Some moderate and all severe acute attacks: All should be treated in the emergency room or hospital. In addition to oxygen therapy (to achieve 95% oxygen saturation), a rapid-acting β2 agonist should be administered repeatedly, either by MDI with a nebulizer or by a jet nebulizer device. Continuous nebulized dosing is recommended for initial treatment, followed by intermittent dosing (every 4 h) as needed. There is no evidence to support the routine intravenous use of β2 agonists. The combination of β2 agonists and anticholinergics (e.g., ipratropium bromide) has been shown to achieve better bronchodilatory effects and has been shown to reduce hospitalization rates. The bronchodilatory effect of theophylline is weaker than that of short-acting β2 agonists, and side effects are greater and should be used with caution. In patients taking theophylline extended-release preparations on a regular basis, intravenous theophylline should be monitored for theophylline blood levels whenever possible. Systemic glucocorticoids should be used as early as possible for acute exacerbations of moderate to severe asthma, especially in patients with incomplete response to initial treatment with rapid-acting β2 agonists or whose efficacy cannot be maintained, and in patients who still develop acute exacerbations on the basis of oral glucocorticoids. Oral glucocorticosteroids are comparable to intravenous administration in efficacy and have few side effects, and are the preferred route of administration. Recommended use: Prednisolone 30-50 mg or equivalent other hormone, given as a single daily dose. In severe acute attacks or when oral hormone cannot be tolerated, intravenous injection or drip can be used, such as methylprednisolone 80-120mg, or hydrocortisone 200-300mg in divided doses. Dexamethasone is generally not recommended because of its long half-life and strong inhibitory effect on adrenal cortical function. The course of systemic glucocorticosteroids is 5 to 7 days and usually does not require decreasing withdrawal. Sequential therapy of intravenous and oral administration has the potential to reduce hormone dosage and adverse effects. Nebulized inhaled glucocorticoid solutions can reduce the dose of systemic hormones, and when combined with SABA can shorten the length of hospital stay and reduce the recurrence rate. Magnesium preparations are not recommended for routine use and may be used in severe acute attacks (FEV1 25%-30%) or in those who do not respond well to initial therapy.