Used to work in a dispensary, usually summed it up for customers like this: THC makes you high, CBD makes you relaxed, CBN makes you sleepy, CBG makes you giggly and maybe hungry.
There is a ton of information out there about cannabinoids, but the research is not very well established in the US because of the legal status of cannabis. THC and CBD are found in much larger concentrations in the whole cannabis plant than CBN and CBG, so concentrated extractions of the latter two (like a CBG vape, for example) may have different effects than smoking/vaping whole flower that contains them.
Also fun fact, THC-a (a compound found in the plant that becomes THC when heated) degrades into CBN with time and oxidation, which is why old weed makes you sleepy.
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