Simran Batra  ( Dow Medical College, DUHS, Karachi )
Rohan Kumar Ochani  ( Dow Medical College, DUHS, Karachi )
Ameema Asad  ( Dow Medical College, DUHS, Karachi )

Madam, Teething gel - a well-known practice to combat teething pain may sound like the perfect solution, but such products are not as secure as they seem. Available readily over the counter, these oral gels contain benzocaine as their active ingredient.¹ Benzocaine is a commonly used ester local anaesthetic to treat conditions such as oral pain due to teething, minor irritation, and sore throat.^1,2 The U.S. Food and Drug Administration (FDA) has warned parents about adverse effects of oral teething medications which contain benzocaine.¹ It has been stated that benzocaine can cause an atypical, but grave, side effect in children of less than 2 years of age, known as Methaemoglobinaemia.^1,3 Symptoms usually appear after the first dose or after several uses of this oral agent. The symptoms are variable and include cyanosis, shortness of breath, tachycardia, confusion, lightheadedness; if not treated, may potentially lead to death.3 Even after warnings issued by FDA in the past decade, benzocaine has not been withdrawn from the market.^1,3 Between the years 2009 and 2017, officials have confirmed one hundred and nineteen cases of benzocaine-induced Methemoglobinemia, resulting in a total of four deaths.¹ Documented evidence against the use of benzocainecontaining products states a case of a 15-month old girl, who was brought to ICU postoperatively, for weaning and extubation after she had undergone surgery and gastrostomy in the past. Her mother ascribed crying to teething which was, in reality, due to futile extubation, and used teething gel for pain relief. Soon after the application of teething gel, the baby de-saturated and responded to oxygen after several hours. This cycle was repeated thrice. After the fourth application, the baby developed profound cyanosis and increased heartbeat. Her laboratory tests showed Methemoglobin of 43% in her arterial blood gases. Finally, after undergoing treatment with Methylthioninium chloride, her symptoms improved immediately.² Such cases have been reported with both liquids as well as gels1. According to the American Academy of Pediatrics, to mitigate a child's teething pain; giving a child teething ring or rubbing his/her gums using mother's finger is effectual. If additional help is needed, paediatricians' after ruling out any other causes, recommend child doses of Acetaminophen or Ibuprofen.⁴ A cross-sectional study in our neighbouring country, India, showed that only 26.3% of the mothers had good knowledge regarding teething⁵ and since teething gels are commonly used in our country, we recommend that an effort must be put into increasing awareness regarding teething gels and its use by local medical institutes.

Disclaimer: None to declare.
Conflict of Interest:None to declare.|
Sources of Funding: None to declare.

References

1. U.S. FOOD & DRUG ADMINISTRATION. Risk of serious and potentially fatal blood disorder prompts FDA action on oral overthe- counter benzocaine products used for teething and mouth pain and prescription local anesthetics. [online] [Cited 2018 Aug 30] Available from: https://www.fda.gov/Drugs/DrugSafety/ucm608265.htm
2. Bong CL, Hilliard J, Seefelder C. Severe methemoglobinemia from topical benzocaine 7.5% use for teething pain in a toddler. Clin Pediatr (Phila) 2009;48:209-11.
3. Taleb M, Ashraf Z, Valavoor S, Tinkel J. Evaluation and management of acquired methemoglobinemia associated with topical benzocaine use. Am J Cardiovasc Drugs. 2013;13: 325-30. doi:10.1007/s40256-013-0027-2.
4. The American Academy of Pediatrics. Teething Pain. [online] [Cited 2018 Aug 30] Available from: h t t p s : / / w w w . h e a l t h y c h i l d r e n . o r g / E n g l i s h / a g e s stages/baby/teething-tooth-care/Pages/Teething-Pain.aspx
5. Fernandes S., Goud R., Potdar S., Pujari S. Teething beliefs and practices among a sub-urban population in India – a crosssectional study. Adv. Hum. Biol. 2013;3:19–25.