Antipsychotic drugs were first developed to treat the delusions and hallucinations of schizophrenia. Since people with Bipolar I disorder may also experience these psychotic symptoms, antipsychotics are also used in bipolar disorder.
Older or "typical" antipsychotics include drugs like haldol (haloperidol), thorazine (chlorpromazine) and Trilafon (perphenazine). Though these drugs have been shown to be effective, they have a high risk of serious side effects such as tardive dyskinesia.
The second generation of antipsychotics are called "atypical" and include Abilify (aripiprazole), Geodon (ziprasidone), Risperdal (risperidone), Seroquel (quetiapine) and Zyprexa (olanzapine). These have a lower risk of causing movement disorders, though these can still occur after prolonged use.
Many of the atypicals, including Seroquel and Abilify, also have positive effects on mood. For this reason, they may be prescribed for people with other conditions including Bipolar II, Cyclothymia, Schizoaffective Disorder and Major Depressive Disorder.
One of the most troubling side effects of most of these medications is weight gain and the potential for triggering diabetes. This isn't necessarily a reason for avoiding a medication that can really help you, but it's a sensible idea to increase your activity level and keep an eye on your diet when you start taking an antipsychotic.