Yes, an overdose of Ultracet (a combination of tramadol and acetaminophen) can be fatal. Tramadol, an opioid pain medication in Ultracet, can cause respiratory depression, which can lead to death in severe cases. Acetaminophen, when taken in high doses, can cause liver damage and liver failure, which can also be fatal. It is important to take Ultracet only as prescribed and not exceed the recommended dose. If you or someone you know may have taken too much Ultracet, seek medical attention immediately.