Analysis of the evidence of efficacy and safety of over-the-counter cough medications registered in Brazil / A análise das evidências de eficácia e segurança de medicamentos da tosse sem prescrição registrados no Brasil

The objective of this study was to analyze the level of evidence regarding the efficacy, effectiveness and safety of over-the-counter (OTC) cough medications registered in Brazil. The National Health Surveillance Agency database was used to identify the drugs. Clinical trials, systematic reviews, meta-analyses, and studies on safety were searched on the Medline baseline, the Cochrane Library and SIETES (System of Essential Information in Therapeutics and Health; database in Spanish). Most drugs (62.5 percent) were sold as a fixed-dose combination of two or more drugs. Randomized clinical trials were found for only three drugs: bromhexine, dextromethorphan and guaifenesin. No clinical trials were found for fixed-dose combinations. Systematic reviews on Cochrane did not report any evidence in favor of or against the effectiveness of cough drugs. Efficacy is also unclear, especially regarding fixed-dose combinations. The evidence for the efficacy of OTC cough medications available in Brazil is poor due to the lack of quality studies. Pharmacovigilance of OTC cough medications should be encouraged.

O objetivo deste trabalho foi analisar o nível de evidências sobre a eficácia, a efetividade e a segurança dos medicamentos para tosse registrados no Brasil. A base de dados da Agência Nacional de Vigilância Sanitária foi empregada para identificar os medicamentos. Os ensaios clínicos, as revisões sistemáticas, as metanálises e os estudos de segurança foram pesquisados no Medline, the Cochrane Library e SIETES (Sistema de Informações Essenciais em Terapêutica e Saúde, base de dados em espanhol). A maioria dos medicamentos (62,5 por cento) eram comercializados como associação em dose fixa com dois ou mais fármacos. Ensaios clínicos randomizados foram encontrados apenas para três fármacos: bromexina, dextrometorfano e guaifenesina; para associações a dose fixa não foram encontrados ensaios clínicos. Revisões sistemáticas publicadas pela Cochrane não encontraram evidências favoráveis ou contrárias à efetividade dos medicamentos para tosse. Essa eficácia não é clara, especialmente a das associações a dose fixa. As evidências sobre a eficácia dos medicamentos para tosse isentos de prescrição disponíveis no mercado brasileiro são fracas, devido à falta de pesquisas de boa qualidade. A farmacovigilância de medicamentos para tosse isentos de prescrição deve ser incentivada.

Evaluation of commercially available antacid tablets.

Antacids are commonly used for the treatment of acid peptic disease. There is a need to study the relative merits of various brands of antacids available commercially. Twenty three brands of antacid tablet preparations were evaluated with regard to their composition, cost, dispersion time, pH, neutralising capacity and time taken for neutralisation. The cost of various tablets ranged from Rs 0.13 to Rs. 1.48 per tablet and the dispersion time from 20 to 90 minutes. The pH of the dispersed tablet solution ranged from 5.7 to 9.5. The neutralising capacity varied between 8 to 169 meq/tablet and the neutralizing time between 20 and 45 minutes. The cost: neutralizing ratio was calculated and ranged from 102 to 9867 x 10(-3) Rs/meq. A scoring system with a maximum score of 12 has been devised. The study provides a guide for choosing a more potent, quick neutralising and low cost antacid preparation.