Both hydrocodone and tramadol are opiate type medications intended for moderate to severe pain. Both can be habit forming if abused but neither should cause addiction in the amounts ordinarily prescribed for pain. Hycrocodone has acetaminophen added to it to increase its potency. You should be careful about taking any other acetaminophen contain medications when taking hydrocodone because too much acetaminophen can cause liver damage. In very rare cases tramadol can cause seizures.

You cannot take alcohol with either and both can cause withdrawl symptoms. With regard to strength and other factors they appear to be quite similar. Check out the below URL's for more information.

http://www.healthcentral.com/chronic-pain/find-drug-25443-25.html

http://www.drugs.com/tramadol.html