What does a "psychoactive drug" primarily alter?

A psychoactive drug primarily alters mood and consciousness because these substances interact with the brain's chemistry, affecting neurotransmitter systems that regulate emotions, perceptions, and cognitive functions. The primary action of these drugs is to influence how individuals experience their mental state—this includes changes in mood (such as feelings of euphoria, anxiety, or depression) and consciousness (altered awareness, perception of reality, or levels of alertness).

While psychoactive drugs can have secondary effects on physical health, intelligence levels, and memory function, these are not their primary functions. The main focus of psychoactive substances is to modify mental states directly, making mood and consciousness the most relevant effects. This understanding is crucial in substance abuse treatment and prevention, highlighting the significance of psychological rather than purely physical health impacts when discussing drug use and its implications.