A skin numbing cream can be an effective way to make both medical and cosmetic procedures easier. Dermatologists in particular find that a skin numbing cream is useful in a variety of situations they encounter on a daily basis. Aestheticians use numbing creams to make cosmetic treatments safer and less painful.
A skin numbing cream can be used before a variety of procedures including:
- Removal of skin lesions
- Laser resurfacing (ex. Fraxel, Pixel)
- Laser treatment of vascular and pigmented lesions
- Thermal and ultrasound treatments (ex. Ultherapy)
- Tattoo removal (ex. Q-switched laser tattoo removal)
- Waxing, laser hair removal (ex. YAG laser hair removal)
- Injections (ex. Botox, fillers)
- Chemical peels
Skin numbing cream ingredients
Lidocaine was first synthesized in 1943 and since then many other topical anesthetics have been made. The two main types of topical anesthetics are amide and ester anesthetics. Both are effective but differ in how they are metabolized. In general, amide-type anesthetics are less likely to cause an allergic reaction. Even in the case of amide-type anesthetics, however, allergic reactions to topical anesthetic are rare.
A topical numbing cream penetrates through the outer layer of skin to the nerve endings in the dermis. Topical application in a cream allows the anesthetics to penetrate the nerve membrane. Once they reach the dermis, amide-type and ester-type anesthetics both behave the same way by blocking sodium channels to prevent nerve cell impulses from being made.
EMLA numbing cream
One of the more well-known numbing creams available is called EMLA (eutectic mixture of local anesthetics). This is a combination of lidocaine 2.5% and prilocaine 2.5% (two amide-type anesthetics) in one cream. This cream is sometimes used as a topical pain reliever as opposed to a pre-procedure numbing agent. While EMLA cream may be effective for pain relief for minor injuries, it is not usually strong enough to numb the skin prior to a procedure like microneedling or laser resurfacing.
What is the strongest skin numbing cream?
The strongest numbing cream that is used by dermatologists is a triple anesthetic cream. The most common formulation is a combination of benzocaine 20%, lidocaine 6%, and tetracaine 4%, which is also called BLT cream. BLT cream is the most frequently requested skin numbing cream at our compounding pharmacy. This combination can effectively remove pain associated with minor surgery and cosmetic treatments. Benzocaine and tetracaine are ester-type anesthetics and lidocaine is an amide-type anesthetic. Combined together they produce more effective anesthesia than when each is used alone. Besides the strength of this combination, BLT cream also has a rapid onset and long duration.
The ingredients in BLT cream each have different durations of effectiveness and time to onset that contribute to the overall effectiveness of the combination. The longest lasting ingredient is tetracaine followed by lidocaine and benzocaine. Benzocaine, however, has a faster onset than tetracaine. Other strengths are also available with 8% or 10% lidocaine included. A cream that excludes benzocaine but includes lidocaine 23% and tetracaine 7% can also be compounded.
The total strength of a skin numbing cream can be determined by adding up the percentages of each ingredient. For example, EMLA is considered a 5% cream while BLT (benzocaine 20%, lidocaine 6%, and tetracaine 4%) is a 30% cream. A lower-strength numbing cream can be purchased online without a prescription, but this is usually not enough to completely numb the skin before a procedure.
How BLT cream is applied
Most patients receiving a skin treatment at a dermatology office or med spa will be having it on their face. The face is where aged skin is most visible and where a treatment can have the greatest impact on an individual’s appearance. The first step will be to thoroughly cleanse the face then pat it dry with a towel. The cream should then be applied while wearing gloves. A healthcare provider will always wear gloves when they are performing a procedure. However, if a patient is directed on how to apply a cream themselves, they should be advised to wear gloves to prevent numbing of the hands.
Note: Some sources have stated that using cling-wrap can increase the effectiveness of numbing cream. This method, called occlusion, should never be used by patients. This technique is dangerous as it can increase anesthetic ingredients to toxic levels in the body. In addition, it is simply not necessary with a high-strength numbing cream that will work effectively on its own. If occlusion is going to be used to increase the rate of onset it should only be done by an experienced healthcare provider.
The cream should be applied in a thin layer to the particular area being treated or the entire face if needed for the procedure. The anesthetic ingredients should start to work quickly, but the cream may be left on for 15-20 minutes to achieve the greatest effect. The cream should be wiped off completely before starting the procedure and the skin cleansed with rubbing alcohol. This is essential as the numbing cream should not be allowed to enter broken skin that may result from the procedure.
The total surface area that the cream is applied to is also a major consideration. If a treatment needs to be done to the entire leg, for example, BLT cream should not be applied to the entire leg at once. Applying topical anesthetic to a large surface area can result in toxic levels in the blood.
Healthcare providers and BLT cream
In most cases, BLT cream should be administered by a trained skincare professional and not a patient. There are multiple considerations when applying a numbing cream that only a healthcare provider will be able to determine. For example, the ingredients in BLT cream may interact with other skincare ingredients like benzoyl peroxide, which is frequently used to treat acne. Benzoyl peroxide can decrease the effectiveness of topically applied anesthetics. How BLT cream is administered matters as the amount used and the time the cream is left on can both affect outcomes. Topical anesthetics are generally safe when used correctly. A professional who uses topical anesthetics on a regular basis is better able to understand how to use them safely and effectively.
“Topical Anesthetics for Dermatologic Procedures” – Dermatologic Surgery