She has been taking lithium since a long time. She must be suffering from manic depressive psychosis (MDP). MDP is a mental disorder with periods of depression and periods of elevated mood. Sometimes, patients with MDP show psychotic symptoms during mania phase (elevated mood phase). Therefore, anti-psychotic such as risperidone is prescribed to such patients to control psychotic symptoms. The common side effects of risperidone are agitation, anxiety, dizziness, headache, somnolence, orthostatic hypotension, constipation, nausea, vomiting, abdominal pain, blurred vision, rhinitis, rash and allergy, menstrual disorders, extrapyramidal symptoms (rarely). Slurring of words and loss of balance might be due to lithium toxicity. Advice 1. Consult your doctor for review of treatment 2. Take rest for few days 3. Do not stop or alter dose by yourself unless suggested by your doctor 4. Investigation – serum lithium Thanks