Baked,
In my opinion, EnzymeDeficient is absolutely right here; it's completely natural for an individual who gives the experience some thought to come to some depressing or disheartening ideation. That's the nature (and beauty) of the drug, and past experiences can appreciably affect subsequent ones by 'seeding' patterns of thought and emotion.
Rhin's point is an important one; it should always be maintained that ones in ultimate control of the experience - one can always terminate the experience with a mild dose of sedative (assuming rational doses of LSD). However, my chimp isn't of the opinion that this should be the first, second, or even third recourse to pursue. Given the characteristic enhancement of the ability to make cognitive/emotional/sensory associations afforded by LSD - why not try to use these effects to one's advantage?
The next time that LSD is ingested, familiar thoughts will likely recur. Therefore, if one wishes to persevere in their pursuit of a psychologically-profitable relationship with the compound - these thoughts will best be anticipated and confronted,
using rather than
avoiding the effects.
My chimp had a decidedly similar preliminary experience with the compound. He decided that the cognitive effects were simply too intriguing to squander on potential anxiety and internalized depressive ideation. He came up with a contingency plan, if such feelings should affect their obnoxious ambiance once again. He ate a stomach-settling meal a few hours prior to ingestion, rich in carbohydrates, along with a fair bit of water. He then enjoyed the onset of the compound. Upon the appearance of those familiar feelings, he began to stretch thoroughly in a particularly gorgeous and invigorating environment (setting matters!) in isolation. He would focus on the physiological and biochemical effects of stretching, imagining the benefits tangibly and visually. He almost immediately experienced a very positive psychological feedback loop. He realized how powerful the compound was at allowing one to become objective to emotional processes, and rationally confront troublesome feelings. His behavior and demeanor changed as well, and he decided to become quite social and engaged in the activity proximal to him - to astonishingly positive reinforcement from those he was exposed to. Once he realized how 'in control' he was, every subsequent psychedelic experience has been entirely enchanting and insightful.
Please forgive the short rant. In sum, my chimp would advocate anticipating these effects and actively engaging them - if they get to be too much, maintain the fact that they can be terminated with a sedative. He feels that there is a significant psychological component to LSD, and that this facet can well be exploited to one's gratification and future contentment. He's just a no-good, fornicating, drug-taking chimp though - so take that with a grain of salt

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