Any asthmatic patient at risk of developing exacerbations in severity from mild to very severe and rarely ends in death. Some patients have poor perception of their symptoms and can have a very significant decrease in lung function without a significant change in its manifestations so that with the exception of children under five, it is essential to measure whether the bronchial obstruction by flujometry or spirometry. There are two stages in the progression of an exacerbation of asthma: slow-onset acute asthma or type I, when predominant airway inflammation and patients show clinical and functional deterioration in hours, days and sometimes weeks. This can be between 80 and 90% of exacerbations that occur in adults. The other scenario, less commonly, bronchospasm is caused predominantly by causing an acute exacerbation or type II changes from 3 to 6 hours. In this chapter some recommendations about the treatment of patients in crisis and emphasizes the steps to be taken in different scenarios.