What are the side effects of creatine?

What are the possible side effects of creatine ()? Although uncommon, serious side effects have been reported with the use of creatine. Stop taking creatine and seek emergency medical attention or notify your doctor immediately if you experience:
  • an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives); or
  • symptoms of kidney problems such as decreased or little urine.
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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