Serotonin antagonists (for 5-HT3 receptors), against the feeling of vomiting and loss of appetite
http://www.adcc.sk/web/humanne-lieky/atc-skupiny/a04aa/antagonisty-serotoninu-5ht3.html
(unfortunately, these drugs are subject to prescription and indication restrictions, which is, of course, a great stupidity)
It is also advisable to administer risperidone with psychiatric drugs. It is the strongest serotonin antagonist.
https://en.wikipedia.org/wiki/Risperidone#Pharmacology
http://www.adcc.sk/web/humanne-lieky/ucinna-latka/risperidon-6128.html
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Interestingly, the psychedelic substance 2C-B (and similar substances) has a very roughly similar molecular structure to vitamin B6, which is also partially psychoactive (it can cause vivid dreams).
https://en.wikipedia.org/wiki/2C-B
https://en.wikipedia.org/wiki/Vitamin_B6
It is also interesting that some newly discovered psychedelic substances have a similar structure to amphetamine. Most of these substances should not be addictive. The disadvantage is that they also act more strongly on serotonin receptors, which can constrict blood vessels in the limbs and make breathing difficult. If a person does not overdose, it should not be a serious problem.
https://en.wikipedia.org/wiki/Substituted_amphetamine
https://en.wikipedia.org/wiki/2,5-Dimethoxy-4-bromoamphetamine
https://en.wikipedia.org/wiki/2C-B
Also an interesting substance: Bromo-DragonFLY
https://en.wikipedia.org/wiki/Bromo-DragonFLY
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The following drugs can be used either in the hospital for the treatment of Amanita poisoning, or these drugs can be given before recreational use of Amanita to block the side effects of muscarine.
https://www.adc.sk/databazy/humanne-lieky/atc-skupiny/A03B/alkaloidy-beladony-a-jej-derivaty-jednozlozkove.html (substances atropine, scopolamine also found in deadly nightshade)
http://www.sukl.sk/buxus/generate_page.php?page_id=386&lie_id=20054 (anti-Parkinson's drug Akineton, active ingredient biperiden, unfortunately so far the only one in its group. The principle of operation is antagonism to acetylcholine receptors)