Mescal Cactus

Get ready everyone, I'm gonna kick your asses!! Gomu Gomu no...

Mescal Cactus (メスカルサボテン, Mesukaru Saboten) is a very small round cactus that causes hallucination. It grows in Sandora Desert. It first appeared in Chapter 162 and Episode 98.

Luffy ate one instead of the Lizard Meat, without thinking twice. After eating it, Luffy felt like he's drowning and nearly attacked his crew. Tony Tony Chopper knows about this and with his quick thinking, he tranquilize Luffy to sleep, which wears the effect out.

Trivia

 * Some species of cactus have a psychoactive chemical held within called Mescaline, the substance causes confusion of the senses (although not true hallucinations), and notably the name of the Mescal Cactus originates from this very chemical.