The non-selective beta agonist isoproterenol has been superseded by the highly specific beta2-agonists salbutamol, fenoterol, orciprenaline and terbutaline in the treatment of bronchospasm. Aerosol inhalers provide more rapid relief and usually cause less side effects than tablets. The dose of drug administered by inhaler is approximately one tenth that of the oral form. Patients must be instructed in the correct use of the inhalers. The very young and the elderly may not be able to master the use of inhalers but the increasing availability of rotahalers, spacers and nebulizers should make inhaled drugs more easily administered. Parenteral preparations are used to treat severe asthmatic attacks. Aminophylline by slow i.v. injection remains the drug of choice but much use is made of beta2-agonists (e.g. Terbutaline) which can be given subcutaneously by the nurse, in preference to the more risky, traditional s.c. adrenaline. There is no useful role for combination tablets containing phenobarbitone and no place for sedatives or tranquilizers in treating attacks.
