Dangers of Topical Anesthetic for Laser Resurfacing?

The risks of topical anesthetic toxicity are known to correlate with the larger surface area of involvement. Facial areas are small so with laser resurfacing the treatment is safer than if someone were to apply the anesthetic cream to a very widespread body area(s) as may occur with laser hair removal. New guidelines are recommended by the pharmaceutical companies in limiting the surface area of application.

Every medication has a proper dose.  Topical creams for laser resurfacing of the face are absorbed by the skin, however, in most cases the amount is less than your threshold tolerance.  Speak to your doctor about the cream he or she uses to assess your risks. 

Thank you for your question. We use topical numbing cream on the face, but not on the lower legs or back due to the surface area and absorption of the large area.  In small areas, the cream is very safe.  Using saran wrap over the whole legs, could be life threatening and there have been reported deaths. Be certain to be under the supervision of a board certified dermatologist or plastic surgeon with expertise in laser surgery for the most effective and safe treatments.   I hope this helps.

The major risk with using compounded products for topical anesthesia remains a concern many patients have. The balance of getting sufficient anesthesia without risking absorption overdose remains the challenge with these products. Here are a few tips I think will help:

 

1. Ask your physician about what is in the cream and the percentages. Most topical agents for facial lasers have concentrations of lidocaine and tetracaine under 10%. If their product has higher percentages, make sure you get some explanation on their philosophy for using such higher concentrations. Also, some lasers and devices hurt more than others, and the clinic should use coentrations anticipating the expected device pain and discomfort.  

 

2. Ask your physician about the phamracy compounding the agent and the suggested storeage/expiration date. In many communities, there are some compounding pharmacies that generally do a higher volume of business in this space, and thus their compounds are more well known in the local community. There are also national compounders that make topical creams for lasers. Often the storeage instructions and expirations dates are clear, and these products have less effectiveness if they are expired or improperly stored. Also be aware that the FDA regulations for these products are different than traditional pharmaceuticals.

 

3. Be aware of the surface area of your body getting the creams. In general, the front of the face represents a surface area of the body that is under 5% of total body surface area.. For this reason, the application of topicals on the face for lasers is very safe. However, if you have a lower BMI and the cream is repeatedly applied, risks can increase. Also occlusion of the product can increase its absorption and thus increase both efficacy and risk.

 

4. Make sure you ask your doctor about their experience performing small nerve blocks. Often times, good nerve blocks can reduce the need for exessive topical concentrations for extended periods of time.

 

5. Finally, be aware that the cleaner the skin, the more effectively and efficiently the topical will be absorbed. Make sure your face is washed before the topicla is applied. Some offices will clean the face with acetone or alcohol to make sure the surface is clean, optimizing the efficacy of the cream.

Topical anesthesia can help with comfort during laser resurfacing.  The important safety concept is to not expose too much of your skin surface to the medication and risk absorption to the point of toxic levels.  For facial treatments I have not heard of cases that have had this issue.  The areas that I have heard of problems was for large surface regions like the legs.  In conjunction with a large surface, another risky issue is the use of occlusive wraps to get better numbing effect.