Lidocaine Uses & Side Effects

Lidocaine hydrochloride is a local anesthetic agent that causes numbness to provide temporary relief from pain. It has been used for local anaesthesia since the 1940s. Lidocaine has a rapid onset of action and a good safety profile. Please continue reading to learn more about lidocaine pharmacokinetics, uses, and side effects.

Is lidocaine a narcotic?

No, lidocaine is not a narcotic. It is a local anesthetic agent that blocks pain signals in the nerve endings of the skin where it is applied. The use of lidocaine only provides local anesthesia in the affected area. It is not a general anesthetic, which induces a sleep-like state used in combination with other medicines. Lidocaine and other local anesthetics are not addictive. They do not fall under controlled classes of drugs such as opioids, stimulants, or hallucinogens.

How do local anesthetics work?

Local anesthetics such as lidocaine work by blocking sodium channels on the internal surface of nerve cell membranes. They lock the sodium ion channels in nerve cells in a permanently open state, thus preventing nerve depolarization. This prevents peripheral nerves from sending pain signals to the central nervous system. Interestingly, lidocaine doesn’t work as well in the presence of inflammation. Many factors contribute to this, though. It is believed that increased blood flow can reduce the efficacy of lidocaine, in addition to the production of inflammatory mediators such as peroxynitrite, which interact with lidocaine and affect how it works.

What kind of pain is lidocaine good for?

Topical lidocaine can provide temporary relief from pain and discomfort caused by minor burns, cuts, sunburns, and other skin irritations. A lidocaine patch is good for nerve pain in a small localized area. Viscous lidocaine is used to numb teething pain and painful sores in the mucous membranes of the mouth. Topical lidocaine is available in various forms, such as ointments, gels, creams, foams, and patches. Many of these products are available over the counter. They are applied directly to the surface of the skin in the affected area.

Lidocaine is also used to treat pain during medical procedures. For example, intravenous lidocaine is used to provide intravenous regional anesthesia for surgical procedures such as carpal tunnel surgery and fracture reduction. It is also used in epidural anesthesia (for treating pain during labor and delivery). Lidocaine is also used in spinal anesthesia, such as for hip and knee joint arthroplasties.

Additionally, injectable lidocaine is an antiarrhythmic agent used to manage cardiac arrhythmias and cardiac arrest.

What is the major side effect of lidocaine?

A major side effect of lidocaine can be burning, redness, swelling, and discomfort in the skin where it is applied.

Rarely, more serious adverse effects can occur after using local anaesthetics. Call your doctor without delay or get immediate medical care if you develop adverse reactions such as:

Skin rash, hives, itching, blisters, or bruising in the subcutaneous tissue
Swelling of the face, eyes, lips, tongue, mouth, or throat
Respiratory depression or respiratory arrest (slowed or stopped breathing)
Difficulty breathing or swallowing
Hoarseness
Fast breathing
Fast pulse
Nausea and vomiting
Unusual thirst
Confusion
Weakness
Dizziness
Fainting
Skin color changes (pale blue or gray skin)

Who should not use lidocaine and other local anesthetic agents?

People who have an allergy to lidocaine should not use this drug. Tell your doctor if you have ever had an allergic reaction to lidocaine, other local anesthetics, or any other drugs. Your doctor may advise you not to use lidocaine.

Interactions between lidocaine and other medications can lead to serious adverse reactions. Give your doctor a complete list of your medications, including prescription drugs, over-the-counter medications, dietary supplements, and herbal products. This will help avoid potentially dangerous drug interactions.

Lidocaine may not be right for everyone. Give your healthcare provider a complete medical history. Specifically, tell your doctor if you have a condition called G6PD deficiency or methemoglobinemia. Also, tell your doctor if you have heart, lung, or liver disease.

How to use lidocaine safely?

Apply lidocaine on intact skin as directed. Check with your healthcare provider whether to use an occlusive dressing. For example, EMLA (eutectic mixture of local anesthetics) contains two local anesthetics, lidocaine and prilocaine, and is applied under an occlusive dressing such as a Band-Aid, Saran wrap, or Tegaderm to aid absorption into the skin of the affected area and surrounding tissues.

An overdose of lidocaine is rare, but it is possible. Using lidocaine at high doses, applying lidocaine to large areas of the body, or injecting it into many areas of the body can lead to a high lidocaine concentration in blood and symptoms of an overdose. Read the prescription label or package label carefully and use lidocaine exactly as advised.

Call the National Poison Control Center at 1-800-222-1222 and seek emergency medical attention if you develop symptoms of an overdose such as dizziness, lightheadedness, confusion, nervousness, vision changes, ringing in the ears, vomiting, feelings of numbness, hot or cold, uncontrolled shaking or twitching, seizures, or slow heartbeat.

Note: The above lidocaine information is for educational purposes only. It should not be used as a substitute for professional medical advice. Talk to your healthcare providers or health system pharmacists for further information about lidocaine uses and side effects.

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