Our multidisciplinary geriatric mobile unit works in behalf of the frail elderly people, aged at least 75, who are in loss of self-reliance. One of its main aims is so optimize medical prescriptions. The purpose of this study was to show the benefit of geriatrician and pharmacist interventions over the quality of medical prescriptions for the elderly. Medication reconciliation of treatment and reassessment of the appropriateness of the prescriptions was systematically carried out. The problems related to drug therapy have been listed and classified according to the criteria of pharmaceutical interventions defined by the French Society of Clinical Pharmacy (SFPC). Out of 181 patients, 86,2% had potentially an inappropriate or sub-optimal prescription. Finally, 462 optimizations were proposed (2.9±1.9 by patients): 204 withdrawals, 166 additions, 58 dosage adaptations, 21 therapeutic follow-ups and 13 modalities of administration. This reassessment of the prescriptions allowed to develop between our geriatric mobile unit and the liberal professionals a communication focused on the therapeutic optimization and to spread recommendations on the proper use of drugs in the elderly population.