Smash was an addictive drug which existed during the High Republic Era. It had stimulating effects. It was consumed by being inhaled out of smashbulbs, which were compatible with a wide variety of anatomical gas exchange systems. When run directly into the gas filters of a mask worn by the consumer, the effects of the drug was intensified. Members of Kassav Milliko's Tempest of the Nihil frequently took smash.
Later, during the Imperial Era, Black Sun ran a smash-processing lab on the planet Dantooine. They tweaked the formula to make it more potent and addictive on a wider range of species.