Expert: Dr Ian Jackson - please note UK based - 11/3/2011

Question
QUESTION: Since January of this year, every 4 to 6 weeks, myself and my girlfriend have been receiving electrolysis treatments - myself on my throat (between the collarbone and the jaw), and my girlfriend on her bikini area.

At first we tried to minimize discomfort using a readily available, over-the-counter topical anaesthetic - EMLA cream (2.5% lidocaine / 2.5 % prilocaine):

http://www.astrazeneca.ca/documents/ProductPortfolio/EMLA_CIL_en.pdf (page 5)

http://www.astrazeneca.ca/documents/ProductPortfolio/EMLA_PM_en.pdf

We saturated the treatment areas for 1-2 hours prior to treatment and although we did notice an effect, the effect was not very pronounced and seemed to only anesthetize the first couple millimeters of the skin surface.  For example, we wouldn't feel a finger touch or pin prick, but we certainly felt the pain from the electrolysis!  So, I'm not sure if it's a matter of pure efficacy, or a matter of depth of skin penetration, but we needed something more potent.

Upon advice from a compounding pharmacist, we received a
prescription for a 23% lidocaine / 7% tetracaine topical ointment (it has the texture and appearance of vaseline jelly).  All of the following treatments using the ointment from the first container of purchase were very successful from an experience point of view - virtually no pain at all for both of us!

However, in a puzzling sense of irony, now the ointment has been hardly effective at all, and seems to have equal or less effect than simple EMLA cream?!?!  We consulted with the pharmacist, and although he had no literature for reference, he suggested without confirmation that perhaps we have become sensitized to the cream? It would seem weird to become sensitized to the ingredients when we only receive treatment once every 4-6 weeks, no? Anyways, in a desperate attempt to rule out defective/expired ingredients or improper compounding techniques, we purchased the exact same ointment from a different pharmacy, but alas received the same failing results.  Upon discussion with the pharmacist, we also tried the same 23%/7% medication in a "lipoderm" beige, cream textured base with lousy results. We also tried a 23% lidocaine / 7% tetracaine / 2.5% prilocaine ointment and again, got lousy results.

At first we just "grinned and beared it" and selected more tolerable areas for treatment.  However, we're now getting to the point where there are no more tolerable areas to treat - we're getting to the ultrasensitive areas that have a 15 minute pain threshold window at best.  This wouldn't be a problem if we lived locally to the electrologist, but we drive ~300km (600km round
trip) to receive treatment and considering the price of fuel & car
maintenance, it doesn't make sense to spend 6 hours driving for a half hour of treatment.  In order to maximize the costs of commuting, our goal is to find something effective for a minimum of an hour's worth of treatment or more per person, up to a maximum of three hours. In addition, if it's safe (i say this knowing the touchy exposure limits of some anesthetics), seeing as there's two of us receiving treatment, we would entertain the idea of alternating hourly treatments between the two of us (I.E. A-B-A-B) in order to obtain more than an hour's worth of treatment if the duration of effect is only an hour.

So, in summary of my long babble above, short of injecting local anaesthetic (which i would gladly do if it were possible), what topical anaesthetic(s) and/or what concentrations would you suggest we try?  Feel free to list all options so we can maximize our time with our physician as we tend to have to book a month in advance or more to see him. If you require more information to provide advice, please let me know.

ANSWER: Hi there Daniel
You are correct that was a long preamble. Unfortunately local anaesthetic agents do not cross the skin barrier very well. In the UK the EMLA cream is still the most prevalent and none of these are available across the counter without a prescription. So I have no experience with the mix you are currently using. In reality the drug has to get across the skin barrier and then penetrate the nerve tissue to have its effect - this requires the drug to change its ionic form and so even though you are using a 23% lidocaine preparation the amount of free drug getting to where it is needed may be small.
It is strange that it has worked for you both at the start and I do not accept that your body is now sensitised to it and so can resist its effect. I suspect the only thing you can do is experiment with application times and techniques.
It may be that if you apply between 30-60 minutes before treatment then this would allow for maximal effect. Occlusive dressings to keep the gel in place over the skin may also help.
Bottom line is that I'm afraid you need to experiment with the tools you have as I am not aware of any other alternatives. You could also take 1 gram of paracetamol and 800mg of ibuprofen 1 hour before the treatment as well and that might help to a degree.
Sorry can't be more helpful.
Dr Ian Jackson

---------- FOLLOW-UP ----------

QUESTION: Hi Ian,

thanks for your wonderful response; i really appreciate it. I've been wanting the advice of an anesthesiologist rather than a physician.

Not that i doubt your judgement...i just wish to confirm that 800mg of ibuprofen is safe to take in one dose?

The reason i ask is that 400mg always seems to be the recommended dose on the packaging of ibuprofen/advil here....and i know i've had prescriptions in the past for 600mg ibuprofen and then upon the advice of a physician, simply buy over the counter varieties and take 3x200mg pills as 600mg seems to be the magic number for me whenever my back acts up whereas 400mg seems to never work.

Then again, the 800mg dose would be only once every 4-6 weeks...i'd imagine to take it with food? Ultimately as my gut is used to 600mg 2 or 3 times a day sometimes, i'm more concerned about the gut of my girlfriend.

Cheers,

Daniel

Answer
Hi Daniel
Over the counter medications often have dosage regimens well within the full possible dose that can be prescribed by a doctor. Do not take this as reason to up all doses of things you can buy!
You are correct that increasing the dose to 600mg makes it more effective.
However for ibuprofen we use single dose of 800mg in many situations e.g. the management of acute migraine atacks. So a one off dosing every few weeks would not be an issue.
Yes take it with food and one off doses should not have an adverse effect on your girlfriends gut.
Dr Ian Jackson