When someone uses a substance, either regularly or intermittently, they can become physically dependent on the substance. This dependence can cause the individual to experience a range of withdrawal symptoms when they discontinue or significantly decrease their use of the substance. Withdrawal symptoms vary depending on the type of substance used, the duration and dosage of use, and the individual's own biology. Common symptoms include physical discomfort such as headaches, nausea, and fatigue, as well as psychological symptoms such as dysphoria, anxiety, irritability, and depression. In some cases, more severe withdrawal symptoms can occur, including seizures, delirium, and even death in extreme cases. It is important to note that withdrawal symptoms can be prevented and managed through professional medical intervention.