FDA Warns of Potential of Serious Side Effects with Topical Numbing Agentsand
By Todd Neale, Staff Writer, MedPage Today, Published: January 16, 2009
ROCKVILLE, Md., Jan. 16 -- The FDA has issued a second warning about the potential dangers of using topical anesthetics for relieving pain from medical tests and conditions.
The latest advisory was prompted by a report last summer on the results of a randomized trial evaluating the use of lidocaine for the pain and discomfort of mammography. (See: Pre-Mammography Painkiller May Ease the Pinch)
The researchers found that women using lidocaine -- which was spread over the breasts and chest wall and covered with plastic wrap for a total absorption time of about 45 minutes -- reported significantly less discomfort than those using acetaminophen, ibuprofen, or placebo.
"Although no serious side effects were reported in this study," the FDA warning read, "it was not large enough to evaluate whether uncommon but serious reactions could occur with this use.
"FDA remains concerned about the potential for topical anesthetics to cause serious and life-threatening adverse effects when applied to a large area of skin or when the area of application is covered," the advisory read.
The agency said that some of the topical medication can pass into the blood stream upon application.
Under certain circumstances -- if a large area of skin is covered, the drug is applied to broken skin, or skin temperature increases -- the amount of medication entering the blood stream may be toxic, causing irregular heartbeat, seizures, breathing difficulties, coma, and death, the agency said.
This latest warning repeats the concerns of an advisory issued in February 2007 following the deaths of two women, ages 22 and 25, who applied topical anesthetics to their legs and covered them in plastic wrap to numb the anticipated pain of laser hair removal.
Both women had seizures, fell into a coma, and subsequently died because of the drugs' toxic effects.
The drugs involved were lidocaine and tetracaine.
The FDA advised physicians to determine whether a topical anesthetic would create the necessary pain relief when considering its use for any purpose and whether an alternate treatment would be as effective.
If a topical anesthetic is determined to be the best choice, the agency recommended using the lowest amounts possible, applying the medications as sparingly as possible, avoiding broken or irritated skin, and being aware that wrapping or applying heat to the areas treated with the medications can increase the risk of serious side effects.
Breast Imaging Premedication to Reduce Discomfort during Screening Mammography1
Colleen K. Lambertz, MSN, MBA, FNP, Christopher J. Johnson, MPH, Paul G. Montgomery, MD, and James R. Maxwell, MD
1 From the St Luke's Mountain States Tumor Institute (C.K.L., P.G.M.), 100 E Idaho St, Boise, ID 83712; Cancer Data Registry of Idaho, Boise, Idaho (C.J.J.); and St Luke's Regional Medical Center, Boise, Idaho (J.R.M.). Received August 27, 2007; revision requested November 1; final revision received November 29; accepted January 24, 2008; final revision accepted March 4. Supported by the Mountain States Tumor Medical Research Institute grant. Address correspondence to C.K.L. (e-mail: lambertc{at}slrmc.org).
Purpose: To test the hypothesis that premedication with acetaminophen, ibuprofen, and/or 4% lidocaine gel would decrease discomfort and improve satisfaction with screening mammography in women who expect a higher level of discomfort.
Materials and Methods: In this HIPAA-compliant, institutional review board–approved, prospective, double-blinded, placebo-controlled clinical trial, 418 women aged 32–89 years who expected substantial discomfort with screening mammography were randomly divided to receive premedication with acetaminophen, ibuprofen, and/or 4% lidocaine gel. Subjects provided informed written consent. The primary outcome was discomfort. Secondary outcomes were satisfaction and plans for future mammography on the basis of discomfort. Subjects completed structured questionnaires with visual analog scales to measure discomfort and satisfaction. A generalized linear mixed-models framework was used to assess the effect of medications on discomfort during mammography, and satisfaction with technologist and machine combinations was included as a random effect. The "plans for mammography next year" outcome was modeled by using a binary distribution and logit link function.
Results: Discomfort was significantly lower in the lidocaine gel group (P = .01). Satisfaction was significantly negatively correlated with discomfort (P < .001). Satisfaction and whether or not the subject had delayed her mammography because of fear of discomfort had significant effects on plans to undergo mammography next year (P < .001 for both). There were significant differences in discomfort between different combinations of technologists and machines.
Conclusion: Premedication with 4% lidocaine gel significantly reduced discomfort during screening mammography, and reduced discomfort may improve the likelihood of future mammographic screening and early detection of breast cancer.
(Radiology 2008;248:765-772.)© RSNA, 2008
Originally posted 9/5/08, Our new paper is linked with facts you do want to know.
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Each year, about 800,000 women around the world are diagnosed with early breast cancer.
It amazes me that there is so much closed minded "research" aiming at co-opting women to believe that mammogram or other radiation exposure is good for them to detect cancer earlier and better.
The fact is that tumours picked up on mammogram are at least 8-10 years old. If you are 40 and get a mammogram (x-ray) every year, the risk of your getting cancer rises exponentially. Why aren't you being told this?
Other less intrusive and decidedly less risky diagnostic techniques have been around for a long time. Ultrasound is one, but that still relies on EMF or radio waves, but it is a far sight safer than X-RAY.
Another health impact that seems to be overlooked in this allegedly novel approach is that radioactive "tracers" or dyes are in use. Often there is no pre-test screening to determine if you have an allergy to the substance. These allergies may elicit anaphylactic reactions and death. Other considerations is the impact of radioactive substances on your endocrine system, especially your thyroid gland.
Mammography does not save or extend lives and is not a justifiable practice. So how much money do insurance companies and consumers pay out for radiation treatment of breast cancer? This practice results in only a less than 1% chance of improving survival. Is this worth such a large investment when so many medical claims are denied and there is virtually zero coverage of preventive practices? from the Lancet 2000; 355: 129-134.
and versus MBI
One drawback of MBI: It uses about 8 to 10 times the radiation of mammograms, a dose that engineers like Hruska are trying to lower with newer technology. Other medical centers also are testing MBI.
and they are again experimenting with an unproven technology that may be exciting to the researchers, but harmful to your health as there are no long term studies. Once again the lab rats are lining up to be experimented on, and paying to do so.
And by the way, don't overlook the fact that it is you that become the lab rat in this an in many other mainstream medical situations.
Thermography is really your better bet. Stand up for your health and demand this test.
Study: New way to spot breast cancer shows promise
By MARILYNN MARCHIONE, AP Medical Writer
Wed Sep 3, 2008
A radioactive tracer that "lights up" cancer hiding inside dense breasts showed promise in its first big test against mammograms, revealing more tumors and giving fewer false alarms, doctors reported Wednesday.
The experimental method — molecular breast imaging, or MBI — would not replace mammograms for women at average risk of the disease.
But it might become an additional tool for higher risk women with a lot of dense tissue that makes tumors hard to spot on mammograms, and it could be done at less cost than an MRI, or magnetic resonance imaging. About one-fourth of women 40 and older have dense breasts.
"MBI is a promising technology" that is already in advanced testing, said Carrie Hruska, a biomedical engineer at the Mayo Clinic in Rochester, Minn., which has been working on it for six years.
She gave results in a telephone news briefing Wednesday and will present them later this week at an American Society of Clinical Oncology conference in Washington, D.C.
Mammograms — a type of X-ray — are the chief way now to check for breast cancer. MBI uses radiation, too, but in a different way. Women are given an intravenous dose of a short-acting tracer that is absorbed more by abnormal cells than healthy ones. Special cameras collect the "glow" these cells give off, and doctors look at the picture to spot tumors.
Researchers tried both methods, on 940 women who had dense breasts and a high risk of cancer because of family history, bad genes or other reasons.
Thirteen tumors were found in 12 women — eight by MBI alone, one by mammography alone, two by both methods and two by neither. (The two missed cancers were found on subsequent annual mammograms, physical exams or other imaging tests.)
Looked at another way, MBI found 10 out of 13 tumors, missing three; mammograms detected three out of 13 tumors and missed 10. Using both methods, 11 out of 13 tumors would have been detected.
"These images are quite striking. You can see how the cancers would be hidden on the mammograms," Hruska said.
Mammograms gave false alarms — led doctors to conclude that cancer was present when it was not — in about 9 percent of patients, compared to only 7 percent for MBI. The MBI tests led to more biopsies than mammograms did, but they more often revealed cancer.
The Susan G. Komen for the Cure foundation and Bristol-Myers Squibb, which makes the imaging agent used in the study, paid for the work.
The next test will be to see how MBI stacks up against MRI. The federal government is paying for a new study Mayo is leading that compares the two in 120 high-risk women with dense breasts.
MRI is often used now for women with dense breasts, but it gives many false alarms that lead to unnecessary biopsies. Doctors hope MBI will prove more accurate and cost less — under $500 versus more than $1,000 for an MRI.
"We all know that mammography is, in and of itself, an imperfect tool, and we clearly need to do better in the future," said Dr. Eric Winer of the Dana-Farber Cancer Center in Boston, a spokesman for the oncology group. "It is fair to say that MRI will not solve all problems either."
One drawback of MBI: It uses about 8 to 10 times the radiation of mammograms, a dose that engineers like Hruska are trying to lower with newer technology. Other medical centers also are testing MBI.
"We're just beginning to see what this technology can do," she said.
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On the Net:
Cancer conference: http://www.asco.org and http://www.cancer.net
Mayo Clinic: http://tinyurl.com/5rrwx3
Copyright © 2008 The Associated Press.
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