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The Safe Use of Topical Anesthetics

Dental topical anesthetics are among the most common drugs used in patient care, but their risks and adverse reactions are not always well known; in addition, many practitioners are not well versed in United States Food and Drug Administration (FDA) regulations regarding their use. Many topical anesthetics are formulated in higher concentrations than their injectable counterparts, which increases their toxic potential—especially if the agents are misused. To ensure patient safety, clinicians who apply topical anesthetics should be familiar with safe application techniques, contraindications, and possible adverse reactions.


In the 20% concentration, benzocaine gel is the most commonly used topical anesthetic in dentistry, with an onset time of 30 seconds and duration of 5 minutes to 15 minutes.

Beautiful young woman with braces having dental treatment at dentist's office vlada_maestro / iStock / Getty Images Plus
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The typical onset time for 2% topical lidocaine is 3 minutes to 5 minutes, and its duration is 15 minutes; the MRD for 2% lidocaine is 600 mg in adults and 300 mg in children.

Injection of Lidocaine Medical Ampoule Tashatuvango / iStock / Getty Images Plus
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A combination of three ester topical anesthetics—2% tetracaine, 14% benzocaine, and 2% butamben—is available in gel, spray, and liquid forms.

Brown ampoule close-up on the background of drugs Aleksandr Pevve / iStock / Getty Images Plus
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It is common for dental practices to use compounded topical anesthetics and no safety concerns exist.

Chemical experiment concept. pharmacy. Scientist. Laboratory. metamorworks / iStock / Getty Images Plus
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Products that contain phenylephrine or some type of vasoconstrictor are usually light-sensitive and have a shelf life of approximately how many days?

Shot of shelves stocked with various medicinal products in a pharmacy Rowan Jordan / iStock / Getty Images Plus
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The first FDA-approved drug that provides pulpal anesthesia without requiring injection is a nasal spray formulated with 6 mg tetracaine HCl and 0.1 mg oxymetazoline HCl in each 0.2 ml spray.

Nasal spray bottle mockup isolated on teal background. Vector illustration. Serhii Brovko / iStock / Getty Images Plus
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Contraindications of the nasal spray include which of the following?

Woman using a sterile gauze bandage to stop a nosebleed solidcolours / iStock / Getty Images Plus
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The Safe Use of Topical Anesthetics
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This information is from the article “Managing Pain With Topical Anesthetics” by Tulsi J. Patel, RDH, MHA. To read the article, click here.
1 Comment
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    Melanie V. Taverna MSDH, RDH says

    I appreciated this topic! Thank you for presenting this and the quiz.

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