What is lidocaine used for?

What is lidocaine used for?

If you check some of the pain relief products in your bathroom or medicine cabinet, such as throat lozenges or sprays, you may find that they contain the ingredient lidocaine. But what exactly does lidocaine do and why is it included as an ingredient? Read on to find out.

What is lidocaine?

Lidocaine is a local anaesthetic that is used to numb a particular area. It does this by preventing specific areas of the body from sending pain signals to the brain via receptors. When these signals are blocked, the brain cannot sense the pain in the area, and so the sensation goes away temporarily. Cream that contains lidocaine is available on prescription and is sometimes used before having a drip put in or a blood test, particularly if you’re of a nervous disposition around needles.

According to the NHS, lidocaine gets to work quickly and is very safe for use in products like throat lozenges with minimal side effects. It can be used by most adults, as well as young adults over the age of 16. Some lidocaine products are suitable for young children and babies too[1].

What are the side effects of lidocaine?

Lidocaine can have a range of side effects with varying degrees of severity – some requiring medical attention and some not. If you experience any of the following side effects, you should speak to a doctor or nurse immediately:

  • Flushed or unusually warm skin
  • Bruising, swelling, bleeding or pain at the site of application
  • Cold, clammy skin or a bluish tinge to the lips or fingers
  • Chest pain, shortness of breath or difficulty breathing
  • Confusion, dizziness or loss of consciousness
  • A buzzing or ringing in the ears or hearing loss
  • A cough, sore throat, fever or headache
  • Fast, unusually slow or irregular heartbeat
  • Puffiness or swelling in the facial area
  • Fatigue, tremors or twitching

You may also experience other side effects, such as nervousness, nausea or vomiting, but these should ease as your body gets used to the lidocaine. However, if you are at all concerned about your symptoms or they are lasting longer than you expect, it’s always best to get the opinion of a medical professional[2].

How long does lidocaine last?

The numbing effect that lidocaine provides will last for anywhere from half an hour to three hours depending on the amount that’s applied. When taking throat lozenges that contain lidocaine, it’s recommended that you take one every two to three hours to numb the pain caused by a sore throat. You shouldn’t take more than eight within one 24-hour period[3].

What is lidocaine found in?

Lidocaine can be found in all sorts of products, from gels and creams to eye drops and sprays. This means that it can be used for pain relief in lots of ways and for different areas of the body[4].

  • Creams for general injuries

When an injury occurs, such as an insect bite or a scraped knee, it’s likely that you’ll want to get rid of the pain. Many antiseptic creams not only disinfect the wound but also help to numb the area too and may contain lidocaine or another similar ingredient, such as mepivacaine or prilocaine. These creams can also be used on sunburn, rashes and cold sores and are commonly used where needles are involved, such as before getting a tattoo or having blood taken.

  • Throat lozenges and sprays

Lidocaine is often found in products that help to numb the pain of a sore throat. Whether you have a cold or another type of infection, such as strep throat or tonsillitis, a sore throat can be painful and may prevent you from eating or swallowing easily. A throat lozenge can be sucked on to numb the area and make you more comfortable.

  • Injections at the dentist

When a dentist is required to perform work on your teeth, such as fitting a filling, they will use a local anaesthetic to numb the area and reduce how uncomfortable the experience is for you. Lidocaine is commonly used for this task and is injected into the gum to numb the mouth. The effects usually wear off after a couple of hours, but while the area is numb, you should avoid eating food, particularly hot food. This is to stop you from burning or biting yourself when you can’t feel anything.

  • Eye drops at the ophthalmologist

Eye drops that contain lidocaine are used by ophthalmologists before surgery on the eyes or if you’re experiencing pain in the area due to a scratch or abrasion. They are commonly used before laser eye surgery or cataract removal.

Can you buy lidocaine over the counter?

Lidocaine is available to buy over the counter as a cream and in throat sprays and lozenges. Always read the label carefully before you use any of these remedies, as lidocaine treatments often contain other substances which may not be appropriate for everyone to take. If you’re unsure about which treatment is the right one for you or your child, ask a pharmacist for advice[4].


[1] https://www.nhs.uk/medicines/lidocaine-for-mouth-and-throat/

[2] https://www.nhs.uk/medicines/lidocaine-for-mouth-and-throat/side-effects-of-lidocaine-for-mouth-and-throat/

[3] https://www.nhs.uk/medicines/lidocaine-for-mouth-and-throat/how-and-when-to-use-lidocaine-for-mouth-and-throat/

[4] https://www.nhs.uk/medicines/lidocaine-for-mouth-and-throat/about-lidocaine-for-mouth-and-throat/