The first thing we need to keep in mind when considering early effects of psychedelics is that tryptamines and phenethylamines are bitter, even in trace amounts, and this is because the tongue and digestive system registers them as toxic substances. Yes, toxic. The body is fully aware that an imbalance of monoamines could throw it into potentially lethal chaos, so it has developed a very refined way of keeping toxic monoamines out of your diet: making them taste bitter on your tongue and making you gag when you try to swallow them. To the brain bitter means poison, and the primal urge is to spit it out and not swallow it. This is one reason why ingesting a psychedelic monoamine is accompanied by a bitter-metallic taste and corresponding upheaval in the digestive system. Remember the taste buds connecting to the facial and glossopharyngeal nerves on the back of the tongue and the vagus nerve that controls digestion? The receptors on the ends of these descending nerves are the first line of contact the brain has with the orally ingested psychedelic, and it is wired to recognize suspicious foreign alkaloids and dangerous monoamines by sending the bitter signal to the brain. So this is how the psychedelic trip all begins.
Nausea and knotted stomachs are commonly associated with the first stage of oral psychedelic ingestion, but not always. If the body is busy with other physical activity (like dancing, walking, or hiking) then the digestive unease will not seem as intense, but for some it will always be a problem. In traditional contexts the post ingestion period is usually spent chanting, meditating, singing, dancing, or in some other rhythmic musical exercise like the beating of drums or shaking of rattles. This helps to distract the mind from the stomach and keep the brain focused on the moment. It also helps to set the tone and tempo for the massive neurochemical event to come. The sickness is just the first stage of the journey, and even before it passes the trip may begin to creep in.
Physiologically there are early reactions to the ingestion of psychedelic amines which only seem to increase anxiety, such as an amphetamine-like rise in blood pressure and respiration. The vasoconstrictive effects of many psychedelics may make the limbs feel cold and the joints feel stiff, hence the onset of psychedelic "shivers." Since seratonin plays a very large role in mediating both digestion and blood pressure, these early symptoms clearly indicate that something is messing with the body's serotonergic systems, particularly TA (trace amine) and 5HT (seratonin) receptors in the peripheral nervous system and gut. Toxic response, nausea, high blood pressure, anxiety, increased respiration, shivers... these do not sound like the hallmarks of a fun night out. Indeed, Coming On and waiting to Come On are not pleasant moments, but this is the trial that all psychedelic initiates must go through: no pain, no gain. The simple dropping of LSD seems like nothing compared to the vile bitter brews of wild flora gulped down and chewed with vigor, then held-in against all inner revolt without the complete spewing forth of your guts. This is a significant rite of passage in some cultures, the make-or-break moment of shamanic training. Cleansing and purging is indeed a significant part of the psychedelic process, but we will get to that later in this section and again in the section on psychedelics and medicine.
http://tripzine.com/listing.php?id=pit11
