There are a number of things you can do to relieve muscle spasm. Talk to your doctor about muscle relaxants, such as cyclobenzaprine (Flexeril). Taking the supplement magnesium before you go to bed may also help relieve muscle spasms, although it may not be enough if your spasms are severe. It's always a good idea to speak to your GP before adding new supplements.   However, before you start treating your muscle spasms, you may want to and take a step back. How long have you take methotrexate? Did the muscle spasms start before or after you started this medication? You have them all the time or more right around the time you take methotrexate? Muscle spasms may be a fairly rare side effect of methotrexate. If you think the two are connected, I recommend that you talk to your rheumatologist about your symptoms and the impact they're having on your life. You may be able to treat the spasms with muscle relaxants - it's certainly worth a try. Down the road, if treating the spasms don't result in a manageable level of pain, you may want to talk you rheumatologist about trying another medication.   Good luck! Please keep us posted on what happens?