Local dental anaesthesia and evidential breath testing: the effect of injection of local anaesthetic on lip seal.

The effect of local anaesthetic infiltration on the ability of subjects to provide adequate specimens of breath for analysis using an evidential breath testing device was assessed. The results showed that in ten out of the fourteen cases there was no impairment of the ability to provide the specimens of breath at any time. Within two hours of the administration of a local anaesthetic all subjects were able to provide the requisite samples.