Lidocaine is one of the most widely used numbing agents in the world, and it shows up in a surprising range of products. You’ll find it in over-the-counter creams and sprays at the drugstore, in the injections dentists use before filling a cavity, in prescription patches for nerve pain, and in numbing creams applied before tattoos and cosmetic procedures. Here’s a breakdown of where lidocaine turns up and what concentrations to expect.
Over-the-Counter Creams, Sprays, and Patches
The most common place people encounter lidocaine is on drugstore shelves. OTC lidocaine products come in nearly every form you can think of: creams, ointments, sprays, gels, lotions, roll-on liquids, medicated pads, and adhesive patches. Brands include LMX 4, LMX 5, Solarcaine Cool Aloe, Topicaine, and Aspercreme with Lidocaine, among many store-brand versions.
OTC concentrations typically range from 4% to 5%. These products are marketed for minor cuts, scrapes, sunburn, insect bites, and general muscle or joint soreness. They work by temporarily blocking the nerve signals in the skin where you apply them, so the area feels numb for a period of time. Most are meant for intact skin only and should not be applied to open wounds or broken skin unless the label specifically says otherwise.
Hemorrhoid and Anorectal Products
Several hemorrhoid creams list lidocaine as their active ingredient, usually at 5%. These anorectal products are designed to numb the sensitive tissue around the rectum and reduce the burning or itching that comes with hemorrhoids. You can find them over the counter alongside more traditional hemorrhoid treatments that use other active ingredients.
Prescription Patches for Nerve Pain
Lidoderm is the best-known prescription lidocaine patch, containing 5% lidocaine in an adhesive that sticks to the skin. Each patch holds 700 mg of lidocaine total, though only about 3% of that actually gets absorbed into your body. The vast majority stays in the patch itself. These are FDA-approved specifically for pain after shingles (post-herpetic neuralgia) and are applied to intact skin for up to 12 hours in a 24-hour period, with a maximum of three patches at a time.
Dental Injections
If you’ve ever had a cavity filled, a tooth pulled, or a root canal, there’s a good chance lidocaine was injected into your gums. Xylocaine Dental is one common brand used for nerve blocks and local infiltration in the mouth. The dentist injects a small amount near the nerve supplying the tooth being worked on, which numbs the area for roughly one to two hours depending on the formulation. Many dental lidocaine injections also contain a small amount of epinephrine, which constricts blood vessels nearby and helps the numbness last longer.
Medical Procedures and Emergency Rooms
Beyond the dentist’s office, injectable lidocaine is a staple in hospitals and clinics. Doctors commonly use it to numb skin before stitching a cut, removing a mole, draining an abscess, or inserting a catheter. It’s also used for regional nerve blocks during minor surgeries. In some cases, lidocaine is given intravenously to treat certain heart rhythm problems, though this is a completely different use from pain relief and only happens in a hospital setting.
Tattoo and Cosmetic Numbing Creams
A growing market of numbing creams targets people getting tattoos, piercings, laser hair removal, microneedling, or cosmetic injections like fillers. These typically contain 5% lidocaine and are applied to the skin 30 to 60 minutes before the procedure, often covered with plastic wrap to help the skin absorb more of the drug. Some products combine lidocaine with a second numbing agent (prilocaine is the most common pairing) to boost the effect. This combination was originally sold under the brand name EMLA cream, which is now available in generic form.
Oral Gels and Viscous Solutions
Lidocaine viscous solution is a prescription liquid used to coat the inside of the mouth or throat to relieve pain from conditions like mouth ulcers, mucositis from chemotherapy, or certain throat procedures. This form deserves special caution. Because it’s applied to mucous membranes, which absorb drugs much more readily than intact skin, the risk of systemic absorption is higher. This is particularly dangerous for infants and young children.
The FDA has issued a specific warning against using lidocaine oral products for teething pain in babies. Even small amounts swallowed or absorbed through the gums can cause seizures, serious brain injury, heart problems, and death in infants. The American Academy of Pediatrics recommends massaging a baby’s gums with a clean finger or offering a firm rubber teething ring instead.
How Lidocaine Works
Regardless of the product, lidocaine does the same thing at the cellular level. Your nerves transmit pain signals using tiny channels that let sodium ions flow into the nerve cell, triggering an electrical impulse. Lidocaine physically enters these channels from the inside and blocks them, preventing the electrical signal from firing. No signal means no pain message reaches your brain. The effect is temporary because the drug eventually diffuses away from the nerve and gets broken down by your body.
This mechanism is why lidocaine works faster on thinner or more sensitive tissue (like mucous membranes in the mouth) and slower on thicker skin (like the back or shoulders). It’s also why damaged or inflamed tissue, which tends to be more acidic, can sometimes make lidocaine less effective.
Safety Considerations Across Products
When used as directed on the label, most topical lidocaine products carry low risk. Only a small fraction of the drug makes it into your bloodstream through intact skin. Problems arise when people apply too much product, cover too large an area, leave it on too long, or apply it to broken skin or mucous membranes where absorption is much higher.
Systemic lidocaine toxicity, while rare from topical use, produces a recognizable set of warning signs. Early symptoms include a metallic taste in your mouth, ringing in the ears, numbness around your lips, confusion, or agitation. In more serious cases, it can cause seizures, dangerously low blood pressure, abnormal heart rhythms, or cardiac arrest. People over 65, infants under 4 months, those with liver or kidney disease, and anyone with pre-existing heart conditions face higher risk.
If you’re using multiple lidocaine-containing products at the same time, or combining a lidocaine product with another local anesthetic, be aware that the effects are additive. The total amount of numbing agent your body absorbs is what matters, not just the amount from any single product.