This is sad this spring I went to my pcp , and on my chart it says I'm sensitive to magnesium stearate so she gave me a antihistamine with magnesium stearate in it and I had muscle pain so bad I could stand up straight it felt like I had a heavy weight around my neck pulling me down , I called her up and told her she said you must be sensitive to magnesium stearate yes my chart says so , she said oh.I live in a rural community and they no nothing about MG , I have a notebook that I put together about everything I could find about MG and a list of the meds to avoid and the antibiotics that are safe , my husband calls it my bible , I take it to every doctors appointment.

I would have a discussion with your PCP/ NEURO MUSCULAR DOC for advice again notating with MG antihistamines should be taken cautiously.
Review the antihistamines prescribed with the pharmacist who has access to the pharmacy computer which has all the details of medications available , either OTC or prescription medications. The pharmacist can verify what medication has magnesium. You would not believe some of the fillers or inert substances found in a lot of medications which can cause an allergic reaction or be contraindicated.
My brother is a pharmacist and he has been my best network buddy go-to person to check my meds . As long as I can catch him while he is in the pharmacy , he can answer all my questions with a clic of a button.
You can go to your neighborhood pharmacy and request a consultation.
It is a journey to determine what meds you can take safely with your MG diagnosis.
Stay safe and being informed is your SECRET POWER !

I specifically asked my pulmonary specialist because he told me that my bp medicine was causing a severe cough I had last year.
If your neuro or pcp are unavailable ask a pulmonary 🫁 specialist.
Stay hopeful sis 😎

This is one of the first things I learned from this site ,I love this site and the people on it they know so much because they live with MG daily and they have been there❤

I think you should ask your PCP Brinda. I hope you get an answer soon.