MMDA hydrochloride is primarily used in research settings to study its effects on the central nervous system. It is often investigated for its psychoactive properties, particularly in the context of understanding serotonin receptor interactions and their impact on behavior and perception. Researchers utilize it to explore potential therapeutic applications in mental health disorders, such as depression or anxiety, though it is not approved for clinical use. Additionally, it is sometimes studied for its role in neurochemistry to better comprehend the mechanisms of hallucinogenic compounds. Its use is strictly limited to controlled laboratory environments due to its potent psychoactive effects.