August 29, 2016


OraVerse Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Last reviewed on RxList 6/8/2016

OraVerse (phentolamine mesylate) Injection is an alpha adrenergic blocker used to reverse soft-tissue anesthesia, i.e., anesthesia of the lip and tongue, and the associated functional deficits resulting from an intraoral submucosal injection of a local anesthetic containing a vasoconstrictor. Common side effects of OraVerse include:

  • injection site pain
  • fast or slow heartbeat
  • pain following the procedure
  • headache
  • diarrhea
  • facial swelling
  • increased blood pressure (hypertension)
  • jaw pain
  • mouth pain
  • numbness or tingling
  • itching
  • tenderness
  • abdominal pain and
  • vomiting

The recommended dose of OraVerse is based on the number of cartridges of local anesthetic with vasoconstrictor administered. OraVerse may interact with other drugs. Tell your doctor all medications and supplements you use. During pregnancy, OraVerse should be used only if prescribed. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Our OraVerse (phentolamine mesylate) Injection Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is Prescribing information?

The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.

OraVerse FDA Prescribing Information: Side Effects
(Adverse Reactions)


In clinical trials, the most common adverse reaction with OraVerse that was greater than the control group was injection site pain.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates moved in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Dental patients were administered a dose of either 0.2, 0.4, or 0.8 mg of OraVerse. The majority of adverse reactions were mild and resolved within 48 hours. There were no serious adverse reactions and no discontinuations due to adverse reactions.

Table 1 lists adverse reactions where the frequency was greater than or equal to 3% in any OraVerse dose group was equal to or exceeded that of the control group.

Table 1: Adverse Reactions with Frequency Greater Than or Equal to 3% and Equal to or Exceeding Control

Adverse Event OraVerse   Control
0.2 mg
(N=83) N (%)
0.4 mg
(N=284) N (%)
0.8 mg
(N=51) N (%)
(N=418) N (%)
(N=359) N (%)
Patients with AEs 15(18) 82 (29) 20 (39) 117(28) 96 (27)
  Tachychardia 0 (0) 17 (6) 2 (4) 19 (5) 20 (6)
  Bradychardia 0 (0) 5 (2) 2 (4) 7 (2) 1 (0.3)
  Injection site pain 5 (6) 15 (5) 2 (4) 22 (5) 14 (4)
  Post procedural pain 3 (4) 17 (6) 5 (10) 25 (6) 23 (6)
  Headache 0 (0) 10 (4) 3 (6) 13 (3) 14 (4)

An examination of population subgroups did not reveal a differential adverse reaction incidence on the basis of age, gender, or race. Results from the pain assessments in Study 1 and Study 2, involving mandibular and maxillary procedures, respectively, indicated that the majority of dental patients in both OraVerse and control groups experienced no or mild oral pain, with less than 10% of patients in each group reporting moderate oral pain with a similar distribution between the OraVerse and control groups. No patient experienced severe pain in these studies. Study 4 included 150 pediatric patients between 2-5 years of age who received a dose of either ¼ cartridge (0.1 mg), ½ cartridge (0.2 mg) or 1 cartridge (0.4 mg) of OraVerse or sham injection (placebo). Safety in patients in Study 4 was similar to safety in older patients described above. Post-procedural revealed that oral pain was reported in the OraVerse group with a higher frequency (10.1%) than the placebo group (3.9%). The proportion of patients in the OraVerse and placebo groups was comparable with respect to the highest severity of pain experienced: 30.4% of OraVerse patients and 30% of placebo patients reported no pain; 43.1% of OraVerse patients and 45.0% of placebo patients reported mild pain; 19.0% of OraVerse subjects and 17.5% of placebo patients reported moderate pain; and 15.2% of OraVerse patients and 15.0% of placebo patients reported severe pain..

Adverse Reactions In Clinical Trials

Adverse reactions reported by less than 3% but at least 2 dental patients receiving OraVerse and occurring at a greater incidence than those receiving control, included diarrhea, facial swelling, increased blood pressure/hypertension, injection site reactions, jaw pain, oral pain, paresthesia, pruritus, tenderness, upper abdominal pain and vomiting. The majority of these adverse reactions were mild and resolved within 48 hours. The few reports of paresthesia were mild and transient and resolved during the same time period.

Post Marketing Adverse Reactions Reports From Literature And Other Sources

The following adverse reactions have been identified during post approval parenteral use of phentolamine mesylate. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Acute and prolonged hypotensive episodes and cardiac arrhythmias have been reported w h the use of phentolamine. In addition, weakness, dizziness, flushing, orthostatic hypotension, and nasal stuffiness have occurred.

Read the entire FDA prescribing information for OraVerse (Phentolamine Mesylate Injection)

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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