Get emergency medical help if you have signs of an allergic reaction to Nucynta: hives; chest pain, fast heartbeats, difficult 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.
Call your doctor at once if you have:
noisy breathing, sighing, shallow breathing, breathing that stops;
a light-headed feeling, like you might pass out;
agitation, feeling hot;
severe drowsiness or dizziness, confusion, problems with speech or balance;
a seizure;
serotonin syndrome - agitation, hallucinations, fever, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, diarrhea; or
low cortisol levels - nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness.
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 Nucynta side effects may include:
constipation, nausea, vomiting, stomach pain;
headache, feeling tired; or
drowsiness, dizziness.
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.
 Nucynta side effects (more detail)
