To evaluate the use of micronutrients (minerals and vitamins) as adjunctive therapies for psychosis when added to conventional medications.

Rural primary care and psychiatry clinic in Northern New England, USA.

People over age 18 diagnosed with a psychotic disorder on medications.

Fifty consecutive clients during one month's time were invited to participate; 19 completed a one-month open-label phase of the addition of a micronutrient to their medication regimen; all 19 then withdrew rather than risk randomization to a placebo. We then compared the response of those 19 over 24 months of micronutrients+medication to the 31 people who declined participation enriched by an additional 28 consecutive patients recruited over the second month of the study for a total of 59 who received medication without micronutrients.

All clients were evaluated with the Positive and Negative Symptom Scale and the Clinical Global Impression scale at study baseline and after 3, 6, 9, 12, 15, 18, and 24 months. Psychosis was confirmed with clinical interview using DSM IV-TR criteria. All participants had normal physical examinations and laboratory studies.

Outcomes were similar for both groups until 15 months, though the micronutrient group used significantly less antipsychotic medication throughout that time (P<0.001). At 15 months, the micronutrients+medication group exhibited significantly fewer symptoms than the medication only group, a difference that was even stronger at 24 months.

Micronutrients may be a beneficial long-term, adjunctive strategy for people with psychotic disorders, allowing for smaller doses of antipsychotic medications.