Investigators planned to adopt the N-of-1 trial approach to objectively test the effectiveness of ultra-micronized PEA at an individual level in our older outpatients. 65 years old or older persons referring to the Geriatric Unit of the Fondazione IRCSS Ca' Granda Ospedale Maggiore Policlinico of Milan complaining of noncancer chronic pain of any origin will be eligible. Each trial will be a placebo-controlled randomized crossover trial including two um-PEA (600 mg twice a day) and placebo treatment pairs. Investigators will secondarily meta-analyse the performed N-of-1 trials to obtain an estimate of the average effect of um-PEA compared with placebo using a frequentist and Bayesian approach.