Written by the UPGUYS Editorial Team
Published on July 11, 2022
In the United States, doctors fill over 2 million lidocaine prescriptions each year. It is one of the most popular anesthetic drugs worldwide.
Lidocaine injections are often used by dentists to numb a tooth before filling a cavity. However, most lidocaine prescriptions are for the topical version of the drug, not the injection.
And, in smaller doses, it's even available over the counter.
You might be wondering if the drug is worth trying, especially to reduce sensation during activities that can cause a "sensory overload"—like sex. Or should you try a similar local anesthetic: benzocaine?
When comparing lidocaine vs. benzocaine, it's important to consider a wide range of factors (including the composition of each drug and the effects you want).
In this article, discover the key differences between these two popular analgesics. Read on to learn:
Lidocaine is a local anesthetic drug. It's classified as an amino amide. Pharmaceutical practitioners also classify it as an antiarrhythmic medication.
Its utility as an anesthetic is what it's most well-known for. Humans feel pain and tactile sensations with our nerve cells.
Nerve cells communicate to the rest of the body—and our minds—about pain and information input by our sense of touch. Like all cells, nerve cells communicate by passing enzymes through channels.
In the case of nerve cells, each nerve cell has dedicated sodium ion channels on its membrane. Nerve cells react to (and communicate about) stimuli—painful or otherwise—through a process called "depolarization."
Depolarization lets external sodium ions flood the channel to transmit the sensory information.
Lidocaine diffuses through tissues into nerve cells. Then, it interacts with hydrogen ions inside the cells and creates a cation, which binds the interior of the sodium channels.
This interaction and binding can take one to four minutes.
This prevents depolarization, keeping out the sodium ions external to the cell. As a result, the nerve cannot transmit information like "pain." Instead, people feel numb in the tissues with affected nerve cells.
Lidocaine's effect typically lasts for about thirty minutes to three hours. Eventually, the cation breaks down, and the nerve cells return to normal.
This article is written for informational purposes only and does not constitute medical advice. The information provided in the articles cannot and should not replace advice from a healthcare professional. Talk to your healthcare provider about any physical or mental health concerns or the risks and benefits of any treatment or medication.
Lidocaine injections are the most common administration route for surgical medical procedures. IV diffusions are also used to alleviate pain in patients with extremely painful infections, like shingles.
But, lidocaine prescriptions for at-home use are not typically for injections. Instead, people use lidocaine at home in the following forms:
Most of these are topical. Lidocaine can be taken orally to treat mouth and throat pain, but it is not safe to ingest in significant quantities.
Like lidocaine, benzocaine is also a local anesthetic. Pharmaceutical professionals classify benzocaine as an "ester."
Like lidocaine, benzocaine prevents nerve cells from transmitting information by preventing depolarization—the action that lets a nerve cell communicate information about stimuli.
Benzocaine binds to the alpha subunit in the nerve cell to prevent depolarization.
Benzocaine and lidocaine take a similar amount of time to work. It also works regardless of the pH of the cell environment, which is useful when the tissue's pH is altered (due to infection).
Like lidocaine, medical professionals may use benzocaine injections to numb tissues during a procedure.
But, benzocaine injections are not available outside a clinical setting. Instead, you might take benzocaine at home in one of these formats:
Most of these options are topical. Do not inhale benzocaine spray or aerosol. Different formulations are used for different sites, and they utilize different concentrations of the drug.
Lidocaine and benzocaine have similar effects on nerve cells. As a result, they both effectively numb tissues and reduce tactile sensation. But their differences matter.
Lidocaine and benzocaine have different chemical structures. Lidocaine is an amino amide, while benzocaine is an ester.
This difference changes how the drugs interact with the liver. Lidocaine is more likely to be used for pain relief long-term (in a hospital setting or a nerve block) because the liver can break the drug down easily.
In contrast, benzocaine is harder for the liver to break down. It is mostly used topically or applied to the gum tissue.
When used as directed, benzocaine is largely safe for the liver. But, at doses necessary for pain management during severe infection, lidocaine is the better option.
An individual who is allergic to one may not be allergic to the other.
There are few direct, head-to-head comparison studies of benzocaine and lidocaine.
However, one study of the analgesic effect of viscous benzocaine compared to a lidocaine-tetracaine mixture on dental patients found lidocaine effectively numbed gum tissues faster than benzocaine.
However, benzocaine spray affects tissues more quickly than lidocaine spray. One study found benzocaine spray numbed a patient's throat in 15-30 seconds.
The duration of the effect varies by concentration and method. Lidocaine sprays typically last for about an hour, while a lidocaine patch—even an over-the-counter patch—may last for 8, 12, or 16 hours.
Benzocaine spray typically lasts 5-15 minutes. However, benzocaine throat lozenges can last up to three hours. This is because lozenges release medication over time.
Similarly, gel benzocaine (like Orajel) can last 20-30 minutes, as the gel lets the medication seep into the gum tissue a bit at a time.
When comparing uses, focus on at-home usage options. Typical prescription or OTC lidocaine uses include:
Typical benzocaine uses are similar but also include more oral options. People typically use benzocaine at home to:
Atypical and Experimental Uses
No clinical trials have tested the efficacy of either anesthetic with the goal of delaying ejaculation or increasing sexual pleasure. However, both medications prevent nerves from "communicating," which reduces sensation.
Preventing nerve communication during the beginning of sex can slow the rest of the body's response to stimulation. As a result, it is possible to slow down the physical-sexual response cycle.
Moreover, if you feel pain or itching during sex, it is possible that anesthetic medication can help you alleviate or "tune out" that pain. This is the result of the meds limiting nerve cell communication in tissues.
People rarely experience side effects with the at-home dosage of lidocaine. However, side effects, while rare, can be serious. Stop using lidocaine if you experience:
It's important to talk to a doctor about the risk of side effects to you, specifically given your medical history.
Both lidocaine and benzocaine interact dangerously with certain medications. For a full list of drug interactions, use the National Library of Medicine's Drug Interaction API.
Benzocaine rarely causes side effects. But, potential benzocaine side effects include:
Over-the-counter benzocaine and lidocaine are typically safe. The main questions to ask yourself when you choose between them are:
Lidocaine lasts much longer than benzocaine. Benzocaine begins numbing faster.
Lidocaine and benzocaine are both effective, relatively safe anesthetic agents. But, they are chemically different. So, if you cannot use one drug due to an allergy or interaction, you may still be able to use the other.
Both benzocaine and lidocaine come in different forms and are applied topically. Both reduce sensation, which can help alleviate itching and pain, and may slow down your physical-sexual response.
Interested in topical anesthetic products tailored to your needs? Talk to a physician about your options today.