Topical anaesthetics

What are topical anaesthetics?

Topical anaesthetics are used to temporarily numb your skin. They’re usually applied before a minor procedure, like a blood test or an injection. If you’re nervous about needles or sensitive to pain, they can make the experience much easier.

You can also use topical anaesthetics ‘off-label’ before a tattoo, cosmetic procedure or piercing.  Off-label means they’re not licensed to be used like this, but we know it works. You just have to chat to a clinician first.

Topical anaesthetics usually come as a gel or a cream, so you just spread it straight onto the area before you have the procedure. Then it desensitises the area and you’re ready to go.

How do topical anaesthetics work?

Topical anaesthetics are absorbed through the outer layer of skin and into the dermis, which contains the nerve endings. Topical anaesthetics focus on the nerve endings to block the pain sensation temporarily. It does this by inhibiting ion channels in the nerve cells, making it harder to pass the electrical impulses along the nerves, therefore effectively blocking the sensation of pain.^[1]

When should I use topical anaesthetics?

Topical anaesthetics are licensed to numb the skin before minor medical procedures like blood tests, injections and removing warts or bumps. It’s also used for more involved treatments, like removing the skin on a leg ulcer or having a cervical biopsy. In these cases, you should ask the practitioner performing the procedure if they can give you a topical anaesthetic.

They’re also used for cosmetic procedures. Some of these include dermal fillers, botox injections, laser hair removal, waxing, piercings and tattoos. This isn’t a licensed use, so you’ll need to tell your clinician so they can advise you. You should also tell whoever is performing the procedure that you’re using a topical anaesthetic.

What types of topical anaesthetics are there?

Most topical anaesthetics have active ingredients from one of two types of chemical compounds, esters and amides. Some examples of esters include procaine and tetracaine, and some amides include lidocaine and prilocaine. All of these have local anaesthetic effects.

Topical anaesthetics usually come as creams or gels, like EMLA Cream and Ametop gel. There are also topical anaesthetic sprays, often containing lidocaine. This is usually sprayed straight onto the throat before a dental procedure. It’s not usually used on the skin, because it isn’t absorbed as well as creams and gels.

Which topical anaesthetic should I use?

The type of topical anaesthetic you use will depend on what you’re using it for. That’s why it’s good to chat to a clinician first before you use them. There’s some evidence to suggest Ametop gel works better than EMLA cream for procedures that pierce the skin using needles, like blood tests. ^[1]

For laser and microneedling, LMX4 has been shown to outperform both Ametop gel and EMLA cream. ^[2] So it can really vary. Creams like EMLA and LMX4 are most commonly used for tattoos. It’s often easier to apply a cream than a gel over wider areas.

Remember that lots of topical anaesthetics have different active ingredients, so one might suit you better than another. For example, EMLA cream has lidocaine and prilocaine in it, while LMX4 Cream only contains lidocaine at a higher concentration. So if you’re sensitive to prilocaine, you might want to use LMX4 Cream instead.

How is topical anaesthesia different from other types of anaesthesia?

Topical anaesthetics are a type of local anaesthetic. Local anaesthesia means it affects only a specific area of the body and doesn’t lead to loss of consciousness. Topical anaesthesia is unique because it has the same properties as local anaesthesia, but it’s absorbed through the surface of the skin.

There are a few other types of local anaesthetic, like epidurals, where the anaesthesia is injected into your spinal cord to numb specific nerves. There’s also general anaesthesia, which causes unconsciousness, pain relief and memory loss and stops you from moving. This is usually used for more serious surgeries, because it comes with risks.