severe but not pleasant. I’m 40 and it’s long years since I had acne and even as a teen it wasn’t that bad. My question is has anyone experienced weight gain whilst taking Methotrexate. I’m 23 years old and drinking and work in a bar while i’m studying at University. Im 26, have psoriatic arthrits and ive been taking methotrexate (6 tabs of 2.5 mg) weekly for about a year and a half with no real side effects and no problems in my blood tests. The side effects and their severity can also differ based on dose; I’m on a relatively low dose because that is all that’s required to deal with my symptoms. I do worry about the long term side effects though as it’s harsh stuff.