The intensity of cocaine’s euphoric effects depends on how quickly the drug reaches the brain, which depends on the dose and method of abuse. Following smoking or intravenous injection, cocaine reaches the brain in seconds, with a rapid buildup in levels. This results in a rapid-onset, intense euphoric effect known as a “rush.” By contrast, the euphoria caused by snorting cocaine is less intense and does not happen as quickly due to the slower build- up of the drug in the brain. Other effects include increased alertness and excitation, as well as restlessness, irritability, and anxiety. Tolerance to cocaine’s effects develops rapidly, causing users to take higher and higher doses. Taking high doses of cocaine or prolonged use, such as binging, usually causes paranoia. The crash that follows euphoria is characterized by mental and physical exhaustion, sleep, and depression lasting several days. Following the crash, users experience a craving to use cocaine again.