Teeth grinding is commonly associated with which substance?

Teeth grinding, also known as bruxism, is particularly associated with substances that have stimulant effects on the central nervous system. MDMA, commonly known as ecstasy, is one such stimulant. This substance typically leads to increased energy, enhanced sensory perception, and emotional warmth, but it can also result in muscle tension, including jaw clenching and teeth grinding.

The mechanism behind this can be attributed to the way MDMA affects serotonin levels in the brain, which can lead to increased anxiety and physical tension. As users experience heightened feelings of euphoria and stimulation, the accompanying physical effects may include involuntary movements and bruxism.

Other substances listed, such as heroin and Xanax, primarily act as depressants and are typically not associated with teeth grinding, while alcohol, although it may lead to a range of effects, is less directly linked to bruxism compared to stimulants like MDMA. Thus, MDMA and ecstasy are the substances most commonly connected to teeth grinding.