Effectiveness of Phentolamine Mesylate as a Reversing Agent for Local Anesthesia in Children

July 6, 2025 updated by: Alaa Saad Abourawash Tolba, Cairo University

A Randomized Effectiveness of Phentolamine Mesylate as a Reversing Agent for Local Anesthesia in Decreasing Self- Inflicted Soft Tissue Trauma Following Local Anaesthesia Injection for Dental Procedure in Children: Randomized Clinical Trial

Local anaesthesia is considered one of the most alarming and non-comfortable dental procedures for children. This goes back to the persisting effect of the local anaesthesia after finishing dental procedures. The effect of Local anaesthesia can last from 3 to 5 hours due to the presence of vasoconstrictor. The U.S Food and Drug Administration (FDA approved the use of phentolamine mesylate (Oraverse) in May 2008 to be used as a drug in reversing the numbing effect of Local anaesthesia by decreasing the time needed to restore the normal functions of the mouth

Study Overview

Status

Recruiting

Intervention / Treatment

Detailed Description

Local anesthesia is the most common method for pain control during any dental procedures, but it is also one of the factors that can trigger discomfort and anxiety in children. Local anesthetics are primarily used to reversibly block action potentials that create impulse conduction along neural axons carrying sensory or motor signals. This occurs by blocking voltage-gated sodium channels. A prospective study of 320 children by College et al., (2000), reported soft tissue trauma frequency as 18%, 16%, 13% and 7% in children who are; less than 4, 4-7, 8-11 and more than 12 years old, respectively following inferior alveolar nerve block anesthesia and its numbing effect.

The search for a pharmacologic means of minimizing postoperative soft tissue anesthesia has focused on phentolamine mesylate (PM), where an injectable form has been developed. Following the administration of local anesthetic with vasoconstrictor, a subsequent phentolamine injection into the same location enhances the redistribution of the local anesthetic away from the injection site as it is an alpha-adrenergic blocking agent, explaining the more rapid return of normal intraoral and perioral sensation.

An intra-oral preparation of PM for the reversal of soft tissue anesthesia was approved by the FDA in May 2008, to be used for patients > 6 years of age and weighing > 15 kg. Later, in March 2016, the FDA approved its use in pediatric patients 3 years and older. Dosage form of OraVerse (phentolamine mesylate) is 0.4 mg/1.7 ml solution per cartridge. Its maximum dose is 2 cartridges in adults. The first published placebo-controlled phase two study reported that, in 10- to 58-year-old dental patients, an injection of phentolamine, at a one-to-one ratio at the site of the previous injection of local anesthesia, accelerated median recovery time to normal sensation of the upper and lower lips by 85 minutes.

Study Type

Interventional

Enrollment (Estimated)

100

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • El Manial
      • Cairo, El Manial, Egypt, 11562
        • Recruiting
        • Cairo University
        • Contact:
        • Contact:
        • Principal Investigator:
          • Alaa Saad, Bachelor degree of science
        • Sub-Investigator:
          • Passant Nagi

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

2 years to 4 years (Child)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

Children aged 5-7 years.

  • Patients in need of dental procedures requiring local anaesthesia.
  • Healthy Children without any systemic or mental disorders.
  • Normal lip sensation before administration of LA.
  • Normal paediatric functional assessment battery (pFAB) for smiling, speaking and drinking and absence of drooling.

Exclusion Criteria:

  • Children seeking dental treatment that does not necessitate local anaesthesia.
  • Children who didn't achieve profound numbness requiring additional anaesthesia.
  • Children who lack the ability to distinct the anaesthetised numb side from the non-anaesthetised one.
  • Children who are not willing to participate in the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Supportive Care
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: participants receiving oraverse injection after local anaesthetic administration
participants receive phentolamine mesylate (Oraverse) injection after the completion of their dental procedures with ratio 1:1 to LA in children weighed 30 kg and more while in children less than 30 kg only half of the amount of the cartridge is administrated.
Phentolamine mesylate is a vaso-dilator that was used for treating dermal necrosis and severe hypertension cases since 1952. It is alpha-adrenergic antagonist. Oraverse is supplied in a dose equal to the amount of LA taken in adults and children with weights more than 30 kg. While in children less than 30 kg, it is advised to use only half carpule according the manufacturer's instructions.
Other Names:
  • phentolamine mesylate
No Intervention: participants with no drug after local anaesthetic administration
participants don't receive any reversal agent or placebo after the completion of their dental procedures.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Time to return to normal function
Time Frame: 2 hours
it is the time needed for the soft intraoral tisues e.g lips, tongue to return to their normal functions after local anaesthesia
2 hours

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of self-inflicted soft tissue trauma
Time Frame: 2 hours
we observe clinical signs of redness, swelling, hematoma or ulcers due to lip biting at dismal of each participant
2 hours
Cost effectiveness of oraverse
Time Frame: Through the completion of the study, with average 1 year
we measure the cost effectiveness of the intervention drug through Incremental cost-effectiveness ratio (ICER) ICER=(C1-C0)/ (E1-E0) C1= cost of intervention drug C0= cost of control E1= effect of intervention drug E0= effect of control
Through the completion of the study, with average 1 year
post-operative pain by 170 mm Heft-parker visual analogue scale (VAS)
Time Frame: the following 24 hours

it is 170mm scale from 0 to 170 mm and it represents

  • no pain: corresponds to 0 mm.
  • mild pain: greater than 0 mm and less than or equal to 54 mm and included the description of faint and weak pain.
  • moderate pain: greater than 54 mm and less than 114 mm.
  • severe pain: equal to or greater than 114 mm to 170 mm and includes the description of strong and intense pain
the following 24 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Chair: mahmoud hamdy, professor, main supervisor

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 5, 2025

Primary Completion (Estimated)

April 20, 2026

Study Completion (Estimated)

June 1, 2026

Study Registration Dates

First Submitted

June 29, 2022

First Submitted That Met QC Criteria

July 6, 2022

First Posted (Actual)

July 7, 2022

Study Record Updates

Last Update Posted (Actual)

July 10, 2025

Last Update Submitted That Met QC Criteria

July 6, 2025

Last Verified

July 1, 2025

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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