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Novocaine: Uses, side effects and risks

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Medically Reviewed By Colgate Global Scientific Communications


Achieving effective pain control is pivotal when undergoing a dental procedure. Pain relief management  transforms dental procedures from potentially stressful and uncomfortable to smooth and pain-free experiences. Local anaesthetic agents are crucial in enabling dental professionals to conduct interventions without causing pain. One such common local anaesthetic is Novocaine (or novocain). 

What is Novocaine?

Novocaine, also known as procaine hydrochloride, is a local anaesthetic commonly used in dental procedures such as cavity fillings, tooth extractions, and root canals. This common local anaesthetic acts swiftly to numb sensations in the treatment area.

Novocaine typically works very quickly to alleviate pain and its effects generally subside within a short duration. While Novocaine is a safe drug for most individuals, there are some common and uncommon side effects that you should be aware of.

How is Novocaine Used?

A dentist will inject it near the site in the gums to numb that region of the mouth before starting a procedure. The numbing effect makes the pain tolerable. It works by blocking nerve signals that communicate pain sensations while generally allowing other nerve functions to remain intact.

Novocaine is used for the following procedures:

  • Cavity fillings: Injections to numb drilling sites help manage discomfort

  • Wisdom tooth extractions: Anaesthetising the area allows smoother removal

  • Minor dermatological excisions like mole or wart removal: Numbing the skin surrounding the lesion for easier excision

  • Certain ophthalmological interventions including cataract operations: Topical or injected agents prevent sensation during delicate eye procedures

  • Biopsies: Numbed collection sites enable less painful tissue extraction

How Novocaine Works?

Novocaine works by blocking sodium channels on nerve endings near the injection site. This prevents sodium ions from entering the nerve, preventing the nerve signal that registers as pain in the brain. However, it allows some nerve functions like touch to remain.

  • The numbing effect happens when Novocaine attaches to specific sodium channels on the nerve cell membranes. This prevents sodium ions from causing the nerve to depolarize and send pain signals.

  • Meanwhile, other nerve functions like pressure sensations can still be transmitted to the brain.

  • The effect lasts 30-60 minutes as the Novocaine molecules break down and dissipate from the area. The duration and degree of numbness depend on factors like dosage amount and location.

Understanding how Novocaine selectively obstructs pain pathways shows how it can enable procedures like dental surgery without causing discomfort. This pain-blocking mechanism is extremely useful for painful medical and dental procedures, but it also requires extreme care in administration and monitoring to maximize the benefits while minimizing adverse reactions.

How Long Do The Effects of Novocaine Last?

The effects of Novocaine typically do not last for a long time in the body. Novocaine is known for being the quickest-acting injectable anaesthetic. After it is injected, the numbing sensation usually begins within 5 to 10 minutes and lasts for about 30 to 60 minutes.

To extend the duration of Novocaine's effects, it is often combined with epinephrine also known as adrenaline, a vasoconstrictor that narrows blood vessels. When administered with epinephrine, the effects can last approximately 90 minutes.

Several key factors play a role in determining the duration of Novocaine:

  • Dosage: Variable doses are given based on the procedure type, size of numbed area, and number of nerves being blocked. Higher doses lead to more prolonged numbness.

  • Type of procedure: More complex procedures often require stronger, longer-lasting doses to achieve adequate numbness.

  • Numbed area size: Numbing larger areas necessitates larger novocaine doses, increasing duration.

  • Number of nerves blocked: Blocking more nerves requires higher doses, which lengthens numbness.

  • Desired numbing period: If an extended numbing time is needed to finish the procedure, providers may opt for a higher dose.

Novocaine Side Effects

It is essential to acknowledge that, like any medication, it comes with certain considerations, including potential side effects. According to Drugs.com, the most common side effects of local anaesthesia are numbness, tingling, and some minor pain around the injection site. These side effects are usually not severe and often subside within a few hours of the injection.  It is important to tell your dental professional right away if you experience any of them.

Novocaine Risks

Novocaine is typically quite safe when used properly under medical supervision. Dental professionals carefully calculate dosage to avoid potential overdoses. Combining it with epinephrine allows them to use less Novocaine while sustaining numbness, further reducing risks. The most common side effects involve minor injection discomfort - some burning as it goes in, followed by tingling and soreness at the site as it wears off.

However, in rare cases, severe reactions can occur, though major allergic reactions are very uncommon. Novocaine can provoke breathing and movement issues for hours in some due to genetic factors interfering with metabolization. If you feel numbness, it is good to take precautions like cautious eating and drinking, avoiding handling sharp or hot objects and protecting numb areas from trauma, until complete feeling comes back to protect numb regions from harm.

Your dental professional will decide the appropriate dosage of Novocaine for you. It is crucial to inform them about all the medications you are taking, whether over-the-counter or prescription and any existing health conditions to minimize the risk of experiencing any side effects from Novocaine.