Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
If you have to stop taking lamotrigine because of a serious skin rash, you may not be able to take it again in the future.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, depression, anxiety, 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:
fast, slow, or pounding heartbeats or fluttering in your chest;
chest pain, shortness of breath;
fever, swollen glands, weakness, severe muscle pain;
any skin rash, especially with blistering or peeling;
painful sores in your mouth or around your eyes;
headache, neck stiffness, increased sensitivity to light, nausea, vomiting, confusion, drowsiness;
jaundice (yellowing of the skin or eyes); or
pale skin, cold hands and feet, easy bruising, unusual bleeding.
Common side effects may include:
headache, dizziness;
blurred vision, double vision;
tremor, loss of coordination;
dry mouth, nausea, vomiting, stomach pain, diarrhea;
fever, sore throat, runny nose;
drowsiness, tired feeling;
back pain; or
sleep problems (insomnia).
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.
 Lamotrigine side effects (more detail)
