How Long Does Novocaine Last?

Novocaine is a marvel of modern dentistry. It’s hard to imagine undergoing a dental procedure without it. But afterward, the numbness seems to take forever to wear off.

A numb lip or face can make it hard to go back to work or school. And good luck if you want to take a swig of your favorite iced beverage! Chances are you’ll end up wearing most of it.

“Fortunately, these effects are only temporary and usually disappear in about two hours,” says dentist Juliette Clark, DMD.

What is novocaine?

Novocaine (also called procain) is a local anesthetic that targets a specific area of your body. It causes numbness in that area but doesn’t put you to sleep. Novocaine works by blocking the nerves that carry pain signals to your brain.

Your dentist may give you novocaine for:

• Fillings.
• Root canals.
• Tooth extractions.
• Oral surgery. (You also receive sedation so you’re relaxed and sleepy during the procedure.)

Dentists have long used local anesthesia to reduce pain during dental procedures. Early types included nitrous oxide, ether and cocaine. In the early 1900s, novocaine emerged as a more effective option.

Since then, newer drugs have largely replaced novocaine, but the name has stuck. “The word ‘novocaine’ is a generic term for various local anesthetics,” clarifies Dr. Clark.

Here’s another way to think of it: If you cut yourself, you might say “I need a bandaid.” But what you really need is an adhesive bandage or, in British English, a “sticking plaster.” In the U.S., it’s common to use the name of the most popular adhesive bandage brand — BandAid®— to describe all adhesive bandages. Novocaine is the same. Not all local anesthetics that dentists use are actually novocaine, but we use that brand name to describe them.

Dentists have several options for local anesthesia, some of which contain epinephrine (adrenaline) to boost their effectiveness. The most common local anesthetics Dr. Clark uses are:

• Articaine with epinephrine.
• Lidocaine with epinephrine.
• Mepivacaine.

What to expect with novocaine

Local anesthesia is administered by a needle.

Needles not your thing? Let us put your mind at ease: Just before the injection, it’s common for the dentist to spread a topical anesthetic on your gum to numb it. You may still feel a slight pinch or some pressure, but the needles are very thin, so it’s usually easier and less painful than, for example, getting a vaccine.

Dentists use different techniques to deliver anesthesia:

• An infiltration technique involves injecting the medicine next to your tooth to block the nerve endings. This approach is generally used for upper teeth.
• For a nerve block, the provider injects medication next to the nerve to stop signals at their source. Blocks are particularly effective for the large nerves in your lower jaw.

The anesthesia takes effect quickly, usually within:

• One to two minutes for infiltration anesthesia.
• Five to 10 minutes for nerve blocks.

Depending on the location of the injection, you may lose feeling in your lips, cheek or face. Cue the drooling and half-smile selfies!

As the medication wears off, the numbness may turn into a tingling sensation. These effects should go away completely within two hours, but you may have some lingering soreness around the injection site.

What can make novocaine wear off quicker or last longer?

How long local anesthesia lasts depends on the:

• Dose: If you need a higher dose or multiple shots to achieve numbness or for an extensive procedure, the anesthesia may take longer to wear off.
• Person: The effects of local anesthesia may vary slightly for each person.
• Type of anesthetic: Remember, not all of the anesthetics that we call novocaine actually are novocaine — again, it’s become a catch-all term for local anesthetics. Products like articaine and lidocaine last for about two hours. Mepivacaine wears off sooner.

“People often ask if there’s anything they can do to make the numbness go away quicker,” says Dr. Clark. “Unfortunately, there isn’t. Because these anesthetics affect a specific area rather than your whole body, you just have to wait for them to leave the tissue.”

Side effects of novocaine

Local anesthesia is very safe, but side effects can occur. A review of published articles on the safety of local anesthetics reported a wide range of possible reactions. Some of novocaine’s more common side effects include:

• Biting your lip, cheek or tongue.
• Confusion.
• Dizziness, sweating or turning pale.
• Headache.
• Irregular or pounding heartbeat (heart palpitations).
• Nausea.
• Rapid heart rate.
• Temporary facial paralysis.

If you look at that list, you’ll quickly notice that a lot of the common side effects of novocaine are also symptoms of anxiety. Especially if you struggle with dental anxiety — there’s a good chance you aren’t reacting to the medication: You’re reacting to being at the dentist.

That said, it’s possible (but rare) to react poorly to novocaine. These reactions vary from mild sensitivity to a more serious allergy or toxicity. Most of the time, any side effects that you experience are mild. They also tend to happen while you’re still in the dentist’s chair. If you feel any symptoms, be sure to let your dentist know right away. They can check you and give you any care you need immediately.

There are multiple different ingredients in most local anesthetics, including epinephrine and preservatives. In the unlikely event that you do have a bad reaction, it may be hard to pinpoint the reason without allergy testing.

Preventing reactions to novocaine

The risk of severe side effects from novocaine use is low according to Dr. Clark. That’s partly because local anesthetics are generally safe and well-tolerated, but it’s also because your dentist considers your medical history when they’re choosing an anesthetic for your procedure.

It’s important to let your dentist know if you’ve ever had a bad reaction to local anesthesia. You should also alert them if you are, or may be, pregnant. You don’t need to avoid dental procedures during pregnancy, but it can influence the dentist’s choice of anesthetic. For example, Dr. Clark prefers to use an anesthetic without epinephrine, such as mepivacaine, on patients who are pregnant.

The bottom (gum)line

Novocaine is a specific brand of local anesthetic sometimes used during dental procedures. While it’s not usually dentists’ first choice anymore—there are newer, better drugs out there — it’s become a catch-all term to describe a wide range of drugs that have the same effect.

Local anesthesia is a safe and effective tool in dentistry. Though the numbness takes a few hours to wear off, novocaine makes treatment immensely easier for you and your dentist.