Ingesting heroin happens in a variety of different ways, including injection, smoking, or inhaling it. Once in the blood, it travels quickly to the brain, binds to opioid receptors, and creates a feeling of euphoria. Injecting, however, results in the most powerful effect, sending users a warm rush of bliss before they go "on the nod"—a state of drowsiness fluctuating in and out of consciousness, yet another one of the heroin side effects.