to quantify the economic cost of polypharmacy in the elderly. cost study design, made in two first-level medical units. The study was conducted in 131 older adult patients with polypharmacy, chronic degenerative disease and at least one medical visit per year. The sample was calculated using the formula of finite population averages. The cost of polypharmacy was assessed in medical consultation, medicine and pharmacy services. The evaluation of the medical cost included the number of visits per year for the same unit cost, the cost of medicine considered the amount of drug per year for the same unit cost, and the cost of the service pharmacy took into account the number of times the pharmacy occupies the unit cost of the same. The statistical analysis included means, percentages and confidence intervals. in family practice the average annual cost is $1,263.26. In pharmacy the average annual cost is $229.91. The average time drug use is 4.37 months per year (95 % CI = 0.9-7.9), the annual average cost drugs is $708.00. Considering the three dimensions the annual cost of polypharmacy in the elderly is $2,201.17. the cost of polypharmacy is high and represents a significant economic impact.