What are the possible side effects of gabapentin (Neurontin)?

Get emergency medical help if you have any of thesesigns of an allergic reaction: hives; fever; swollen glands; painful sores in or around your eyes or mouth; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, depression, or if you feel agitated, hostile, restless, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have a serious side effect such as:

  • increased seizures;
  • fever, swollen glands, body aches, flu symptoms;
  • skin rash, easy bruising or bleeding, severe tingling, numbness, pain, muscle weakness;
  • upper stomach pain, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes);
  • chest pain, irregular heart rhythm, feeling short of breath;
  • confusion, nausea and vomiting, swelling, rapid weight gain, urinating less than usual or not at all;
  • new or worsening cough, fever, trouble breathing; or
  • rapid back and forth movement of your eyes.

Some side effects are more likely in children taking gabapentin.Contact your doctor if the child taking this medication has any of the following side effects:

  • changes in behavior;
  • memory problems;
  • trouble concentrating; or
  • acting restless, hostile, or aggressive.

Less serious side effects may include:

  • dizziness, drowsiness, weakness, tired feeling;
  • nausea, diarrhea, constipation;
  • blurred vision;
  • headache;
  • breast swelling;
  • dry mouth; or
  • loss of balance or coordination.

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.