Why does Lidocaine reduce pain?

Lidocaine, a well-liked local anesthetic, has become a standard choice for pain control during surgical and dental operations. Due to its ability to lessen discomfort and dull feelings, it has evolved into a crucial tool in healthcare settings. But why does lidocaine work so well to relieve pain? Here is an ultimate guide to strong lidocaine creams. The rich and powerful analgesic effects of lidocaine are underpinned by a variety of intricate biological mechanisms, which we describe in this article.

Lidocaine works to relieve pain by specifically interacting with and targeting nerve cells. Binding to the voltage-gated sodium channels found in these cells is one of its main functions. Lidocaine prevents the entry of sodium ions through these channels, interfering with the generation and transmission of pain signals. This interference with the dehydration process reduces pain perception significantly because it prevents nerve cells from effectively delivering pain signals to the brain.


The local anesthetic and antiarrhythmic drug lidocaine has a long, illustrious history. The creation and use of lidocaine have revolutionized medical operations and pain management, making it a crucial part of contemporary healthcare. Here is a synopsis of the development of lidocaine:

When scientists began investigating the possible uses of local anesthetics in the early 20th century, lidocaine first appeared. The drug lidocaine, formerly known as xylocaine, was created in Sweden in the 1940s by a group of scientists under the direction of Nils Löfgren. It was one of the first synthetic local anesthetics to be created, and because of its strong analgesic effects, it soon attracted attention.

Early uses of lidocaine focused mostly on dental operations because of how well it worked to numb the mouth. Its success in dentistry cleared the path for its extension into other specialties of medicine, such as obstetrics, surgery, and dermatology. Due to its quick onset of action, lengthy duration of effect, and general safety profile, lidocaine was frequently used.

Lidocaine continued to develop throughout the ensuing decades, with improvements in both its formulations and administration strategies. Topical creams, gels, ointments, and sprays were created to treat skin-related disorders and offer localized anaesthetic for quick treatments. Lidocaine injections have grown in popularity for use as nerve blocks and regional anaesthetic during surgical procedures.

Lidocaine’s uses grew over time, becoming useful for pain control outside of urgent surgical circumstances. It became a well-respected choice for treating chronic pain problems such post-herpetic neuralgia and neuropathic pain. In order to provide convenient and non-invasive regional pain treatment, lidocaine patches were created.

Lidocaine HCI local anesthetic cartridge

What is this Medication?

Anesthetic LIDOCAINE (LYE doe kane). It results in numbness in the tissues around the skin. It helps both prevent and cure pain brought on by certain operations. Additionally, small burns, scratches, and insect bites are treated with this medication.

If you have any questions, speak with your doctor or pharmacist. This medication may also be used for other conditions.

Clinical Considerations

To reduce potential side effects, studied lidocaine doses of 1 to 1.5 mg/kg for acute pain can be gently given over 10 minutes or longer on a pump. Due of lidocaine’s brief 1.5–2 hour half-life, AEs are typically transitory and swiftly reversible. Dizziness, dysarthria, a metallic taste in the mouth, and numbness are typical adverse events (AEs), and they tend to accumulate after many doses. Since analgesic doses are less than half of the lethal doses of 4 mg/kg, monitoring of plasma levels is not advised. Even when plasma levels drop, lidocaine may still have analgesic effects. Clinicians should carefully examine use in patients who are elderly or have a bad cardiac history. Studies have inconsistently verified cardiac monitoring while receiving IV lidocaine. Excessive analgesic doses should only be used in critical care regions, according to practitioners.

The use of IV lidocaine as an additional nonopioid therapy option for acute pain is supported by preliminary research, particularly in the management of migraines, perioperative pain, and renal colic.


When deciding whether to utilize local, regional, or general anesthesia, healthcare providers will take into consideration a number of criteria. The following circumstances are often appropriate for local anesthesia:

  • Since the surgery is simple, no general anesthesia nor local anesthetic are needed.
  • The process takes only a short amount of time, and no overnight stay is required.
  • It is not necessary for the person to be unconscious or for the muscles to be relaxed.

The removal of a verruca, mole, or cataract is an example of a technique that uses a a local anesthesia, as are dental surgery, biopsies, and other medical operations.


The patient’s age, weight, allergies, and medical conditions, as well as the location and purpose of the surgery, will all have an impact on the type and dosage of anesthetic.

Medical experts can administer several medications as an injection, spray, or ointment to block pain.

The medicine prevents the nerves in the application region from delivering signals to the brain by acting on certain nerve pathways.

The medicine often takes effect within a few minutes and wears off within a few hours. A stronger dose will have a longer effect.

Although cocaine was the first anesthetic, it is now rarely used. The most popular local anesthetic is lidocaine, however doctors and anesthetists utilize various medications for various conditions.

Longer procedures are better suited for bupivacaine, but the drug’s administration can be more unpleasant than with other medications. If numbness is required for a longer duration, an anesthetist may use lidocaine first and then administer bupivacaine.

Despite having a structure that is similar to that of cocaine, synthetic anesthetics do not have the same potential for abuse.

Side Effects

An individual may experience some tingling, pain, and discomfort as the anesthesia is administered and is wearing off, as well as some bruising, but these side effects are often modest.

A person who has received a local anesthetic should take extra caution to avoid hurting themselves while they are numb to pain, such as by biting their cheek after receiving dental treatments.

Temporary negative impacts that some people experience include:

  • blurred vision, dizziness, and vomiting
  • headaches
  • muscle twitching
  • continuing numbness, weakness, or tingling

Additionally, some people are susceptible to allergic reactions that cause hives, itching, and breathing problems.

Additionally, issues with blood circulation or inadequate blood oxygenation can occasionally result in cyanosis, a condition where the skin appears blue or grey in persons with darker complexion.

Additionally, a local anesthetic overdose can cause life-threatening convulsions, according to Trusted Source.


  • Lidocaine is used as a local anesthetic to numb certain body parts prior to minor surgical, dental, or other operations because it blocks the transmission of pain impulses. Lidocaine has a very immediate effect.
  • Can be taken with epinephrine, which boosts the anesthetic effect’s intensity and duration and constricts blood vessels to lessen bleeding.
  • Lidocaine can also be used to create localized anesthesia, which is the loss of sensation in a particular body part, such as an arm, a leg, or the entire pelvic area.
  • The emergency treatment of cardiac arrest, ventricular arrhythmias, or other severe heart problems may involve the use of lidocaine antiarrhythmic.
  • An IV is used to give systemic lidocaine. In the US, the IM formulation is no longer offered commercially. For the initial management of ventricular arrhythmias, administer as an IV bolus.
  • In renal impairment, there is no need to change the dosage.
  • Is a last-resort option for treating status epilepticus (systemic lidocaine).


You are more likely to have the following side effects if you are between the ages of 18 and 60, do not take any other medications, or have any other medical conditions:

  • When lidocaine is used as a local anesthetic, skin redness, irritation, a rash, or a sensation of warmth may develop in the affected area. Less frequently experienced at the injection site include bruising, bleeding, edema, and pain.
  • When used to treat cardiac arrhythmias, stop the infusion the moment the heart’s fundamental rhythm seems stable or at the first indication of toxicity. If the PR interval is prolonged, the QRS complex appears, or arrhythmias worsen, stop the infusion.
  • With lidocaine antiarrhythmic, side effects such as dizziness, sleepiness, nausea, or vomiting, a sluggish heartbeat, and low blood pressure may be more severe. The common manifestation of high blood lidocaine levels is drowsiness.
  • Confusion, seizures, and respiratory depression are some of the negative effects that local anesthetics injected into the head or neck region might cause.
  • IM lidocaine may increase creatine phosphate levels after a heart attack, which may impact testing for this enzyme.
  • Some individuals, such as those with congestive heart failure, myasthenia gravis, low blood pressure, liver or kidney illness, or respiratory, cardiovascular, or cardiovascular diseases, may not be suited. Patients with liver illness must administer medications carefully.
  • Some drugs, such as beta-blockers, cimetidine, antiarrhythmics, and HIV agents, may interact with one another.
  • It is advised to continuously monitor your ECG.

Lidocaine ampoule

Is it Safe?

Local anesthetic is typically thought to be highly safe by medical practitioners. It is more secure than general anesthesia for small surgery.

In extreme circumstances, patients may suffer life-threatening consequences. One of these is central nervous system depression, when the neurological processes of the body slow down excessively and result in a slowed heartbeat and breathing rate. If the blood supply to the heart is cut off, this condition may result in cardiac arrest.

A reaction to an allergen may also occur in certain people, which may cause hives, swelling, and breathing problems. Anaphylaxis is a medical emergency characterized by a severe allergic reaction that necessitates immediate medical attention.

Seizures are yet another potential complication trusted source. Although uncommon, young children are more prone to experience them than adults.

Due to these factors, even though local anesthetic is typically safe, it should only be administered by qualified individuals.


The doctor should explain how to get ready if a patient is having surgery or another operation that requires a local anesthetic.

If a patient is taking any drugs, especially blood thinners like aspirin or warfarin, they should let their doctor know.

The patient could be told by the doctor to fast for a few hours before to the procedure. Additionally, it’s crucial to abstain from alcohol for 24 hours before to the anesthesia.

In the doctor’s office, local anesthetic is frequently administered to patients. The affected area of the body will start to feel numb shortly after the doctor injects it with a local anesthetic.

If the patient does not experience the numbing effect, the doctor will stop the treatment. They won’t feel any pain during the surgery due to the anesthesia, but they might still feel pressure.

The doctor might also administer a sedative, depending on the nature of the treatment and how anxious the patient is. The person will feel more at ease and less apprehensive because of this drug.

The patient’s finger will frequently receive a little device from the doctor so they can keep an eye on the blood’s oxygen level. Rarely, they could use a plastic nasal tube to deliver additional oxygen.

Other Applications

Additionally, local anesthetic can be used by medical experts to diagnose some chronic illnesses and lessen post-operative discomfort.

A local anesthetic may be more effective at treating pain after total knee replacement surgery than opiates like morphine.

Local anesthetics were reported to reduce some of the symptoms of inflammatory bowel disease in rats in an earlier study from 2010. To confirm whether the medications have this impact on humans, more research is required.


Lidocaine’s precise interactions with nerve cells are thought to be the cause of its pain-relieving effects. Lidocaine efficiently numbs the afflicted area by preventing the transmission of pain signals through sodium channels. By stabilizing nerve cell activity, its regulation of potassium channels makes a further contribution to pain relief. Additionally, the anti-inflammatory qualities of lidocaine aid in reducing inflammation-related pain. With a long history of usage and wide distribution, lidocaine still plays a crucial part in pain treatment, offering efficient pain relief and enhancing the quality of life for countless people.