can u describe how he react ? ... and what happend when it goes worse ?

You know it's a mood disorder, so stop saying "orang gila" or "siao liao". Stop being rude when you know it's a disease which they cannot control. Bipolar is harmless towards others as the person himself/ herself usually does self harm. Please treat them with care and take note of their behavior. It doesn't help at all when friends say they are crazy and avoid them. To have this disorder is not something the person wanted, and it's not contagious. He/ she is already suffering from episodes of manic depression so you don't have to add on these harsh words to make it worse.

Man, and there I thought if people understand this disorder better, they will be more open and accepting. Unfortunately a lot of people are still shallow about mental health.