The consumption of products of home enteral nutrition financed by the national system of health, has experimented a remarkable increment. The purpose of this present paper is to evaluate the changes during the last four years (1998-2001), the differences between the costs in which a product is checked and the market occupation of each product.Analysing the official social security forms which were dispensed by pharmacies of Madrid, a study was realized attending to type of product, number of units, cost of each and manufactures industries. As these products are covered by the Spanish Defence of Competition, the data related to the costs has been taken individually of each social security form.The increment between november of 1998 and may of 2000 in packings (66.6%) and costs (over 100%). Consumption shared unequally by three manufactures. The average cost increases 25.9%, whereas the utilization of standard products decreases in favor of more specific modified products. The difference between the cost in which a product is checked, depending on the pharmacy which dispenses it, reaches a 120%.The trend of increased consumption in packings maintains stable until the year 2000, slowing down in 2001, whereas the costs maintain this trend to increase. There is a remarkable increment in products in which administration involves a continuous infusion.