About a year ago I started supplementation for improving methylation, primarily focused on MTHFR A1298C (homozygous) to address lifelong depression, mood swings and fatigue. Using Freddd's protocol as a general guide, I've been tinkering with supplements and increasing dosages of MB12 and methylfolate for a while, as well as continuing to educate myself on this forum, but I just can't figure out what factor (or combination) is holding things up for me Many thanks in advance for reading my story. Aside from usual startup reactions (mostly figuring out the fine line between undermethylation and overmethylation), a scary side effect I get episodically is shortness of breath and difficulty taking deep breaths that comes on quite suddenly. I get energy and mood swings throughout the day, too, and these episodes often coincide with just feeling really tired and weak with only occasional palpitations. It usually hits a few hours after taking mb12, methylfolate and a b-complex (I take a couple of others like p5p and vit D) but have tested that it seems to happen with those three.) Adb12 I have been back and forth with at different dosages because it makes my arms very bulky, ha (I am a female). I had more severe episodes when I started methylation on very low dosages (~200-500 mcg mb12, 50-150mcg of methylfolate). I have raised these over many months to 6-8 mg mb12 (sublingual) and 800 mcg methylfolate (split into 400mcg 2x a day). At first I thought methyl trap or donut hole folate sufficiency but I have always taken more mb12 than methylfolate and my b12 current dose is almost 8X more than the methylfolate. I am fairly sure it's not potassium or hypokalemia but I am still testing- I have tried not having any potassium at all and haven't had this happen (occasionally I get twitching or tight muscles at different times than these episodes, which clearly indicates electrolytes. I take 400mg of magnesium every day and my nutraeval results indicated I was a bit HIGH in magnesium). I drink coconut water a few times per week if not almost every day and occasionally have a bit of potassium gluconate, but it's odd that these episodes just happen so suddenly... FYI I have had tests and a chest scan at the doctors and gotten my blood drawn on a day this happened; potassium serum was 4.2. I also wonder if the b-complex I'm on (NatureMade, recommended by Freddd) has too much niacin that is soaking up extra methyl rendering the methylb12 less effective? My blood serum for b12 still tests off the charts even though I've been taking sublinigual mb12 for months, experimenting with two different brands. Nutraeval results indicated that I don't need too much niacin. or actually MB12: 500mcg was recommended, with 800mcg for methylfolate. Can potassium side effects happen this suddenly? I keep researching this but it seems like others have different mostly muscle-focused reactions. Is there something going on with the b12 not doing its job? I do have a MTR defect, too, which indicates more is needed, but shouldn't 8mg be enough? Any insight is greatly appreciated. I really value how much people on this board contribute their stories and further push the conversation for treating these types of diseases and genetic defects holistically.