THC vs. THCa: Key Differences THC is the psychoactive compound in cannabis, responsible for the "high" experienced when consumed. It binds to CB1 receptors in the brain, leading to euphoria, relaxation, and other effects. THCa, on the other hand, is the raw, non-psychoactive precursor to THC. It doesn’t produce a high until it undergoes decarboxylation (exposure to heat), which occurs when cannabis is smoked, vaped, or cooked. While THC is used for recreational and medical purposes, THCa may offer therapeutic benefits like anti-inflammatory and neuroprotective effects without the intoxicating properties of THC.