What to Know About Skin-Numbing Creams

Skin-numbing creams are medications that function like a local anesthetic, reducing sensitivity to pain in the areas they are applied. These creams work by blocking nerve signals in the body.

The creams are used for a wide variety of purposes, such as before minor medical procedures or cosmetic procedures. They can also be used to treat pain from minor injuries.

Some skin-numbing creams are available over-the-counter (OTC), while others require a prescription. In either case, it's important to use the cream under the guidance of a healthcare provider.

This article explains the active ingredients in numbing creams, the differences between prescription and OTC numbing creams, and how to apply them. It also describes common side effects and when to call your healthcare provider.

Numbing Cream Uses

Numbing cream is often used to numb the skin before a medical procedure such as:

• Minor surgery
• Mammograms
• Childhood vaccinations or other injections

Increasingly, skin-numbing creams are also used before cosmetic procedures such as:

• Microdermabrasion
• Filler injection
• Waxing
• Body piercing
• Tattoo application

Skin numbing preparations are also available over-the-counter and by prescription to treat minor injuries and other causes of pain, such as:

• Sunburns
• Scrapes
• Cold sores
• Rashes
• Hemorrhoids
• Sore throat
• Insect bites

Active Ingredients

You may have heard of lidocaine, the active ingredient in most brands of skin-numbing creams. Lidocaine is very effective and has the benefit of providing quick results for pain relief.

Lidocaine can be found in skin-numbing creams like Dermoplast, LidoRx, and Lidoderm.

Other active ingredients in skin-numbing creams include:

• Benzocaine (found in Solarcaine, Dermoplast, and Lanacane)
• Pramoxine (found in Sarna Sensitive, Proctofoam, and Prax)
• Dibucaine (found in Nupercainal and Rectacaine)
• Tetracaine (found in Ametop gel, Pontocaine, and Viractin)

OTC vs. Prescription Numbing Creams

Over-the-counter skin-numbing creams may differ from prescription variations in strength and concentration. For example, a prescription-strength lidocaine patch (like Lidoderm) contains 5% of the active ingredient while a nonprescription variety (like Aspercreme) contains 4% of lidocaine.

Most OTC lidocaine medications are not approved by the Food and Drug Administration (FDA). However, some are marketed as "compliant" when the manufacturer follows the applicable FDA regulations.

Some topical numbing creams are mixed with hydrocortisone cream (for redness, itching, and swelling). One such brand is Peranex, which is available by prescription only. 

How to Use Skin-Numbing Cream

Follow the advice of your healthcare provider and/or the prescription label or product insert when using numbing cream. Check with your pediatrician before using a numbing cream on a child.

When you're ready to apply the cream:

• Wash the affected area with mild soap and warm water.
• Blot the area with a soft cloth.
• Apply a thin layer, as directed.

Be sure that you know:

• How much you should apply: In general, you will be advised to use the smallest amount possible to avoid the potential of a life-threatening overdose.
• Where you shouldn't apply it: Do not put numbing cream on skin that is red, swollen, sore, cracked, or scraped. Also, avoid the skin around your eyes. (Rinse your eyes thoroughly with water if you touch your eyes after applying the cream.)
• How long you should keep it on: If you leave large amounts of numbing cream on your skin for extended periods of time, the active ingredient may be absorbed into your bloodstream. This can cause life-threatening side effects, such as irregular heartbeat, seizures, difficulty breathing, and coma or death.
• When to apply it if used before surgery: For example, your provider may ask that you apply a numbing cream several hours before a surgical procedure. Starting the cream before this time is not helpful and can have negative effects.
  

Storage

Store numbing cream at room temperature, away from heat and moisture. Always keep the tube tightly closed.

Keep numbing creams out of the reach of children and pets.

Common Side Effects

Side effects should be minimal to non-existent if you follow your healthcare provider's advice on how to use a numbing cream. This said, it's possible that you could experience:

• Changes in skin color where the numbing cream was applied
• Itching or a rash
• Mild burning
  

To ease this, run the area under cool water (don't apply ice), then gently dry the skin.

When to Seek Medical Attention

Call your healthcare provider immediately if you (or your child) experience:

• Bruising or a purple-blackish haze appearing on the skin
• Confusion, blurred vision, or ringing in the ears
  
• Severe burning, stinging, or irritation where the numbing cream was applied
• Sudden dizziness or drowsiness
• Swelling or redness

Allergic reactions to numbing creams are similar to other allergic reactions. Call 911 if you (or your child) experience:

• Difficulty breathing
• Hives
• Swelling of the face, lips, tongue, or throat

If too much absorbs through your skin, you can experience an overdose, the signs of which include:

• Convulsions
• Rapid heartbeat
• Respiratory failure
• Coma

Call 911 immediately if you experience any of these symptoms,

This is not a complete list of possible side effects. Pay close attention and report any unusual physical events or changes to your healthcare provider.

Summary

Lidocaine is the active ingredient in many skin-numbing creams, though there are others. Prescription preparations of lidocaine are available in a 5% concentration of the active ingredient, while over-the-counter products contain a lower concentration.

It's fair to expect some minor side effects, such as changes in skin color, itching or a rash, or mild burning. Severe burning, irritation, or signs of an allergic reaction warrant medical attention.

Use the smallest amount of cream possible to numb your skin to avoid serious reactions.