No. It's like an Apple and drinks are even made from it. The shell of the seed contains caustic chemicals, though, and has to be handled carefully while processing.
I learned it the hard way... I was in an apprenticeship with a produce broker dealing in nuts, and they had a few in-shell cashew nuts lying in a little bowl. I was welcome to try and taste any nut that was in the office, so I cracked the shell with my teeth only to find there was an oily liquid in between the outer and inner shell. I spit it into a tissue cause it tasted kind of moldy and gross, and only a few seconds later my oral mucosa started burning like hell, literally. The guy showing me around just stared at me in awe and horror these some 5 seconds and told me to rinse the mouth out with cold water, which kind of made it a lot worse, until the boss realized what was going on and advised me to use milk instead. I did that and it helped, but for the next few days, it felt like i had an extreme sunburn in my mouth and throat. Got a nice job there, though...
You can also find it in Nigeria. .if the juice stains your clothes it almost never goes.. That's why our mother's don't like us plucking it when we were younger
"Bless you."