A complete plan is necessary that involves medicine, therapy and social support. No treatment plan cures the illness, but does help in providing long-term stability and well-being.
Bipolar medication
Medicines, or drugs, for bipolar tend to fall into two categories: medication for mania, and medication for depression. Other drugs may be prescribed to handle co-morbid problems such as attention deficit disorder, which is common among bipolar people.
Drugs that treat mania are called "mood stabilizers." These are critical, because without an effective mood stabilizer, the person is at risk of entering a manic phase, which then typically causes a subsequent depression, and the cycle continues.
Manic phases have unique dangers associated with them, such as the rapid accumulation of debt, job loss, loss of friends and social support, and generally all the dangers associated with reckless behavior such as car accidents, drug overdose, arrest, and so on.
Drugs that treat depression are called anti-depressants. These are also important because of the debilitating effects of depression. Bipolar people who are not medicated are at risk of suicide.
However, unlike people in the general population, it is dangerous for someone with bipolar to take only anti-depressants, with no mood stabilizer. This is because anti-depressants can cause mania and what is known as "rapid-rapid cycling", where the person goes from depression to mania and back again over a period of days, or sometimes even less.
Anti-depressants can play havoc with the neuro-chemistry of the brain of a bipolar person. For this reason, they must be accompanied by a mood staibilizer to dampen mania and prevent rapid-rapid cycling.
Therapy
Therapy does have a long term positive effect on bipolar.
Therapy plus medication is better than therapy alone (which is definitely not recommended) or medication alone.
Social support
Social support and stability are important in managing bipolar.
Lack of social support can lead to stress (which puts the person in danger of mania) and loneliness (which puts the person in danger of depression).
For this reason, friends and family of someone with bipolar have an important role to play in managing the illness. Their most important function is simply to provide stability and a positive, nurturing social network.