Police use breathalyzers to measure a driver's blood alcohol content after a vehicle stop. If the breathalyzer shows the driver's blood alcohol content to be higher than the legal limit, she may be charged with DUI or DWI -- driving under the influence or driving while intoxicated. Several commonly used prescription drugs have been shown to increase an individual's measured blood alcohol content, even if he has not been drinking alcohol.
Salbutamol, also known as albuterol, is a drug used to attain temporary relief of breathing symptoms associated with asthma or chronic obstructive pulmonary disease. Salbutamol is marketed under the brand names Ventolin, Aerolin, Ventorlin, Asthalin, ProAir and Proventil. Salbutamol was the first such drug to be marketed as an asthma reliever, and it has been very successful since its introduction in 1968. However, it appears that salbutamol may have the ability to cause a false positive reading on an alcohol breathalyzer. In 2002, a Spanish study led by pharmacologist Juan Manuel Ignacio-García at the University of Cádiz found that asthmatic patients who had recently taken salbutamol registered a breathalyzer reading of 0.45mg of alcohol per liter of air. However, the results of the Spanish study are not universally accepted. Writing in the July 1991 issue of the journal "Medicine, Science and The Law", Dr. P.J. Gomm states that when a person with asthma has already been drinking, taking salbutamol does not increase that person's blood alcohol reading on a breathalyzer.
Salmeterol is a beta2-adrenergic receptor agonist -- the drug used in inhalers for treating asthma and chronic obstructive pulmonary disease. In the 2002 Spanish study, patients who had taken salmeterol via an asthma-relieving inhaler blew a reading of 0.44 mg of alcohol per liter of air. This is above the legal threshold for breath alcohol established by several countries: Spanish authorities set the limit at 0.25 mg/l; the British limit is 0.35 mg/l. In most U.S. states, the legal blood alcohol limit is 0.08 percent, which equates to a breath alcohol content of 0.4 mg/l. In a 2010 Breath Alcohol Specificity Report for Indiana University's Center for Studies of Law in Action, Patrick Harding recommends a waiting 20 minutes after administration of an asthma inhaler before a breathalyzer test is taken. Harding states that the asthma medications themselves do not significantly affect breathalyzer readings, but that the propellant used in some asthma inhalers can leave alcohol in the mouth for five minutes after the inhaler is used.
Budesonide is a steroidal asthma treatment that is also used for rhinitis, hay fever, allergies, nasal polyposis and Crohn's disease. Budesonide is marketed in nasal inhaler form as Rhinocort. The oral inhaler form of budesonide is marketed as Pulmicort, Symbicort and Budicort; an oral release capsule used in the treatment of Crohn's is marketed as Entocort. Patients in the Spanish study who had taken a budesonide inhaler gave a breathalyzer reading of 0.32 mg/l one minute later. This shows that budesonide inhalers can also cause a false positive breathalyzer reading that is near the legal blood alcohol limit for several countries. However, the results of the Spanish study have been contradicted elsewhere.