Vimpat side effects Get emergency medical help if you have signs of an allergic reaction to Vimpat: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Seek medical treatment if you have a serious drug reaction that can affect many parts of . Less serious side effects may include: dizziness, spinning sensation; loss of balance or coordination; blurred vision; nausea, vomiting; drowsiness, tired feeling; or; headache. 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 FDA . The most common side effects of VIMPAT include: dizziness; headache; double vision; nausea; Side effects of VIMPAT in children are similar to those seen in adults. These are not all of the possible side effects of VIMPAT. For more information ask your healthcare provider or pharmacist.