April 26, 2017


Side Effects


Clinical Studies Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed 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.

Although no major differences in adverse events between Oraqix and placebo-treated subjects were observed, all patients in the placebo-controlled studies received either Oraqix or a placebo gel (consisting of the vehicle in Oraqix without lidocaine or prilocaine). Therefore, it is not possible to determine if adverse events in each treatment group were attributable to the inactive ingredients comprising the Oraqix or vehicle or if adverse event rates were higher than expected background rates. Therefore, a causal relationship between the reported adverse reactions and Oraqix could neither be established nor ruled out.

Following SRP treatment with Oraqix in 391 patients, the most frequent adverse events were local reactions in the oral cavity (see following table). These events, which occurred in approximately 15% of patients, included pain, soreness, irritation, numbness, vesicles, ulcerations, edema and/or redness in the treated area. Of the 391 patients treated with Oraqix, five developed ulcerative lesions and two developed vesicles of mild to moderate severity near the site of SRP. In addition, ulcerative lesions in or near the treated area were also reported for three out of 168 patients who received placebo. Other symptoms reported in more than one patient were headache, taste perversion, nausea, fatigue, flu, respiratory infection, musculoskeletal pain and accident/injury.

Table 1: Number (percent) of patients with adverse events occurring in more than one patient in any of the treatment groups. Each patient is counted only once per adverse event. The occurrence in a single patient is included in this table if the same symptom has been seen in at least one patient in another group.

System Organ Class Preferred Term Oraqix gel*
(N =391)
n (%)
Placebo gel
(N =168)
n (%)
Lidocaine injection*
(N =170)
n (%)
Muscular-Skeletal System Disorders
Myalgia 1 (0) 2 (1)  
Arthralgia and/or Arthropathy 1 (0) 1 (1)  
Central & Peripheral Nervous System
Headache 8 (2) 3 (2) 5 (3)
Dizziness 1 (0) 1 (1) 1 (1)
Special Senses Other, Disorders
Taste Perversion1 8 (2) 1 (1)  
Gastro-Intestinal System Disorders
Nausea 3 (1) 1 (1)  
Respiratory System
Disorders Respiratory Infection 2 (1) 1 (1)  
Rhinitis 2 (1)    
Body as a whole-General Disorders
Accident and/or Injury 2 (1) 2 (1)  
Fatigue 3 (1) 2 (1)  
Flu?Like Disorder 2 (1)    
Pain (remote from application site) 1 (0) 1 (1) 1 (1)
Application Site Disorders**
Anesthesia Local 2(1)    
Application Site Reaction*** 52 (13) 20 (12)  
1includes complaints of bad or bitter taste lasting for up to 4 hours after administration of Oraqix
* in a cross-over study, 170 subjects received either Oraqix or lidocaine injection 2% in each test period
** i.e. symptoms in the oral cavity
*** includes pain, soreness, irritation, numbness, ulcerations, vesicles, edema, abscess and/or redness in the treated area

Read the Oraqix (lidocaine and prilocaine periodontal gel) Side Effects Center for a complete guide to possible side effects


Other Local Anesthetics or Agents Structurally Related to Local Anesthetics

Oraqix should be used with caution in combination with dental injection anesthesia, other local anesthetics, or agents structurally related to local anesthetics, e.g., Class 1 antiarrhythmics such as tocainide and mexiletine, as the toxic effects of these drugs are likely to be additive and potentially synergistic.

Drugs inducing Methemoglobinemia

Patients taking drugs associated with drug-induced methemoglobinemia such as sulfonamides, acetaminophen, acetanilide, aniline dyes, benzocaine, chloroquine, dapsone, naphthalene, nitrates and nitrites, nitrofurantoin, nitroglycerin, nitroprusside, pamaquine, para-aminosalicylic acid, phenacetin, phenobarbital, phenytoin, primaquine, and quinine are also at greater risk for developing methemoglobinemia [See OVERDOSAGE and WARNINGS AND PRECAUTIONS].

This monograph has been modified to include the generic and brand name in many instances.

Last reviewed on RxList: 3/20/2017

Side Effects

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