Low prices. Quality service. Every day since 1945.

My Account
shopping cart0
Safco Logo
Free shipping on orders over $250

Signs a Patient is Having an Allergic Reaction to Dental Anesthetics

Signs a Patient is Having an Allergic Reaction to Dental Anesthetics


While there may be many factors pertaining to a dental visit that may pose a concern for your patients, a possible allergic reaction to local anesthetic may not initially be a factor that is considered. 


The possibility of a local anesthetic allergy may be understandably harrowing for your patients, but you can put them at ease by helping them understand that adverse reactions to lidocaine or novocaine are quite rare.


Knowing how to identify the signs of a dental anesthesia allergy and react to the issue at hand is absolutely crucial. In this article, we will discuss the signs of an allergic reaction to dental anesthesia, as well as the responsive steps that should be taken. It is important to note that this is for informational purposes. If you or someone you know is experiencing symptoms of an allergic reaction, we recommend consulting a health practitioner.


Safco Dental Supply is proud to be your trusted source for quality dental supplies; we provide a wide range of both injectable anesthetics and topical anesthetics


What is an Anesthesia Allergy?

To better understand anesthetic allergies, it is important to first understand what an allergy actually is.


Allergies occur when the immune system fails to recognize a certain substance and creates an overreaction to it in order to “protect” the body. These substances, known as allergens, may range anywhere in nature from pet dander to anesthetic substances. An allergic reaction can range in severity from slight discomfort to life-threatening.


So, can you be allergic to anesthesia? In most cases, a true allergic reaction is extremely rare. In fact, it is currently estimated that just 1% of all reactions that occur during local anesthesia are due to “true” anesthesia allergies.


In most cases, adverse symptoms that are experienced after the use of local anesthesia are typically attributed to an adverse reaction to epinephrine. 


Epinephrine is used in local injections to ensure that the blood vessels constrict, decreasing blood flow to the area and ensuring that the anesthesia is as effective and long-lasting as possible.


Adverse effects or allergic reactions may also occur due to an allergy or sensitivity to:

  • Latex
  • Sulfites
  • Preservatives (such as methylparaben or propylparaben)
  • Antioxidants


What are the Symptoms of Having an Allergic Reaction to Dental Anesthesia?

To understand the symptoms of an allergic reaction to anesthesia, you have to know what kind of anesthesia you may have been administered. In most cases, there are two types of anesthetics that may be used for local injections: lidocaine and novocaine. 


Novocaine has been used in dentistry since the early 1900s. For decades, it was the dental industry’s standard numbing agent. While it has proven to be safe and effective in most cases since its introduction, it may sometimes produce side effects such as anxiety, dizziness, allergic reactions (swelling/redness) at the injection site, or restlessness. 


Lidocaine was developed as a successor to novocaine in the late 1940s and is now the most commonly-used dental anesthetic. Lidocaine does not take as long as novocaine to take effect, lasts longer, and produces less risk of side effects. 


While a true allergic reaction to dental anesthetics is rare, they do occur. Below, we will break down the common symptoms of lidocaine and novocaine allergies.


Lidocaine Allergy Symptoms

In the case of an allergic reaction, knowing which symptoms to watch for can help you identify and treat the issue as fast as possible.


Some common allergy to lidocaine symptoms include:

  • Anxiety
  • Anaphylaxis
  • Edema
  • Nausea
  • Vomiting
  • Hyperventilation
  • Changes in blood pressure or heart rate
  • Unconsciousness
  • Sweating
  • Urticaria
  • Swelling of the tongue, face, and/or lips


Novocaine Allergy Symptoms

In most cases, the local anesthetic reactions that are associated with novocaine are similar to the reactions that are associated with lidocaine. 


Common novocaine anesthesia reactions symptoms include: 

  • Anxiety 
  • Anaphylaxis
  • Nausea
  • Vomiting
  • Hyperventilation
  • Changes in blood pressure or heart rate
  • Unconsciousness
  • Sweating
  • Urticaria
  • Swelling of the tongue, face, and/or lips
  • Dizziness
  • Swelling/redness at the injection site
  • Restlessness


It is important to remain diligent and watch for signs of these symptoms throughout your patient’s visit. Even if symptoms do not appear immediately after injection, some patients may experience a delayed allergic reaction to novocaine or lidocaine.


What Should You Do if You Suspect a Patient Has an Anesthesia Allergy?

If you notice any of the above symptoms after you have administered anesthesia, you may begin to suspect that your patient has a dental anesthesia allergy. In this case, it is best to have a plan in place to manage your patient’s health. 


Below are some actions that may be taken to minimize adverse local anesthetic reactions:

  • Encourage the patient to stay as relaxed as possible
  • Lower the patient to a supine position with legs elevated to prevent fainting and regulate blood pressure
  • Loosen any tight clothing and/or remove tight jewelry around the patient’s neck
  • Provide the patient with a glucose drink
  • Refer the patient for thorough allergy testing


If a true allergic reaction has been identified, the patient should be referred directly to the allergy clinic inside the hospital. If the patient appears to be exceptionally distressed or is presenting life-threatening symptoms (such as anaphylaxis), they should immediately be transferred to the hospital for emergency treatment. 


Anaphylaxis is typically treated with an injection of epinephrine or antihistamines. Intravenous fluids may be used, as well.


If the direct cause of the symptoms can not be identified with certainty, contact should be made with the hospital to refer the patient and discuss the findings of further investigations.


Ensure that your patient understands the importance of requesting local anesthetic allergy alternatives – such as septocaine or mepivacaine – during any dental work that they receive in the future. An annotation should be made in their chart, as well.


How Safco Keeps Patients a Priority

We know that as a dental professional, the health and safety of your patients is priority number one. Here at Safco Dental Supply, we share your passion and dedication for your patients, as well.


With the information you have learned here, you are now equipped with a solid understanding of how to treat an allergic reaction to lidocaine or novocaine. While allergic reactions to local anesthetics are rare, it is important to have a responsive plan in place.


For high-quality dental products, place your trust in Safco Dental Supply. We provide a wide range of products to fit every need, with free shipping on orders over $250.


We strive to get you your products as fast as possible. All orders placed before 4:30 pm CST (3:30 pm on Friday) are shipped out same-day.


Give us a call at 800.621.2178 to speak with one of our experts.

Leave a Reply