hi Gez,
I am on Neurontin and have been for the last several months. I have to take it for my leg, so that I can walk. I take 600 mg. 3x per day.
The only thing that happens when I don't take mine on time is extreme leg/back pain which prevents me from moving/walking.
I have had zero side effects from it. I'm sorry about your friend. How much is he taking?
Mary Alice