National drug formularies: lessons from Latin America

Although pharmaceuticals comprise up to 40% of the health care budget in developing countries, the majority of the population does not have access to many of the essential drugs needed to treat prevalent diseases. This situation demands the development of a national formulary of essential drugs for the public sector. The approach used in developing countries is to select drugs of choice for the treatment of prevalent morbidities and avoid therapeutic duplication, unacceptably dangerous drugs, or drugs of unproven efficacy. Drugs are selected based on a review of the prevalent morbidities, health care worker training, patient characteristics, and efficacy/risk information resulting from scientifically sound studies. An added component to the formulary is the inclusion of concise, unbiased prescribing information for each drug selected. A number of product selection guidelines were proven to be effective in establishing and maintaining an essential drug formulary for developing countries. These guidelines include: 1. Selection of drugs with proven efficacy and acceptable risk; 2. Selection of minimum number of drugs needed to treat the prevalent diseases; 3. Inclusion of new products only if they are found to have distinct advantages over products currently in use; 4. Inclusion of combination products only when they provide true benefit over single ingredients; 5. Selection of drugs with clear "drug of choice" indications for prevalent diseases; 6. Evaluation of the administrative and cost impact of products; and 7. Selection of drugs with established high quality.