FDA Safety Warning about Lidocaine Viscous

On June 25, 2014, the Food and Drug Administration (FDA) released a statement warning consumers and prescribers that prescription oral viscous lidocaine 2% solution should not be used to treat teething pain in infants and young children since it can cause death or serious harm. This warning is based on a review of case reports by the FDA which linked the use of oral viscous lidocaine 2% solution for teething pain to serious adverse reactions such as heart problems, seizures, severe brain injury and death.

As a result, the FDA is warning consumers not to use this product to treat teething pain. In addition, health care providers are advised not to recommend or prescribe it to consumers for teething pain. The FDA is also requiring that a Boxed Warning be added to the drug label, as well as revisions be made to the Warnings and Dosage and Administration sections of the drug label in order to notify consumers of this warning. Additionally, the FDA will also require that additional dosing instructions be included when the drug is prescribed for approved uses.

Furthermore, the FDA advises consumers not to use over-the-counter topical medications to treat teething pain as they can also cause similar harmful effects.

What is Lidocaine?

Lidocaine is a local anesthetic. That is, it causes loss of sensation and pain to the area in which it is applied thus producing a numbing feeling. It acts by reversibly blocking sodium channels which are needed by nerve cells to transmit pain signals to the brain. Therefore, when sodium channels are blocked, the pain signal cannot reach the brain, reducing the feeling of pain.

What is Oral Viscous Lidocaine 2% Solution Used for?

Oral viscous lidocaine 2% solution (Xylocaine Viscous) is FDA-approved to treat pain and soreness due to stomatitis. Stomatitis is inflammation, pain and sores of the mouth, throat and pharynx resulting from cancer chemotherapy, tonsillectomy, upper gastrointestinal tract diseases, and other conditions or procedures. Although this product is not FDA approved to treat teething pain, it has been given to young children. This has lead to overdose or accidental swallowing, resulting in serious health effects and death.

Case Reports Showing Risk of Serious Adverse Effects and Death

The FDA reviewed 22 case reports in which children aged 5 months  up to 3 ½ years of age experienced serious adverse effects and death from using oral viscous lidocaine 2% solution. The case reports included children who were given viscous lidocaine to treat teething pain, some to treat stomatitis, and others who had swallowed the product accidentally. Of the 22 cases, 6 resulted in death, 3 had life-threatening symptoms, 11 needed hospitalizations, and 2 needed medical intervention without hospitalization.

7 out of the 22 cases were due to a reported overdose. This was caused by caregivers’ failure to follow the prescriber’s directions when applying the product or giving more product than what had been instructed.  7 other cases were due to accidental swallowing, and 4 others resulted in an overdose due to a prescribing error. The remaining 4 cases had an unknown cause.

Benzocaine, another local anesthetic commonly used for mouth and teething pain has also been associated with serious adverse effects. In 2011, the FDA released a statement regarding safety issues with use of OTC topical products containing benzocaine. Similarly, this affected infants and children who were given benzocaine to treat teething pain. In this case, the children were 2 years or younger. Benzocaine use was associated with methemoglobinemia, a life-threatening illness that reduces the amount of oxygen carried in blood. Although this illness did not occur frequently, when it did occur, it led to serious illness and resulted in some deaths.  The FDA’s Adverse Event Reporting System (AERS) database identified 21 cases of methemoglobinemia associated with the use of OTC benzocaine gel or liquid products. Of these, 10 cases were life-threatening, 6 were serious and 1 resulted in death.

Since this statement was released in 2011, there have been more than 6 cases of methemoglobinemia reported to the FDA and all 6 cases required hospitalization. Half of these cases were considered life threatening. Alarmingly, all strengths of benzocaine gels and liquids have been associated with methemoglobinemia. Some symptoms of methemoglobinemia include fast heart beat, a feeling of lightheadedness, confusion, fatigue (tiredness), shortness of breath, as well as pale, gray or blue colored skin, lips, and nails. Symptoms may occur when the product is used for the first time or may develop after a while. It may even develop later on with repeated use. Immediate medical attention is required if these symptoms occur.

FDA-Approved Prescription Oral Viscous Lidocaine 2% Solution

Xylocaine Viscous

FDA-Approved Over-The-Counter (OTC*) Benzocaine products

Anbesol Cold Sore Therapy  

* (OTC) means that the product is available over-the-counter and does not require a prescription in order to buy it.

The above list indicates brand names only. Many pharmacies or stores have their own store brand name products which may contain benzocaine. Consumers should consult with their pharmacist or other health care provider if they are not sure whether a product contains benzocaine.

Are there Alternatives to Lidocaine?

At this time, the FDA is not recommending any medications as alternatives to lidocaine. Application of topical medications to gums is not considered useful since they are washed out of the child’s mouth too soon after application to be of any benefit.

What Should Consumers Do?

Consumers should not use prescription oral viscous lidocaine solution to treat teething pain in children due to the serious health risks associated with it. Moreover, the product is not FDA-approved to treat teething pain.

Consumers are also encouraged not to use OTC topical medications for teething pain because some of them may also have harmful effects. If viscous lidocaine solution or benzocaine gels and liquids are kept in the home, they should be stored securely and out of the reach of children to prevent access and accidental swallowing.  

In addition, the FDA recommends that parents and caregivers follow the American Academy of Pediatrics’ Guidelines for treating teething pain. This comprises of using a teething ring that has been chilled in the refrigerator (not frozen). This is because freezing may cause excessive hardening of the teething ring and subsequent damage to the child’s gums. Another recommendation is for the caregiver to gently rub or massage the child’s gums with their finger in order to relieve teething symptoms. 

Consumers should discuss further options or concerns with their health care providers.

Conclusion

The FDA is monitoring reports of adverse effects associated with the use of prescription oral viscous lidocaine and OTC benzocaine to treat teething pain in infants and young children. One issue of great concern is that oral viscous lidocaine solution is still dispensed to infants and young children. For instance in 2012, 4% of all consumers who received dispensed prescriptions in community pharmacies were children younger than 2 years old. 

Consumers should discuss concerns with their health care provider and to report side effects or medication errors to the FDA Med Watch program.

References

American Academy of Pediatrics. Teething: 4 to 7 Months. 

FDA Drug Safety Communication (2011): FDA continues to receive reports of a rare, but serious and potentially fatal adverse effect with the use of benzocaine sprays for medical procedures. 

FDA Safety Announcement (2014): FDA recommends not using lidocaine to treat teething pain and requires new Boxed Warning. 

Lidocaine. In: Clinical Pharmacology. Tampa (FL): Elsevier/Gold Standard. 

Patient information: Mouth sores from cancer treatment (The Basics). In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed July 3, 2014)

Lidocaine (topical): Patient drug information. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed July 3, 2014)