When SJW stops working, most people try to take more of it. Instead of 900mg standardized to 0.3% hypericin, they take 1200mg, or 1500mg, or 1800mg, or maybe even more. You might get some short-term relief, but I bet things don't stay that way for long. Frustrated, and now taking double the recommended dose, maybe you end up stopping the SJW and try something else altogether. You conclude that SJW just isn't working for you anymore. What a mistake.
If you've been taking SJW for a long time, let me give you some advice. I took SJW for about eight years, with a few breaks in-between. And I, too, tried increasing the dosage when it stopped working for me, without much avail. It might sound counter-intuitive, but you should probably start taking less rather than more.
Trust me on this one. If it's been at least six months (or maybe several years) and SJW was working fine up to this point, you should now reduce your dosage. Slowly. Don't take more! If you're taking three capsules/day, reduce it to 2/day and leave it that way for several weeks. Odds are you'll feel better, not worse. If you're taking 2/day, drop down to 1/day and see how you feel.
There is some evidence that SJW builds up in your body. That might be why taking less can make you feel better than taking more. Maybe you just need less. Maybe you've recovered, at least partially?? And don't forget, the goal of taking any antidepressant is always to get off it one day! So this is a very good approach, all around. The only problem is really with yourself: when you start to feel more depressed and you're already taking an anti-depressant, most people start taking more. Let my experience and those of others on this website be your guide for long term success... if it's been 6+ months, up to several years and SJW has "pooped out," it's time to slowly get off it altogether. Welcome to the "real" world, without antidepressants - congratulations.