I learned that bipolar people lack empathy. is that true?

No: Antisocial personality disorder includes a lack of empathy. Someone could have bi-polar and antisocial personality disorder, but they don't go together as a rule. Sometimes people with bipolar have episodes where they don't seem to have any empathy but it usually comes back. Bi-polar can be treated, so if you or someone you know has it, be sure to seek help. Best wishes.

Empathy: No, it is not true. Bipolar people, in the middle of a crisis, may seem preoccupied but many bipolar people have immense empathy, particularly because they know what it means to suffer. Suffering often opens our hearts to people and situations in ways that we never previously imagined.

Empathy: They might appear that way when in midst of a psychotic episode, but otherwise they are the exact opposite.