Withdrawal happens when a person stops using or decreases the amount of drugs or alcohol they use. Depending on the drug it will produce unpleasant symptoms that will usually go away when they use that drug or alcohol again. Withdrawal is the way the body has to readjust to living once the drug has exited the system. A hangover is an example of person withdrawals to drugs or alcohol. Basically what is happening in a hangover is the body is excreting the drug or alcohol faster than it can readjust therefore causing unpleasant effects. Withdrawal symptoms always depend on the drug that is taken and can range from vomiting to fever and body aches or lethargy or headaches. If a drug exits the body slowly then the withdrawal symptoms can be milder whereas if a drug or alcohol is exiting the body at a fast rate the withdrawals will have a greater effect. For example, if a person goes out and binge drinks alcohol (drinking it really fast) it will try and exit the body just as fast therefore causing a really bad hangover. However, if a person has the same amount of drinks over a long period of time then the alcohol will exit the body slower giving the body time to readjust gradually, causing less symptoms of withdrawal.