I take 12 grams daily (12 grams is the dose studied in the links I gave above). How many tea-/tablespoons this is depends on the brand. The bottle will tell you there is "x" mg per so much powder (usually per 1/4 tsp serving size). I put the powder in a morning smoothie.
I took the capsules for about a week when my health food store was out of the powder. Since I didn't want to swallow 24 of them (they were 500mg each), I opened them up into my smoothie. I have some capsules left over, and if I feel particularly unstable I empty one onto my tongue and swallow it straight (I also take an extra magnesium tablet). This seems to work.
AllyRae, I didn't notice consistent change until, I think, a bit more than a week, but as I said I can take an extra capsule & feel better shortly. So I dunno

Debi, I'm taking 500mg twice daily of the L-tyrosine, and a "B-100" complex twice daily. The B-100 contains 100mg of each component per tablet, which is several
thousand times the RDA of most of them

so I would advise you to Google niacin and pyroxidine toxicity (those are the B's you can OD on), familiarize yourself with the toxicity symptoms as well as the hard numbers and start at a lower dosage. I appear to need huge amounts of B's, either that or I'm not absorbing most of them. I've read that stress ups your need for B's.
I don't know any reason why this program wouldn't be appropriate during pregnancy but it would probably be a good idea to discuss it with a midwife or OB who's knowledgeable on vitamin therapies.
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