Has anyone had any unexplained tiredness while taking methotrexate? I take it for arthritis pain associated with colitis. I also take folic acid which is supposed to lessen the side effects. I take my dosage 5mg Sat morning, 5mg Sat even. and 5mg Sun. morning. I've been taking the med for less than 2 months but I was wondering if it was working. Any comments, advice?