Get emergency medical help if you have signs of an allergic reaction to Vicodin: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Opioid medicine can slow or stop your breathing, and death may occur. A person caring for you should give naloxone and/or seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.
In rare cases, acetaminophen may cause a severe skin reaction that can be fatal. This could occur even if you have taken acetaminophen in the past and had no reaction. Stop taking Vicodin and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling. If you have this type of reaction, you should never again take any medicine that contains acetaminophen.
Call your doctor at once if you have:
noisy breathing, sighing, shallow breathing, breathing that stops during sleep;
a light-headed feeling, like you might pass out;
confusion, unusual thoughts or behavior;
seizure (convulsions);
easy bruising or bleeding;
infertility, missed menstrual periods;
impotence, sexual problems, loss of interest in sex;
liver problems - nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
low cortisol levels - nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness; or
high levels of serotonin in the body - agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, diarrhea.
Serious breathing problems may be more likely in older adults and in those who are debilitated or have wasting syndrome or chronic breathing disorders.
Common Vicodin side effects include:
drowsiness, headache;
upset stomach, constipation;
blurred vision; or
dry mouth.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Vicodin side effects (more detail)
