Tuberculosis chemoprophylaxis is a therapeutic measure for the prevention of infection by Mycobacterium tuberculosis or to avoid development of the disease in individuals already infected with it. Isoniazid is the most commonly used therapy; however, the use of rifampicin and pyrazinamide has recently been introduced. The objectives of this study were to review the results of the principal studies evaluating the indications for chemoprophylaxis with isoniazid alone and in association with other drugs, its efficacy in the prevention of tuberculosis with respect to the different risk groups and the alternative regimens available. A systematic revision of the medical literature was carried out with particular emphasis on clinical trials and meta-analyses. Official records were also consulted. Those studies involving randomized clinical trials on the use of isoniazid, rifampicin or pyrazinamide in HIV-positive or negative patients were selected. Isoniazid continues to be effective for the prevention of tuberculosis in populations of both HIV-negative and HIV-positive individuals. The standard dose of 5-15 mg/kg/day has shown similar protection over treatment periods ranging from six to twelve months. The risk of developing hepatitis was less than 1%; however monitoring during treatment is recommended in patients over 35 years of age and in users of alcohol. Studies involving treatment regimens with other forms of medication were inconclusive and new studies would have to be performed to evaluate the efficacy of these regimens in populations at high risk of developing tuberculosis.

Keywords: Tuberculosis. Chemoprophylaxis. Isoniazid.

Objective: To assess prescription patterns for short-acting ß2 agonists (SABAs) and other asthma medications in asthma patients treated by specialists and participating in the SABA use IN Asthma (SABINA) study in Brazil. Methods: This was an observational, cross-sectional study conducted at five sites in different regions of Brazil. The primary endpoints were to record SABA prescriptions and obtain data on over-the-counter (OTC) SABA purchases at the pharmacy. Results: Data on 218 asthma patients were analyzed. Of those 218 patients, 80.3% were prescribed SABAs in addition to their maintenance therapy, with a mean of 11.2 SABA canisters in the previous 12 months. Of those patients, 71.4% were prescribed = 3 canisters and 42.2% were prescribed = 10 canisters. None of the patients were prescribed SABA monotherapy. A total of 14.2% of the patients reported purchasing SABAs OTC at a pharmacy without a prescription. Of those, 48.4% purchased = 3 SABA canisters. A fixed-dose combination of an inhaled corticosteroid and a long-acting ß2 agonist was prescribed to 95.0% of the patients. In the year before the study visit, 45.0% of the patients received at least one course of oral corticosteroid burst treatment. Asthma was well controlled in 43.1% of the patients, partly controlled in 34.9%, and uncontrolled in 22.0%. Patients reported a mean of 1.1 severe asthma exacerbations, with 49.1% experiencing 1 or more severe exacerbations. Conclusions: Overprescription and OTC purchases of SABAs are common in Brazil, possibly leading to the need for courses of oral corticosteroids. The health care community should collaborate to implement evidence-based recommendations and promote health education to improve asthma management in Brazil.

Keywords: Asthma; Brazil; Bronchodilator agents; Prescriptions