What are the side effects of codeine?

What are the possible side effects of codeine ()? Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.Seek emergency medical attention if a child taking this medication has any of the following life-threatening side effects: noisy breathing, sighing, slow breathing with long pauses between breaths; being unusually sleepy or hard to wake up; blue colored lips.Call your doctor at once if you have a serious side effect such as:
  • slow heart rate, weak pulse, fainting, shallow breathing;
  • feeling like you might pass out;
  • confusion, agitation, hallucinations, unusual thoughts or behavior;
  • feelings of extreme happiness or sadness;
  • seizure (convulsions); or
  • problems with urination.
Less serious side effects include:
  • feeling dizzy or drowsy;
  • nausea, vomiting, stomach pain;
  • constipation;
  • sweating; or
  • mild itching or rash.
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.

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