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Reversing the Effects of 2% Lidocaine

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02861378
Recruitment Status : Completed
First Posted : August 10, 2016
Last Update Posted : October 14, 2016
Information provided by (Responsible Party):
Dalhousie University

Brief Summary:

Dental procedures often require the use of local anesthesia. The effects of the anesthesia usually linger for some time after the dental procedure is completed which can lead to discomfort and occasionally injury from lip/tongue biting. Clinical trials have shown phentolamine mesylate (OraVerse) to be effective at reducing the amount of time to reversal of local anesthesia compared to sham injections. However, no trials have been conducted comparing phentolamine mesylate to a true control injection. Such trials are needed in order to definitively show that it is the phentolamine mesylate itself that is causing the reduction in anesthesia rather than a dilution effect.

The objective of the proposed research is to conduct a pilot-scale randomized clinical trial evaluating the difference in time required to the return of normal soft-tissue sensation and function in participants who had received an inferior alveolar nerve block (using 2% Lidocaine 1:100,000 epinephrine), followed by an injection with either 1) OraVerse (phentolamine mesylate) or 2) sterile physiological water (control).

The study population will comprise dentistry and dental hygiene students of the second year classes at Dalhousie University, Halifax, NS, Canada. This study population has been chosen because these students usually practice dental anesthesia on each other as a part of a course on local anesthesia.

This proposed pilot scale study will be a double-blind controlled trial using parallel groups. As part of their usual anaesthesia course, the dental and dental hygiene students will be practicing their inferior alveolar nerve injections on one another using 2% Lidocaine 1:100,000 epinephrine. Students who decide to participate in the study will be randomly assigned to one of two groups: Group 1 will receive an injection of OraVerse (treatment group), while Group 2 will receive an injection of sterile physiological water (control group). The time required to the return of soft-tissue sensation and function will be assessed using a questionnaire.

Condition or disease Intervention/treatment Phase
Soft Tissue Anaesthesia Drug: Phentolamine mesylate Drug: Water Not Applicable

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 38 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
Official Title: Reversing the Effects of 2% Lidocaine: A Randomized Controlled Trial
Study Start Date : October 2015
Actual Primary Completion Date : March 2016
Actual Study Completion Date : April 2016

Arm Intervention/treatment
Experimental: Phentolamine mesylate
Once anesthesia is confirmed, subjects in the Phentolamine mesylate group will receive 1 injection of 1ml of a solution containing 0.24 mg of phentolamine mesylate in the same site that was previously anaesthetized (not as a part of the study).
Drug: Phentolamine mesylate
Injection of 1ml at lidocaine injection site
Other Name: OraVerse

Placebo Comparator: Water
Once anaesthesia is confined, the subjects in the water group will receive 1 injection of 1 ml of sterile physiological water in the same site that was previously anaesthetized (not as a part of the study).
Drug: Water
Injection of 1ml of physiologic saline water at injection site

Primary Outcome Measures :
  1. Time to return of normal soft tissue sensation and function [ Time Frame: Every 10 minutes, from the injection of reversing agent or placebo until return to normal soft tissue sensation and function (up to 4 hours) ]
    Soft tissue anesthesia will be assessed using the Assessment of Anesthesia questionnaire

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

Students of the Dalhousie University Dental Clinic who are:

  • Age 18 and over
  • Capable of providing informed consent

Exclusion Criteria:

  • Subjects with a medical history that contraindicates the use of epinephrine.
  • Subjects who have taken an opioid or an opioid-like analgesic within 24 hours of the anesthesia session.
  • Pregnant females

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02861378

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Canada, Nova Scotia
Dalhousie University Faculty of Dentistry
Halifax, Nova Scotia, Canada, B3H 4R2
Sponsors and Collaborators
Dalhousie University
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Principal Investigator: Pierre-Luc Michaud, MSc Dalhousie University
Additional Information:
Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Dalhousie University Identifier: NCT02861378    
Other Study ID Numbers: 2015-3515
First Posted: August 10, 2016    Key Record Dates
Last Update Posted: October 14, 2016
Last Verified: October 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: Only in a publication in a dental journal
Keywords provided by Dalhousie University:
anaesthesia, dental
Additional relevant MeSH terms:
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Adrenergic alpha-Antagonists
Adrenergic Antagonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Antihypertensive Agents