It may cause side effects, such as nausea, dizziness, drowsiness, dry mouth and constipation.
An additional note I'd like to add is that as of 2013, the FDA has requested that the amount of Acetaminophen in all of these combination medications be lowered to a maximum of 325mgs, due to the dangers associated with organ damage and overdose toxicity.
Some manufacturers have already begun to implement the change and all others are expected to have done so by January of 2014.
Thus, if it is after that and you are looking for information on this tablet, since the company may retain the imprint, please double check and don't just assume that it still contains 500mgs of Acetaminophen.