<s>[INST] Good evening my son contracted encephalitis in Nov 2000 and is severely disabled. Irionically my best friend s parent collapsed last week at work and to this moment they do not know what is wrong with him. His memory has gone and is experiencing severe dizziness. Anti viral was stopped today as they found no trace of a virus from the results of the lumbar puncture. Due to have an MRI tomorrow. They also reckon from tests that he has been having seizures. Can you help? [/INST] Hello, First, seizure and collapsing can result from a brain disease, a cardiac disease, an inner ear disease and other general conditions. So, your friend should do some investigations such as: fasting blood glucose, Liver and Kidney function tests, ECG, Echo on the heart, and he should go a specialist in ear, nose, and throat to check the inner ear functions.  The psychological causes should not be ignored even if there is a somatic disease. Hope I have answered your query. Let me know if I can assist you further. Take care Chat Doctor.  </s>