Hi Kimberly,
Tridural is a sustained release form of Tramadol and should have the same side effects. Tramadol is a narcotic like pain reliever that effects the nerves in the brain to reduce moderate to severe pain. Since it contains acetaminophen watch your intake of over the counter remedies to ensure you're not taking too much acetaminophen.
You can find out more about Tramadol (or Ultram) at
http://www.healthcentral.com/chronic-pain/find-drug-25432-25.html
http://www.drugs.com/tramadol.html