THC cartridges work by using a vaporizer or vape pen to heat the THC oil inside the cartridge to a temperature where it vaporizes but doesn’t combust. This vapor is then inhaled into the lungs, where the THC is absorbed into the bloodstream. The process is more efficient than smoking, as it avoids the harmful byproducts of combustion, such as tar. Most THC cartridges use a battery-powered vape pen, which has an atomizer that heats the oil inside the cartridge. The user simply inhales through the mouthpiece, activating the atomizer and releasing vapor. THC cartridges are often equipped with a coil that heats up the oil when activated by a button or automatically when the user inhales.