slu-pp-332 vs 5-amino-1mq is a hot topic right now and for great reason. Personal experience using in 100-400mg range has been absolutely wild along with a handful of clients who have all seen similar 5-Amino-1MQ vs SLU-PP-332: Comparing Two

There are four main types of vitamin B12methylcobalamin, adenosylcobalamin, hydroxocobalamin, and cyanocobalamineach offering unique benefits and varying levels of bioavailability

However, due to its synthetic nature it is also the least bioavailable and active (Hunt, Harrington and Robinson, 2014) Methylcobalamin: The first of our non-synthetic forms of B12 is methylcobalamin, a naturally occurring co-enzyme

The most common are injection-site soreness and brief GI effects from the methionine and choline in the formula

[1] Other rare side effects noted (mostly in older literature or high-dose use) include: polycythemia vera and peripheral vascular thrombosis in patients receiving repeated injections (though these associations are not well understood, they were listed in prior product literature as possible adverse events)