Drugs and alcohol can affect each person differently, and so can the withdrawal symptoms. Sometimes the symptoms might be mild enough for an outpatient program while other cases can be extremely dangerous without around-the-clock medical supervision and treatment. Symptoms can start anywhere from six to twelve hours after the last drink while some of the worst effects, such as hallucinations and seizures, can take hold well after 24 hours.   People who already have a history of severe withdrawal symptoms, and particularly those who have experienced delirium tremens before, are among the most susceptible to the dangers of alcohol withdrawal. Likewise, patients who have been struggling with alcohol use disorder for a long while, or who tend to drink very frequently, can be medically vulnerable to withdrawal in a way that makes inpatient detox the safest treatment option. Withdrawal is the body’s first struggle to do without a substance it’s become dependent upon: this phase of recovery is pivotal, and the greatest risk of a relapse is during detoxification.