On monday I took 10mg metafolin and 10mg methylb12. I also take Lithium due to COMT issues. Had a headache and slightly poor sleep. Tuesday night large shortness of breath and palpitations but slept it off. Wednesday the palps where back so I decide it could be donut hole folate defficiency and upped metafolin to 30mg, thought I'd keep taking it till they went away but they never did. That night no shortness of breath but awful sleep and massive headache (methyl sensitivity). So Yesterday I decided to stop the metafolin and last night had extreme shortness of breath, and palpitations, shivering, weakness, etc. Almost went to A and E. I tried taking 2mg folate but it didn't do anything. What caused this? Was it donut hole folate deficiency? Too little B12? If it was donut hole, how do I take enough folate without getting the neurotoxicity from bad COMT and methyl groups? How do I reverse it? Thanks for any help.