I've been doing some comparative trials between 2 different forms of L-methylfolate; calcium salts (Metafolin) and glucosimine salts (Quatrefolic). As I am taking 30mg of injected MeCbl daily, i have an easy way to see my "effective folate levels". The higher the folate the lower the serum half life of MeCbl. Through the years of bi--weekly periodic folate deficiency the visibility of the MeCbl in urine increases and decreases. After I had a liver problem start as a result of an antibiotic, the level of MeCbl in my urine went up which appeared to be due to a lower folate level. Being at 30mg of Metafolin I decided to try a slightly different form, Quatrafolic, a glucosimine salt instead of calcium, said to dissolve faster. I had rapid "neurological brightening" and improvement in mood. That lasted a week and then the MeCbl started showing up more in my urine in the last week and some symptoms increasing. Now I switched back to the equivalent dose of Metafolin and same thing happened, a sudden improvement and decrease of B12 in urine. I don't know how long it will last but it sort of looks like alternating the two forms keeps performance at the best. WHY? What is happening here? I saw a similar effect when comparing Jarrow MeCbl and Enzymatic therapy MeCbl and I ended up using both for years. It sort of looks like differential absorption between the two forms. I will keep trials going to see what is optimal for me and hopefully figure out what is going on. If anybody has some theories I'd like to hear them. Maybe we need to channel Rich.