Sleep is abnormal. The response to some medications is bizarre. When injected intravenously, the medication procaine normally causes drowsiness, but a borderline will feel the 'dysphoria' described in the first paragraph. Borderlines likely have abnormalities with the neurotransmitter 'serotonin' - an incredibly important brain chemical. Serotonin problems can cause anxiety, depression, mood disorders, improper pain perception, aggressiveness, alcoholism, eating disorders and impulsivity.
Excess serotonin can depress behavior.
Serotonin deficiencies can cause many problems, especially suicidal behavior. Low levels of serotonin increase the risk of self-destructive or impulsive actions during a crisis. Due to new developments in medicine, borderlines can now be treated and often cured. It is, in my opinion, as big a breakthrough for borderlines as insulin was for diabetics. Borderlines generally see themselves very profanely.