I have microdosed Iboga TA extract a couple of times - although, thinking about it now, it was only the one time that I was consistent with it, abstained from other substances throughout, and had clear good results retrospectively. Supposedly was about 50% Ibogaine HCl but I wouldn't be surprised if it was a little less than that. Generally I had very good results shaking off a substance induced, or, rather, lack-of-substance induced depression following getting frustrated at the up down cycle of using armodafinil, phenibut, tianeptine, I think kratom occasionally and a bunch of other noots and fairly mild stuff if I'm honest just to remain productive, alert, and somewhat functional. It's not heroin obviously but regardless I found that I just had far less desire to use these substances, ended up quitting them entirely for, I think about a month, and in that time took up a regular exercise schedule, cleaned up my diet, and just felt very positive about life.
I was basically trying to push the envelope a little - actually, to be perfectly honest, initially I was hoping for some acute nootropic effects that I would feel right away as I have read some people experience, however I did not, in fact I felt a bit listless, unfocused, and brain foggy, but this was not too far off my baseline at the time. As I say though I tried to ramp up the dose basically until I could feel the effects getting a little uncomfortable, so I think I dosed something like, 20mg day 1, 40mg day 2, 60mg day 3, 80mg day 4, then maybe 100mg day 5? Or maybe I stuck at 80mg... either way it was a fairly short "cycle" of low ibogaine doses, and while I was on it, honestly, I did not feel all that great but as I say my baseline was pretty lousy at the time. Almost unconsciously I started to feel a lot better though and I remember writing privately about how much more emotionally stable I was feeling.
After about a month I actually resumed using a few of these substances in order to be more productive with work as well as my exercise routine which retrospectively was what got me into trouble in the first place. I used much lower doses this time, they affected me a lot more, in retrospect, but generally things remained good, or a lot better. In retrospect, thinking about it now, this is what got me into trouble in the first place, prioritising these things over my own wellbeing in some sense, so it's probably not surprising that the benefits began to fade. I started using ketamine occasionally again around this time, after maybe 3 or 4 months of generally good feelings and good habits, which was the icing on the cake as far as wiping out any residual noribogaine afterglow.
A lot of this is retrospective and I didn't really realise the obvious correlations with my psychological state and the substances I was imbibing while they were happening but it's fairly painfully clear to look back on. I am fairly washed out from any other substances right now though so I am considering having another go very soon.
More specifically on topic regarding safety, I don't know much about any long term effects as I only ever tried a consistent microdosing regimen - following a period of abstinence from the substances I was trying to avoid, not just during periods of heavier use and the briefest of abstinences, hoping for a quick fix, as I might have tried since, so this seems to be important - once, and for a short time, but I did find that beyond a certain dose I would get uncomfortable respiratory side effects, as in my nose would feel blocked up and my eyes would get very bloodshot, such that I would not feel comfortable going about in the world like this. I think this happened around the 40mg range, I posted a thread about it before but I forget. I don't know if I'm slightly allergic to the root bark or ibogaine itself or what, or if this effect is usually just overlooked because of the apparently strong physical load of a flood dose, which is the more commonly discussed type of usage...
other bits of advice . You really need to be ultra careful with the build up of nirobogain in your system if your doing 2-3g of root a day, several times a week. That's like a flood after 7-8days, as it can be overwhelming and dangerous. Excess can impact QT heart intervals and cause heart arythymia and need medical attention. Ensure you're not on any other a/d including natural ones as well as opiate need even over counter. 
