That's interesting regarding SJW. It's a less common substituent, hyperforin, that has potential, so it may just be dependent on which extract you have, or it may just not work.
I have noticed incredible differences in two extracts.
The first I tried is a pharma-grade SJW I bought at the local pharmacy which is a WS 5570 extract that also have been used in studies. I found great effects with 300mg and 600mg was the ultimate mood-elevator for me. Now that I think of how well it has worked in the past, I might buy some later today.
The second I tried, due to the firsts high cost, was NOW Foods St John's Wort, 300mg does almost nothing, higher doses gives considerably different effects.
I'd just like to point this out, know which molecule your brand have standardized for. My NOW Foods bottle doesn't even mention Hyperforin, which I believe is more beneficial than Hypericin and this might explain my wide differences in results. To strengthen this theory further, NOW Foods SJW should have the same amount of Hypericin according to the bottle.
Wikipedia - Hyperforin
Some pharmacokinetic data on hyperforin is available for an extract containing 5% hyperforin. Maximal plasma levels (Cmax) in human volunteers were reached 3.5h after administration of an extract containing 14.8 mg hyperforin. Biological half-life (t½) and mean residence time were 9h and 12h respectively with an estimated steady state plasma concentration of 100 ng/mL (approx. 180 nM/L) for 3 doses/d. Linear plasma concentrations were observed within a normal dosage range and no accumulation occurred.
This means that effects likely won't establish until 3.5hrs after ingestion, I've certainly noticed this with the pharma-grade extract.
Wikipedia - Hypericin
Hypericin may inhibit the action of the enzyme dopamine β-hydroxylase, leading to increased dopamine levels, although thus possibly decreasing norepinephrine and epinephrine.
I suspect you generally don't want to mess with the availability of NE, so this is probably a bad thing.
There is also this study:
http://www.ncbi.nlm....pubmed/17254717 ("St. John's wort may diminish methylphenidate's efficacy in treating patients suffering from attention deficit hyperactivity disorder.")
But I don't have access to it, so...
Edited by Tukotih Doji, 05 February 2013 - 11:48 AM.