Can You Be Allergic to Novocaine?

You may have an upcoming appointment for a dental procedure that requires a local anesthetic, but are wondering if a person can be allergic to Novocaine.

You might be glad to find out that, while it is possible to have an allergic reaction to Novocaine, true allergies to general or local anesthetics is exceeding rare. In fact, the incidence ranges from 1 in 5,000 to 25,000 cases.

Some people are sensitive to anesthetics and other medications, but not allergic to them. Symptoms of drug sensitivities include shaking, sweating, feeling faint, and experiencing heart palpitations.

If you have used Novocaine successfully in the past, it is less likely that you will suffer an allergic reaction to Novocaine than would someone who has never been exposed to the local anesthetic.

What is an Allergy?

An allergy is a state in which your body’s immune system detects an otherwise harmless substance, known as an allergen, and overreacts to it.

People can be allergic to a number of things, including pollen and certain types of food or drugs. Individuals can also have allergies to latex, a common ingredient of the gloves worn by dental and medical professionals.

Allergic reactions can range in severity from mild skin rashes to anaphylaxis, which is a severe form of allergic reaction. Anaphylaxis can cause swelling of the airway that can cause difficulty breathing.

Symptoms of an allergic reaction to local anesthetics, such as Novocaine, include:

  • Skin reactions, such as rash, hives, itching, or swelling
  • Asthma-like symptoms
  • Anaphylactic shock in extreme cases

While some allergic reactions can be dangerous, most are not. In fact, most people who suffer an allergic reaction to local anesthetics experience only temporary itching and skin rash at the site of the injection. While it can happen, anaphylactic shock resulting from Novocaine and other local anesthetics is extremely rare.

Allergic Reactions to Other Chemicals in Local Anesthetics

People can experience an allergic reaction to other chemicals in local anesthetics, such as epinephrine and preservatives.

Most formulations of local anesthetics also contain epinephrine, for example, which constricts the blood vessels at the injection site. Making these blood vessels smaller helps the Novocaine work in several ways. First, constricting the blood vessels decreases blood flow to the area, so that the Novocaine stays near the injection site longer. This means epinephrine helps the numbing power of Novocaine last longer.

Local anesthetics may also contain preservatives to keep the epinephrine fresh. Allergies to these preservatives or to epinephrine are also rare, and reactions are often the result of sensitivities rather than true allergies. Many patients who experience sensitivities to epinephrine or preservatives, however, may worry that they are allergic to Novocaine.

Central Nervous System Reaction

Sometimes local anesthetics can cause a reaction in the nervous system rather than in the immune system. Novocaine can sometime interfere with the way the central nervous system functions. Your dentist should thoroughly review your medical history before administering Novocaine to determine the proper dose and to make sure you do not have any pre-existing medical conditions that would increase your risk for a central nervous system reaction.

An excessively high dose of Novocain may cause central nervous system symptoms, such as nervousness and dizziness. In rare cases, high doses of Novocaine may cause respiratory failure. A careful review of your medical history and assessment of your health can reduce your risk for central nervous system reactions.

What Your Dentist Can Do

If you are concerned that you might be allergic to Novocaine, speak with your dentist. Your dental health professional can review your signs and symptoms to help you determine whether you can use Novocaine safely for dental procedures.

Ask your dentist if he or she will be using Novocaine. People in the United States often use the word Novocaine when they talk about local anesthetics, even though most dentists have used lidocaine for local anesthesia since the 1980s.

Notify your dentist of any side effects you may have experienced after the use of Novocaine before undergoing any treatment that requires local anesthesia. Informing your dentist of your history of an allergic reaction, sensitivity, or central nervous system reaction can help your dentist take proper measures to respond to any signs of a recurrence during procedures requiring Novocaine.