Phentolamine mesylate

Although pain control remains the cornerstone of any oral and dental procedure, prolonged local anesthetic effects may be undesirable in many instances in maxillofacial clinical practice. There remains a risk of trauma to the patient’s lips, cheeks and tongue due to this residual effect of the local anesthetic by patients biting on their own tissue or inadvertent burns caused by hot drinks or food which may be consumed. The Food and Drug Administration (FDA) in May 2009 has approved phentolamine mesylate, a nonspecific alpha-adrenergic antagonist, for the reversal of soft tissue anesthesia and the associated functional deficits resulting from a local dental anesthetic. This paper reviews the indications, recommended dosage, mechanism of action, pharmacokinetics, clinical studies, complications and adverse effects of phentolamine mesylate for the reversal of soft-tissue anesthesia resulting from an intraoral sub-mucosal injection of a local anesthetic containing a vasoconstrictor.