Thoughts loops are neither inherently bad nor scary, if you are in a comfortable environment and properly prepared for them. They are a part of the trip that should be celebrated, not avoided. Honestly, I think that having a thought loop experience gives one insight into the workings of the human mind in a way that no one who hasn't had such an experience could ever possibly grasp, similarly to seeing psychedelic visuals or having an out-of-body experience for the first time. Coming out of a thought loop, especially the first one ever, is often a mind-blowing experience that you will remember for a very long time. What you really want to do is just not trip somewhere where you can't be completely and utterly open and uninhibited; if you
are in a place where you can totally be yourself with no responsibilities or anxieties, your chances of having a bad time on LSD are slim to none, unless you've just got
tons of demons repressed inside of you. Always keep that in mind when planning your trips and you should be fine.
One thing I should say though, is be careful about giving yourself access to potentially dangerous drugs if you're also tripping! As in, overdosing from continuously redosing when you don't really need it while looping would not be a good thing. o.o A friend of mine actually on his first ever loop, on LSD, was shifting between going to the bathroom, smoking half a cigarette, and then putting out two lines of coke and railing just one of them. He didn't actually realize that he was looping at all until he came out of the bathroom to find like five or six half cigarettes in the ashtray and five or six lines of coke just out on the table, and by then he was having the speediest and a little later on most paranoid trip of his life. And thankfully it was something as short-acting as coke, so some of it was probably wearing off even by the time he got out of the loop; imagine if it had been meth! So, it is important to note that looping can present a genuine danger if you have access to something which you can use to cause yourself harm if you do it repeatedly without noticing, and so such things should be completely removed from the environment before you dose. However, this kind of precaution should be taken before
any trip, and for more reasons than just looping!
For a positive loop example, I'll tell you about one time I (somewhat recklessly) took six hits of LSD along with someone who was taking two hits for their first time with it. I was fairly experienced with it by then, and looping does definitely get less frequent or intense with experience at least with low to moderate doses, but since I was also on a fairly high dose, those psychological effects could still get pretty strong. We started out tripping at a friend's apartment, but he started feeling a little overwhelmed, so we stepped outside for a minute and then decided to head back to his dorm room to chill instead. However, we hadn't actually told the guys we were hanging out with that we were leaving, and I was lucid enough to realize that we had probably left very awkwardly as overwhelmed tripping people often do, so we decided to go back and tell them first. However, by the time we got back to the apartment, we had entirely forgotten this goal and thought we were just walking around to chill out. So, we then decided to go back and hang out in his dorm room instead, but on the walk there, we realized that we had never actually told the guys that we were hanging out with that we were leaving, so we went back to tell them. However, by the time we got there we had forgotten this goal again, and decided that we should probably just go back to his dorm room and chill instead rather than hanging out at this apartment. As we were on the way, for literally no more than half a second, I saw a look of confusion in his eyes. Suddenly I stopped walking, looked back at the path we had walked, and said "Waaaaaait a minute...."
I, having experience with these things already, was instantly freed from the delirium at that moment, but my poor friend, who had never experienced anything even remotely like a loop before, could barely comprehend anything I was saying to him as I tried to explain what was going on. Though, this probably wasn't helped by the fact that my explanations would grow increasingly convoluted as time went by, because I was tripping so hard that I could literally see my explanation in the form of a leaf-shaped fractal sprouting off into a hopelessly large number of irrelevant tangents before my eyes.... But, after a multitude of failed attempts to get him to understand, I
did finally get him to solidify in his mind the memory of me saying "I'll explain when you're sober." Which is a good thing, because he still kept asking what was happening anyway sometimes, and my natural response is to start answering... until I started getting all tongue-tied again, and he would say "Oh yeah, when I'm sober!!" However, there did actually come a point during the experience when we were still both tripping pretty hard but he had become lucid enough, and been through the cycle enough, to start to understand the mechanics of a loop, and that's when it got
really fun!
He was appropriately mind-blown by the whole thing, as was I, because I had NEVER heard of two people looping
together. Even when we were both aware of what was going on, we still kept cycling into the same conversations over again, and we got so good at catching it at different points that we felt like we were riding this shared psychological wave together and we were manipulating how developed it would get before finally breaking and dissolving again. It was honestly one of the coolest things I've ever experienced while tripping, and I feel pretty lucky for having been through it. We spent a lot of that experience actually talking about how incredible it would be to ride that wave with a massive crowd of psychonauts....
So yeah, loops are not a bad thing, it all comes down to what you make of them. Just remember what I said about being in a safe and comfortable place and I think you'll find that there is actually quite a bit of good to be found in experiences like loops!