Is bipolar disorder a more extreme form of borderline personality disorder?

No - Different: Bipolar disoder and bpd share some common characteristics, primarily problems with unpredictable mood swings. However, bpd is primarily a problem in terms of how a person views relationships and his/her own place in the world. Bipolar disorder is primarily a problem with the mood. This can cause relationship problems, but the focus in on the mood related problems.

No: Borderline disorder is a personality disorder while bipolar disorder is a mood disorder.

Bipolar/Borderline: Bipolar do is a mood disorder classified as primary diagnosis on axis 1 of our mental disorders manual. Borderline personality is a personality disorder & a separate issue, being placed on axis 2 diagnoses in our manual. The two, however, can coexist in the same individual.

BPD: Bipolar is a mood disorder, while bpd is a personality disorder, although the 2 can be diagnosed in the same person, bipolar as a primary diagnosis on axis 1 , & bpd on axis 2

Bipolar: No. Bipolar disorder boils down to severe mood swings. BPD is all about volcanic emotions, a disturbed sense of self, self-mutilation, impulsivity, thinking of people/things as all good or all bad, and manipulativeness. There are some cursory similarities between the two disorders, but that's all.