CHICAGO (AP) _ Antipsychotic drugs may control many of the behavioral problems linked to Alzheimer's disease and could help postpone putting victims of the disease in nursing homes, researchers report.

The drugs do not help memory loss associated Alzheimer's, but they significantly improve other symptoms including delusions, suspicion, hallucinations and violence, researchers reported Sunday at a meeting of the American Psychiatric Association.

The drugs, phenothiazine and butyrophenone, have been used in treating the most severe cases of Alzheimer's in nursing homes, but they are not often prescribed for patients with milder symptoms who live at home.

''We're introducing a major new field by addressing treatable behavioral symptoms,'' said Dr. Barry Reisberg, a psychiatrist at the New York University School of Medicine.

''As physicians and researchers, our primary function should be to separate those symptoms that can be treated from those that can't be helped by drug therapy,'' he said at the psychiatric group's annual meeting.

''Institutionalization can be postponed if appropriate therapy is used to suppress these behavioral disturbances,'' Reisberg said.

Alzheimer's is a progressive, irreversible neurological disorder with an estimated 2.5 million American victims. Most are older than 65, but Alzheimer's can strike people in their 40s and 50s as well.

The disease causes about 150,000 deaths a year. No cause or cure is known.

Nursing home care costs an average of at least $20,000 per year for Alzheimer's victims.