Ipratropium and albuterol are both drugs which widen the airways, or bronchi, which aids breathing difficulties. Drugs which act in this way are commonly known as bronchodilators, and there are a number of different types. Albuterol is an example of what is called a beta-adrenergic agonist, which stimulates receptors in bronchial wall muscles causing the respiratory passages to relax and widen. Ipratropium is an anticholinergic drug, which prevents a substance called acetylcholine from binding to receptors in the bronchial wall muscles. Since acetylcholine would normally cause the airways to constrict and produce mucus, the action of ipratropium serves to dilate the respiratory passages and keep them clear.
Beta agonist drugs such as albuterol, also known as salbutamol, are often used in the treatment of asthma. As asthma drugs, they are usually inhaled, which has the advantage that the medication passes directly to the muscles in the respiratory passages, acting more quickly than a tablet, which would have to be absorbed from the gut into the bloodstream before it could have an effect. Using asthma inhalers also reduces side effects, such as a fast heartbeat or shaking, caused by the drugs having effects on receptors in other parts of the body, apart from the airways. Such asthma treatments may be used to prevent attacks as well as treat them.
Although ipratropium and albuterol are different types of drug, and ipratropium is not commonly used to treat asthma, it is also available in an inhalable form, providing similar advantages of rapid action and reduced side effects. An inhaler which combines ipratropium and albuterol is used to treat chronic obstructive pulmonary disease, or COPD. COPD is the name for a group of conditions which includes emphysema and chronic bronchitis. For the treatment of COPD, it is thought that taking a combination of these drugs is more effective than using either of the drugs alone. In more severe forms of COPD, ipratropium and albuterol may be inhaled using what is known as a nebulizer, a device which converts the drugs into a mist which is breathed in through a mask.
While both ipratropium and albuterol cause bronchial muscle relaxation and airway widening, an anticholinergic drug such as ipratropium takes longer to have an effect, and its action is weaker compared with a beta-adrenergic agonist drug like albuterol. For this reason, anticholinergic bronchodilators are not commonly used in the treatment of asthma, where quicker, more powerful airway widening is generally required. In the emergency treatment of severe asthma, before the patient reaches the hospital, both drugs are sometimes administered together.
