OBJETIVE: To evaluate the effectiveness of providing an educational intervention in primary care (PC) alongside a pharmacological treatment for insomnia. DESIGN: Single blinded non randomised clinical trial. LOCATION: Two urban primary health centers in Gijón (Asturias, Spain). PARTICIPANTS: Patients who consulted for insomnia between July 2012-January 2013 and met the inclusion criteria (n=50) were assigned systematically to the control group (CG) or intervention group (IG). All patients initiated treatment with lorazepam 1mg in the evenings and had four weekly 15 min visits plus a follow-up visit after another month. INTERVENTIONS: The IG received training for control of stimuli, sleep hygiene and respiration and relaxation techniques in the four visits. The CG had only non invasive measures taken. MEASUREMENTS: Considering as cured those who reached a Pittsburgh Sleep Quality Index PSQI <6 or a 50% reduction from baseline level. It was also analyzed the change in the PSQI from baseline to final visit and to follow-up visit, and voluntary interruption of lorazepam. Analysis by Bayesian inference. RESULTS: Twelve out of recoveries after intervention against one out of 24 among control group. Mean change in PSQI to final visit and follow-up visit was: -4.7 (95%CrI:-5.9 to -3.5) and -6,3 (95%ICred: -7.5 to -5.1) in IG; -1.8 (95%ICred: -3 to -0.5) and -1.7 (95%ICred: -2.9 to -0.4) in CG. Interruption of lorazepan: in 4 controls (16,7%) and 9 (34,6%) in IG. Twenty nine patients in GI and 17 in GC completed the trial. Per protocol analysis showed similar results. CONCLUSIONS: The educational intervention in PC improves sleep quality and reduces the need of treatment with benzodiacepines.