Hi, I'm glad you have gone on the mtx. I've been on it for 17 1/2 years and on high dose for 12 years now. I've taken all 3 forms, pills, inj, and iv. I had most side effects with tablets, less with inj, and once I adapted to the high dose, the iv's. If you go higher on your dose, and are on it for a long term, you may want to look at inj's. The reason being that the liver detox's about 1/2 of what you take in pill form, and only about 20% of what you take with inj's. With iv's you get nearly 100% of the benefit.
Yes, it is very common to get sleepy with mtx. I've slept up to 18 hours at a stretch. The longer you are on it, the less your side effects will be.
As with any immune suppressor, you will be more susceptible to ordinarily mild symptoms easily moving into infections. So, keep your doctor immediately updated if you have a flu, cold, lung problems, or any other issues. Usually a dose of antibiotics will set you right. As with any medication, if you don't improve in a few days, contact your doctor.
Taking folic acid with mtx is important. Mtx and folic acid are only one chemical bond apart. When they are taken together, the folic acid will neutralize the damage to healthy cells from the mtx.
Leucovorin, mentioned previously, can be thought of as a "pumped up" folic acid. This, then, works on even more of the mtx to prevent damage to healthy cells. The reason this is not used with people taking mtx for cancer, is that the risk to healthy cells vs destroying the "wrong" cells is taken as an acceptable risk. Using chemo drugs for autoimmune diseases is a whole different thing, so we need to protect our healthy cells. Stiff muscles and joints are also common post mtx. The reason: the dead inflammatory cells will pool in muscles and joints. Drinking a good amount of water helps to wash these out of the body. [just a little science explanation] I did put a posting down under cytotoxic drugs which goes thru all this.
Early on with mtx I would allow myself 2 days post tx to have chemo reactions. If I didn't need them, they were a bonus back in my week, if I did, then I had them there. Stay rested, take care of yourself, and if you feel a bit queasy, then allow the time to adjust. I hope it gives you the same sort of benefit I have gotten from it.
Sally