Of course depending on what drug was being abused the symptoms of withdrawal will vary. For example, those that were abusing prescription stimulants are more likely to experience symptoms like extreme fatigue, sleep-related issues, stomach cramps and nausea, and depression. Those that have been grappling an addiction to opioid narcotics will likely experience symptoms that resemble the symptoms of a severe flu, ranging from gastrointestinal issues to headache, runny nose, body aches, chills, and fever. And finally, those that have been abusing depressants are at the highest risk of serious complications resulting from withdrawal. They can face side effects like seizures and coma if not medically monitored around the clock.