La nanomédecine ou l’utilisation des nanotechnologies en médecine est en pleine expansion. Nous proposons ici d’en présenter les domaines d’application en psychiatrie. Nous avons réalisé une revue systématique de la littérature et soumis les articles sélectionnés à une analyse qualitative. Les principales applications des nanotechnologies en psychiatrie ainsi retrouvées sont : (i) la pharmacologie. Les nanotransporteurs pourraient augmenter la biodisponibilité et la pharmacocinétique des médicaments, améliorer la sécurité et l’efficacité des traitements psychotropes. Nous en exposons ici quelques exemples et détaillons leurs qualités ; (ii) l’analyse du vivant. Les nanotechnologies pourraient apporter une aide technique à l’imagerie in vivo ou l’analyse de métabolome ; (iii) la modélisation du système nerveux central. Des assemblages de nanoparticules pourraient permettre de mieux comprendre certaines maladies mentales. Si l’usage quotidien de la « nanopsychiatrie » est encore lointain, il nous est apparu fondamental que les psychiatres ne délaissent pas ce domaine de recherche dont les promesses pourraient être décisives dans le champ des maladies mentales, de leur diagnostic, de leur traitement et de leur compréhension.

Nanomedicine is defined as the area using nanotechnology's concepts for the benefit of human beings, their health and well being. The field of nanotechnology opened new unsuspected fields of research a few years ago.

To provide an overview of nanotechnology application areas that could affect care for psychiatric illnesses.

We conducted a systematic review using the PRISMA criteria (preferred reporting items for systematic reviews and meta-analysis). Inclusion criteria were specified in advance: all studies describing the development of nanotechnology in psychiatry. The research paradigm was: “(nanotechnology OR nanoparticles OR nanomedicine) AND (central nervous system)” Articles were identified in three research bases, Medline (1966–present), Web of Science (1975–present) and Cochrane (all articles). The last search was carried out on April 2, 2012. Seventy-six items were included in this qualitative review.

The main applications of nanotechnology in psychiatry are (i) pharmacology. There are two main difficulties in neuropharmacology. Drugs have to pass the blood brain barrier and then to be internalized by targeted cells. Nanoparticles could increase drugs’ bioavailability and pharmacokinetics, especially improving safety and efficacy of psychotropic drugs. Liposomes, nanosomes, nanoparticle polymers, nanobubbles are some examples of this targeted drug delivery. Nanotechnologies could also add new pharmacological properties, like nanohells and dendrimers; (ii) living analysis. Nanotechnology provides technical assistance to in vivo imaging or metabolome analysis; (iii) central nervous system modeling. Research teams have modelized inorganic synapses and mimicked synaptic behavior, essential for further creation of artificial neural systems. Some nanoparticle assemblies present the same small world and free-scale network architecture as cortical neural networks. Nanotechnologies and quantum physics could be used to create models of artificial intelligence and mental illnesses.

Even if nanotechnologies are promising, their safety is still tricky and this must be kept in mind.

We are not about to see a concrete application of nanomedicine in daily psychiatric practice. However, it seems essential that psychiatrists do not forsake this area of research the perspectives of which could be decisive in the field of mental illness.