Serious side effects of hydrocodone and acetaminophen combined in one dose include a slowed heart rate and shallow breathing, according to RXList.com. Jaundice, seizures and feelings of confusion or fear are among other reported side effects. The drug can also cause milder side effects such as headaches, constipation and dry mouth. The most frequently reported side effects of the drug are nausea, vomiting, dizziness and feeling sedate, states DailyMed.
Hydrocodone and acetaminophen are prescribed together for relief of pain that is moderate to severe, says RXList.com. Hydrocodone also acts as a cough suppressant. Each dose with the notation 5/325 contains 5 milligrams of hydrocodone and 325 milligrams of acetaminophen, according to DailyMed.
The risk of shallow breath and slow heart rate is highest among patients who are taking high doses of hydrocodone and patients who are unusually sensitive to the drug, according to DailyMed. As a narcotic, hydrocodone carries a risk of addiction and can impair judgement and reaction times. To prevent constipation while taking hydrocodone and acetaminophen, patients can hydrate and eat adequate fiber, states WebMD.
People with a history of liver disease and those who have more than three alcoholic drinks per day may be unable to take hydrocodone and acetaminophen due to a risk of liver damage from acetaminophen, states RXList.com. Overdoses of acetaminophen-containing drugs can be fatal.