The current place of beta 2-agonists in the management of asthma.

Inhaled beta 2-stimulants are the most effective drugs for acute asthma attacks. This is probably due to the functional antagonism against a large variety of possible asthma mediators. A slight rebound increase of bronchial hyperreactivity 12 to 23 h after stopping regular treatment has been proposed. This finding is not well documented and must be further studied. There is no convincing evidence that tachyphylaxis of clinical importance to the bronchodilating effect occurs in asthmatics receiving normal doses of beta 2-receptor stimulants but cannot be totally excluded. Candidates for regular inhaled beta 2-agonist treatment always have inflammation in their airways and should be given inhaled steroids. Steroids not only seem to reduce airway inflammation and hyperreactivity but they also reverse beta 2-receptor subsensitivity in experimental studies. Patients on purely prophylactic antiasthmatic drugs should be instructed always to carry their beta 2-stimulants inhalers.