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Has Anyone Had Issues With Methotrexate & Humari Causing Fever Blisters & Mouth Sores

A myRAteam Member asked a question 💭
Hayes, VA

Three weeks ago started Methotrexate again and I was already on Humari. This weekend I developed a Fever Blister and mouth sores. I am just curious if anyone else has experienced. Possibly Im trying to fight off a virus or something.

Any input would be appreciated.

April 3, 2022
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Answer Summary

Members shared experiences with methotrexate causing mouth sores and fever blisters, with many confirming these are known side effects that... Read more

Members shared experiences with methotrexate causing mouth sores and fever blisters, with many confirming these are known side effects that some experienced regularly while others avoided entirely. The most frequently recommended solution was taking daily folic acid supplements, which several members credited with either preventing or significantly reducing mouth sores, with one member also suggesting switching to regular Crest toothpaste and another recommending L-Lysine for cold sores. A recurring theme was that reactions vary widely between individuals, with some members tolerating methotrexate well after an initial adjustment period while others could not tolerate it at all, emphasizing the importance of discussing persistent side effects with a doctor to find what works best for each person.

A myRAteam Member

I would add some L-Lysine. It's a supplement that you can get at Walmart. Helps with coldsores too.

April 6, 2022
A myRAteam Member

I used to get mouth sores from MTX. A friend suggested increasing daily folic acid and switching to regular ("old-school") Crest toothpaste. No sores - 4 months and counting. Hope you'll find what works for you soon ...

April 5, 2022
A myRAteam Member

I've been on Methotrexate for 10 months. My doc started me on Folic Acid at the same time(like Marjorie). I only had a week of stomach distress but have been okay with the medication.

April 5, 2022
A myRAteam Member

My doc prescribed folic acid for the mouth sores....try loading up on folic acid

April 4, 2022
A myRAteam Member

I was not able to tolerate MTX at. all. Good luck!

April 3, 2022

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