Medical expert of the article
New publications
Lidocaine allergy
Last reviewed: 05.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Lidocaine is a well-known drug used by doctors as a local anesthetic. However, in some individual situations, lidocaine can cause an allergic reaction. An allergy to lidocaine can manifest itself almost harmlessly in the form of common urticaria or dermatitis. But in a severe form, the situation becomes much more complicated, because a number of complex allergic reactions can occur, such as edema, bronchial asthma and rhinitis, anaphylactic shock, allergic vasculitis, Quincke's edema.
Very often this drug is used in dentistry. And sometimes lidocaine can cause intolerance in some patients. This situation becomes big news for people who have not previously had any signs of allergies. And for people prone to allergic reactions, immunologists and allergists advise to first do a test and conduct a number of specific tests, and only after that is the use of lidocaine allowed. Otherwise, the treatment can lead to very serious consequences and even death. Therefore, if you are facing treatment using local anesthesia, it is very important to know how your body will react to this local anesthetic.
Causes of Lidocaine Allergy
The reasons for allergy to lidocaine are its wide range of side effects and its complex chemical composition, which can make even a healthy person feel unwell, and a typical allergy sufferer will suffer for a long time.
Genetic predisposition may also be the cause of an allergy to lidocaine. However, doctors claim that lidocaine itself is extremely rarely the true cause of an allergy. Since in fact, most of the side and negative reactions to lidocaine are associated with vegetative-vascular disorders of the nervous system, mental dysfunctions, and a reaction to the toxins contained in the drug. True allergic symptoms may be caused not so much by the drug itself as by its additives. For example, methylparaben, which is part of the paraben group, is very often used as a preservative, has a powerful antiseptic effect. Substances of the paraben group can cause increased sensitivity of the body and anaphylactic shock. Therefore, if a patient suffers from an allergy to this additive, then the use of lidocaine becomes inappropriate, since methylparaben is part of it.
It is worth remembering that drug intolerance and allergy are similar but completely different phenomena. Therefore, an allergy test is necessary in any case.
The thing is that with any impact on the human body, lidocaine begins to react very quickly, stabilizing neuronal membranes and reducing permeability for sodium ions, and this prevents the appearance of action potential and impulse conduction. That is, your brain does not receive a signal about pain from the place of application or injection of lidocaine. And as a result of such complex chemical processes, the body may not cope and not accept the medicine.
How does an allergy to lidocaine manifest itself?
Symptoms of an allergy to lidocaine also need to be distinguished from the symptoms of a side effect. Therefore, carefully study the symptoms of each of the phenomena in order to understand what is happening to your body if your reaction to lidocaine is not normal.
- An allergic reaction causes urticaria or dermatitis, which are accompanied by severe itching of the skin, conjunctivitis and a runny nose, swelling of the upper and lower lips, cheeks and larynx, which usually leads to difficulty swallowing and breathing, and in extremely severe cases, anaphylactic shock occurs.
- In case of intolerance to the drug, the patient's symptoms may vary. At first, poor health may manifest itself in the form of dizziness, nausea and vomiting, then drowsiness and apathy appear, and visual impairment is also possible. Due to dizziness, consciousness becomes unclear, and breathing is weakened. In more complex cases, arrhythmia and low blood pressure are very likely. Anaphylactic shock and cardiac arrest are the most terrible consequences of an allergic reaction to lidocaine. However, experts most often testify that reactions of this kind are possible only with an overdose of lidocaine.
Allergy to lidocaine in a child
The child's body, due to its development and changes in the immune system, can react to lidocaine in completely different ways. Thus, during the first interaction with the anesthetic, everything may be fine and without deviations, and the next time the child may have an allergic reaction to lidocaine or similar drugs. Therefore, it is very important to do an allergy test right before the treatment procedure.
If the allergy test is positive or there is a general intolerance to lidocaine, then sevoflurane - introductory and maintenance general anesthesia - can be an alternative. Its inhalation administration helps the patient quickly lose consciousness and quickly recover after the anesthesia is over. This form of anesthesia is an order of magnitude more expensive than local anesthetics, but it is very effective, and the treatment procedure with its help for the child is painless.
Diagnosis of allergy to lidocaine
Diagnosis of lidocaine allergy is as follows:
- If there is a sudden suspicion of an allergic reaction to any anesthetic, then its use is immediately reduced. But it is often almost impossible to categorically exclude pain relief with these drugs, since their alternative solution is general anesthetics, and this is a fairly serious replacement that increases the likelihood of complications. Moreover, such local anesthetics as lidocaine and procainamide are most often prescribed for arrhythmias, and they are almost irreplaceable by others. In any case, it is always necessary to assess the risk that the anesthetic can cause to the patient, and to measure this risk against possible complications after refusing lidocaine.
- If previous reactions, regardless of whether allergic or non-allergic, have resulted in a number of unfavorable consequences, then it becomes necessary to completely abandon the use of lidocaine in any form.
- Before conducting a skin provocation test, the patient is informed about the purpose of the test for the body's reaction, and warned that there is a possibility of non-standard reactions and complications. Often, written consent is taken for the examination, and if the test is performed on a child, then written consent from his parents is required.
- The ideal accuracy of skin tests with lidocaine has not been established, but doctors recommend starting with it when choosing a safe pain reliever.
- If the lidocaine provocation test is negative, the risk of side effects when using the drug is minimal.
If you do not want to take risks or already know how your body may react to the drug, then you need to do an intradermal test. It is done by a nurse using a thin insulin needle, and after fifteen minutes, the doctor evaluates the patient's condition before the planned operation.
Allergy to lidocaine: what to replace the anesthetic with?
It is very easy to replace lidocaine with another local anesthetic drug these days due to the rapid development of medicine. There are many drugs that are similar in action to lidocaine, but do not cause strong side effects. For example, BlokkoS, it is four times stronger than lidocaine. It is also used for injuries and the need for surgical intervention, with its help, pain relief during childbirth is carried out, and is also widely used in dentistry.
There is another proven method of combining local anesthetics and epinephrine. It is used for immediate allergic reactions that develop when using medications or when reactions such as urticaria, anaphylactic and angioedema shock, eating food, insect bites or the introduction of other allergens.
Very often, patients who have any allergic or side effects to local anesthetics, almost every doctor will recommend excluding the use of all drugs ending in "-caine", since their principle of action is almost the same. But it is worth remembering that if you have at least once had an unusual reaction to a painkiller, then you need to do a special test before each procedure.
Treatment of lidocaine allergy
At home, you can get rid of an allergic reaction to lidocaine in the following ways:
- If dermatitis or hives appear, you need to take a cool shower, a cold compress on the rash will also help. Such measures will help get rid of redness and severe itching caused by allergies. An ointment for sunburn will also help reduce itching. The fabric of clothing should not provoke itching and irritate the skin.
- Even if a person cannot call himself an allergy sufferer, he should have an antihistamine in his medicine cabinet, because in case of an unexpected allergic reaction, its use is necessary.
- If you experience difficulty breathing, you should definitely take a bronchodilator.
- If you feel dizzy, you need to immediately give your body a rest. Lie down on the bed so that your legs are higher than your head. Resting in this position will help normalize your blood circulation.
- If vomiting begins, this is a clear sign that the body needs to be cleansed. It is necessary to wash the stomach with sorbents. The simplest of them, for example, is activated carbon.
- You need to drink more water to quickly remove from the body all the harmful substances that are used as additives and stabilizers in lidocaine.
And, of course, you should limit the use of this anesthetic and, if possible, replace it with another one that is less harmful to your body. In the future, be sure to consult a doctor, take tests, and never forget to warn the medical staff that you are allergic, since most serious medical procedures are carried out by anesthetizing the patient with lidocaine beforehand.
Medical care for an allergic reaction to lidocaine:
- At the hospital, medical workers will quickly block the further spread of the allergen throughout the body with special drugs.
- In case of anaphylactic shock, 0.1 to 0.5 ml of adrenaline is administered.
- First aid for an allergy sufferer, further treatment and recovery after contact with an allergen is treated by administering glucocorticosteroids and antihistamines.
- The patient then undergoes symptomatic therapy.
Prevention of allergy to lidocaine
The best way to prevent or minimize an allergic reaction to lidocaine is to try to avoid contact with it and find an alternative. In this case, it is very difficult and burdensome, since it can cost a lot of money, because of this, the symptoms of an allergy to lidocaine are very difficult to control. But it is best to inform your doctor as a preventive measure before medical procedures that you are worried about your reaction to lidocaine and want to do a skin test. After this procedure, the doctor will be able to determine whether there is a positive or negative reaction to the drug. And if the test reveals problems, the doctor will find an alternative method of local anesthesia, or use general anesthesia with sevoflurane. Before prescribing lidocaine as an anesthetic, it is necessary to carefully study its properties and the presence of cross-reactions with other drugs and foods.
It is highly recommended not to attempt to eliminate an allergic reaction to lidocaine on your own, as there is a very high probability of worsening the patient's condition. When the first worrying symptoms appear, you should consult a doctor and follow his strict recommendations.