Dr. de Rios specializes in the mental health needs of Latino immigrant children, adults and families. She works with drug abusing clients to help them in the rehabilitation process, drawing upon her encyclopedic knowledge of drug use and abuse patterns throughout history.

She conducted anthropological fieldwork on traditional folk healing in the Peruvian Amazon and coast, studying the plant hallucinogen, ayahuasca, in the treatment of emotional and psychological disorders. From l999 to 2005, she directed the qualitative dimension of research in Brazil on the use of ayahuasca among adolescents in the União do Vegetal Church; a recent U. S. Supreme Court decision has allowed the plant hallucinogen to be used as a sacrament in U.S. religious rituals of this church.