Rheumatoid Arthritis Support Group
Rheumatoid arthritis is a chronic, inflammatory, multisystem, autoimmune disorder. It is a disabling and painful condition which can lead to substantial loss of mobility due to pain and joint destruction. The disease is also systemic in that it often also affects many extra-articular tissues throughout the body including the skin, blood vessels, heart, lungs, and...

Two choices: If it's hardly noticeable to you, ignore it. If it bothers you ask about stopping the MTX. I stopped while on Humira (or maybe Enbrel or Orencia - can't keep track) and I was fine. Now I'm on Zeljanz which works without MTX. There are options.
But, hair growing slowly does not sound like it is related to MTX. It's not hair loss. That's not how it happens. Is your diet rich in protein and B vitamins? You might want to do a google search for slow hair growth but beware of ads for hair products: https://blog.docsapp.in/6-reasons-why-your-hair-is-growing-slowly/
First, some background. There had been a mix up of stellar proportions with the insurance company, or so I thought - far too long to detail here - which resulted in a brief standoff in which one party insisted I did not owe money but the doctor's office insisted they had not been paid. As a result, the doctor's office would not order my next Stelara shot, which was scheduled for August 19. Finally, finally got the whole settled, and went into the doctor's office three days ago to hand over the new embossed card with the details from the drug company that the insurance required; I could not do this over the phone. So I'm at the rheumatologist's getting this crap cleared up, and the bureaucrat to whom I am speaking is very tsk-tsk-y about my having missed an appointment......the appointment which she had told not to show up for, as they would not order my Stelara until they'd received the payment they thought they were owed. (The doctor's office, it was finally determined, was in error.)
Well, I wasn't having any of that, and I pointed out that they were the ones who told me not to come to the scheduled appointment, and that I'd invested eight weeks in phone calls, letters, and notarized paperwork getting the insurance straightened out only to eventually learn that they had some kind of clerical error, and that this was not my fault, and I was already two weeks late for the Stelara shot.
Right about then the rheumatologist herself happened to be within earshot, and let me tell you, she let fly; she was livid, could not believe i'd been told to postpone my next shot until things were resolved, couldn't believe she'd not been told about the error, etc.
And, to my surprise, they have a stash of Stelara in the office at all times, so I could just have my shot right then.
Went through the usual preliminaries, pointing out to the tech that the high blood pressure reading was totally an anomaly, completely reasonable, and we weren't even going to discuss it, and then had the weirdest appointment ever; I was not prepared for it and had not collected my thoughts (I usually have an index card with written questions) and my doctor had not reviewed my chart as I was not actually on the schedule, but we both agreed I needed the shot asap so we went ahead with that.
And fortunately I managed to remember to ask about the hair thinning, explaining that it was minimal, and the issue that had brought up the question was not actual hair loss, not like in clumps, but rather extremely slow hair growth, i.e. n need for a haircut after six months of covid-related salon closures.
She looked at my nails, which show no 'moons' at their base, and said she suspects vitamin-B deficiency, which can be an autoimmune related thing. So I've added an over the counter supplement to the routine, and I'm told not to expect a quick turnaround. But if things have not improved by my next appointment, she'll order specific bloodwork to check the level. (We determined that my diet is rich in B vitamins.)
What a pain in the ass this has been. I do like this doctor, and the medical staff is competent and pleasant, but the clerical staff........UGH.
I had a hair appointment scheduled for April, and it was cancelled. In June , they told me to rebook it. But I liked the look of longer hair. I had long hair my whole life till a few years ago. True, short hair is easier to care for, but I like the feel of long hair. I also saw my mom at the end of June, who was in and out of hospital since Jan for broken pelvis and hips. Her hair grew loads, and she looked so much better in long hair than some bargain basement cut. (She is a multi-millionaire, but cheap!)
I look a lot like her, so I decided to grow my hair long, too. Except she has straight hair and I have lots of waves. Anyway I do like it, and it has grown literally about 6 inches since my last cut in Jan or Feb. maybe I will change my mind and get it cut. I have a good hairdresser! Or maybe I will grow my hair long, if it isn't too thin!