Unless you're a healthcare professional, you probably are not aware of the serotonin syndrome. Pharmacists in particularly familiar with the syndrome and screen patient medication profiles for potential occurences. Serotonin is a naturally occuring substance responsible for signaling between neurons or generating impulses that travel thoughout the nervous system. Serotonin is involved in processes such as gastrointestinal motility, uterine contractions, bronchocontriction and thermoregulation to name a few.
Many drugs such as antidepressants work by increasing the availability of serotonin within the brain and nervous system. This can become problematic when one or more drugs that cause increases in serotonin are taken together. Excessive increases in serotonin can lead to unwanted adverse reactions such as agitation, tremor, muscle rigidity, hyperthermia, flushed skin and excessive sweating.
In rare or more severe cases, the syndrome can actually be life-threatening. Drug classes implicated in this syndrome include antidepressants (e.g. fluoxetine, paroxetine, venlafaxine), analgesics (e.g. meperidine, tramadol, fentanyl), lithium, cough preparations containing dextromethorphan (e.g. Benylin DM), and St John's wort. The elderly are particularly more prone to this syndrome if dosages are not adjusted accordingly. Fortunately, the condition and its symptoms are easily managed by discontinuing the involved medications. The syndrome can also be reversed with antidotes (e.g. cyproheptadine).
Granulosis rubra nasi. The medical term for an excessive sweating condition limited to the central part of the face, particularly the tip of the nose. As such, it is also referred to as 'hyperhidrosis of the nose'. It is also characterized by skin redness over the nose, cheeks, chin and upper lip. It's an inherited condition that more frequently appears in children (as early as 10 months of age) but can also be seen in adults. There are no statistics related to its prevalence but we do know that it is a relatively rare sweating disorder.
| |Thankfully the condition usually resolves at puberty, but is some cases, it can last into adulthood. In many individuals, hyperhidrosis of the palms and soles is also present. Granulosis rubra nasi can be confused with other conditions such a s lupus erythematosus and rosecea, so it is important to consult a healthcare professional to confirm the correct condition. | |
A typical case of granulosis rubra nasi. Its incidence peaks between the ages of 7 to12 and usually resolves at puberty
This Summer, my son and I travelled through some of the world's hottest areas including the Mojave Desert, Death Valley and Yosemite National Park. While the latter isn't necessarily known for heat, we did come across one of California's largest ever forest fires. The infamous Rim Fire is estimated to burn for about one month and has spread to about 250,000 acres (as of 6sep13) of forest. While we did get close enough to take some video, we actually didn't feel the intensity of the fire. Nonetheless, you don't need much imagination to know fires of that magnitude have to be generating an awful lot of heat. While my son is in his teens, I couldn't help but think how children do not deal with heat in the same manner as adults do. And so, I thought this could certainly be a topic for the Sweating Matters blog upon my return back home.
| |It appears that children (pre-puberty) are not as well equiped as adults to deal with heat. As such, they are more prone to 'overheating'. There are several reasons for this: 1) their sweat glands have not matured and are not as efficient as their adult counterparts 2) they have a higher surface area to body mass ratio ans as a result they tend to warm up faster when exposed to environmental heat and 3) under stress and/or activity, their hormone system is not fully developed and, as such, their sweat glands are not receiving as many signals to perspire. | |
Actual video of the Rim Fire taken just outside Yosemite National Park (August 21, 2013)
To compensate, particularly during play, children will deflect more of their carciac output towards the surface of the skin. In other words, their skin surface blood vessels will dilate and allow greater blood circulation near the surface. Because heat energy always moves to cooler areas, heat from the blood will dissipate towards the skin which is in contact with the cooler outdoors. A study in the early 1980's demonstrated that skin temperature in children is higher than adults when subjected to activity under identical environmental conditions. And so, children cool off more by a process of convection than evaporation or sweating.
Interestingly enough, another study has demonstrated that kids need 30% more energy than adults to perform the same activities. This in turn increases their metabolic rate and results in higher heat gains from muscular activity.
The bottom line is that children are more prone to hyperthermia during activity. Their ability to maintain a normal core temperature in jeopardized due to immature sweat glands. It is therefore important to keep our kids well hydrated during activity, especially in sunny, hot and humid conditions.
Finally, the chart at the right provides an indication of climatic zones and their relative safety with respect to activity and the risk of hyperthermia. Of course the higher the temperature and humidity, the greater the risk and need for precautions such as hydration and rest periods.
Heat stress and children - AAP Recommendations
Climatic security zones as they relate to activity and heat stress in children. Regardless of humidity index, temperatures over 29C or 84F are considered to be relatively dangerous.
Temperatures over 27C (80F) are particularly troublesome as even low rates of humidity give rise to 'alert' or 'danger' zones. For more details on climate, heat stress in children and recommendations from the American Academy of Pediatrics click on sun icon.
Gomes LH et al Rev Paul Pediatr 2013
What does proteins have to do with excessive sweating? Good question, and as it turns out, they are at the heart of the sweating process. Let's start with a quick little lesson about how proteins are made. Keep in mind there are thousands of different types of proteins and enzymes in our body. All are different in structure and all have different and often vital and life sustaining roles. Insulin is a good example of an extremely important protein.
Protein synthesis is a complicated process and a lot can go wrong (for example, DNA mutations can give rise to faulty proteins or enzymes - many diseases result from this). But let me simplify the process and keep referring to the diagram below as we go through the steps. The key player in the synthesis of proteins is DNA. A specific section (or gene) of the DNA molecule (keep in mind this is a huge molecule) is copied and gives rise to a smaller molecule called mRNA. This newly formed mRNA contains the specific code for the protein that is going to be synthesized. This code is recognized by units called tRNA. Each tRNA carries an amino acid (amino acids are the protein building blocks). The amino acid carrying tRNA units attach to specific areas of the mRNA (code subunits) and leave behind an amino acid as it detaches itself from the mRNA code subunits. In turn, the amino acids attach to one another to form a chain of amino acids (also called a polypeptide). This long chain eventually gives rise to a protein once the process is terminated. That's it!
As the name implies, these proteins function as water pores or channels across cell membranes. This allows water to be shunted from the cells' interior to their exterior. As such, clear cells and the aquaporin proteins are thought to play a key role in the production of sweat. Proteins also play a role in the duct section of sweat glands by reabsorbing electrolytes such a sodium. These so called 'sodium pumps' are responsible for the desalinating of sweat as it travels to the surface of the gland.
| || |Having said this, individuals with hyperhidrosis may have overactive or a large number of aquaporin proteins in the clear cells of their sweat glands. Here is the really interesting part of this story: what if we were able to develop a drug that was able to block the aquaporin protein. In theory this would put the brakes on excessive sweating. Hyperhidrosis could be controlled using different doses of this drug, just like a lot of other medical conditions. And so, research into this area of science continues.....
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It's the month of August and we are on vacation...only from our Sweating Matters blog that is. Everything else is business as usual. Thanks for your continued support and we look forward to resuming our blog in September. See you then!
If you have never heard of the humidex or not sure what it is, you are probably not alone. If you think it's something that has to do with the weather, you're right. The humidex is a shorter term used to express the 'humidity index'. It's a Canadian innovation first introduced in 1965. The humidex gives a better sense of just how hot is really is or how unconfortable it might be. For example, the temperature might be 32°C (or almost 90°F) and the humidex is 40. In other words, because of the ambient humidity, the 32 feels like a dry 40 degrees celsius (104°F).
| |The index is based on a calculation of heat and humidity by using current air temperature and the dew point (the temperature and barometric pressure at which water vapour condenses into liquid). This is an important consideration, particularly for those of us with an excessive sweating condition. The skin has a significantly more difficult time ridding itself of sweat under moist or humid conditions. And so, when it's humid your skin will more likely remain wet, hence the discomfort. Given that the evaporation of sweat from our skin helps to cool off our body, it is particularly worrisome when humidity inhibits this process. As such, the core temperature of our body can remain high. | |
Humidity acts as a barrier to the evaporation of sweat from the surface of our skin. This in turn inhibits our body from cooling off. As such, our internal temperature can remain dangerously high.
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When the humidex reaches 40 to 45, Environment Canada recommends avoiding exertion. Above 45 is considered dangerous and predisposes individuals to the risk of heatstroke. The winter time equvalent to the humidex is 'wind chill'. Ironically, this measurement was invented in the US, where winters tend to be milder than those above the 49th parallel.
The Sweating Matters blog takes a break for the month of August but resumes in September. Thanks for your continued support and we welcome any comments.
The mobile health (mHealth) market is growing and getting a lot of attention. And there are a lot of reasons for this. It's a large market and there is a lot of demand. More than ever, individuals are thirsty for medical knowledge. There are about 97,000 apps related to health and fitness and over 300,000 downloads paid on a daily basis*. There's a lot at stake and the number of potential applications is huge. Five years from now, the mHealth market is expected to reach over 3.4 billion smartphones and tablets. By 2017, this market is expected to reach revenues in the order of $26 billion US*.
From an economic and practical perspective, health related apps may help reduce healthcare costs and increase the availability of some aspects of healthcare.
While about 15% of medical apps are for healthcare professionals, the majority of mHealth applications are targeted to consumers
This, in turn, helps to indicate to users the proper time to hydrate during physical exercise. According to the researchers this will also help to avoid the risk of developing muscle cramps during a training session.
| |A team of researchers from Cornell University is busy developing a smartphone that will detect pH (the scale used to measure the acidity of a substance) in saliva and sweat. Salivary pH is correlated to enamel decalcification or the acidic breakdown of calcium in the teeth. Similarly, sweat pH is correlated to the amount or concentration of sodium as well as sweat rate. Allow me for a moment to go out on a limb. I think this is just the beginning of sweat related smartphone applications. Given that sweat contains substances like biomarkers and the fact that we can use sweat to detect exposure to alcohol, its not a stretch to think there will come a time that we have access to a variety of smartphone applications related to sweat. Forget the breathalizer test. Just swipe a plastic strip on your forehead or underarm and stick it into your smartphone. * research2guidance
| |If you have been following our blogs, you are probably aware that sweat glands do more than just sweat. To a certain extent, its name does it a disservice as more evidence points to a variety of roles played by these tiny subdermal structures. Most of our readers are equally aware that eccrine sweat glands are vital in controlling our internal body temperature. We also learned that sweat glands do not only respond to thermal factors but to non-thermal signals such as body fluid pressure (or volume) and contracting muscles (April 2013 blog). More recently (June 2013 blog), research has demonstrated that sweat glands played a major role in human evolution, and perhaps, may have contributed to the development of a brain larger than some of our related homonid species. | |
Keratinocytes and gland cells migrate towards the surface of the skin (red arrows) and play a ritical role in the repair of wounds
Just when I thought these tiny sweat factories had played out all of their roles, new insights in the process of wound healing have emerged once again implicated the importance of sweat glands. Skin specialist from the University of Michigan have recently uncovered that sweat glands help heal scrapes, burns and ulcers. For some time now, traditional thinking dictated that wound healing started by the proliferation of skin cells or keratinocytes (pronounced: care-a-tino-sites). The process of generating skin cells originating from hair follicles and from the wound's edges.
The human stem cell is a cell that has not differentiated itself. Depending on its environment and a number of other factors it will become a specific type of cell as seen above.
| |The new discovery suggests that skin cells also originate from the base of the injury where sweat glands act as a reservoir of stem cells. These so called stem cells are a type of cell that, with a few alterations, become skin cells. In fact, stem cells are also called multipotential cells because, depending on the alteration, have the potential to differentiate into a number of different types of cells.
Researchers believe this opens the door for possible new therapies that would be targeted at sweat glands in efforts to help wounds repair more rapidly. This is of particular importance in individuals that suffer from ulcers and life-threatening burns which are prone to infection.
In my next post, we talk about a sweating application on smartphones...believe it or not. Stay tuned!
| |There are certain physiological mechanisms or body processes that we have acquired thanks to the lifestyles our very, very distant ancestors. For example, the colouring of our skin is a process that is dictated by the amount of melanin that is released and by the number of melanocytes (melanin producing cells) found near the surface of our skin. The process of producing melanin evolved over the millenia in response to exposure to sunlight. Today, we have strong evidence to demonstrate that humans began their journey some 60,000 years ago out of Sub-Saharan Africa region. This is a tropical region that is hot and very sunny. As humans began to shed body hair due to warm climates, our skin became exposed to sunlight. | |
National Geographic and IBM partnered a few years ago to create the Genographic project. You can actually send in a DNA sample and they determine the origin of your ancestry to many thousands of year ago.
And so, a mechanism evolved to protect our skin (our eyes too) and DNA bearing cells from the dangerous ultraviolet rays emanating from the sun. Melanocytes responded by producing melanin, a skin pigment that absorbs ultraviolet rays within a certain range of wavelengths. Today, we see some individuals taking advantage of this process in efforts to give themselves a “healthy-looking" tan.
Uv light can actually break the molecular DNA strands. Thank God we have mechanisms that can repair the damage. But sometimes the damage is too severe and remains irreversible
There are some individuals who develop premature skin damage and a certain proportion develop lesions and melanomas due to damage to the DNA within skin cells. When UV light damages DNA, many vital cellular processes (e.g. making of critically important proteins and enzymes) go awry and cells lose their capacity to function and replicate normally. Depending on the nature and severity of the damage, skin lesions can be pre-cancerous or become cancerous. Those of us with light skin tend to have lineage from regions further from the equator, where the response to sunlight has deminished through the generations.
Another evolutionary process we are all too familiar with is sweating. Similar to the development of melanocytes, humans developed sweat glands and the ability to sweat. This process evolved in response to regulate the inner body temperature that often would increase as a result of living within the tropical regions of the world. The mechanism also provided humans the ability to be active (e.g. hunting and gathering) for long periods of time, knowing that our body could regulate its temperature back to normal quickly and effectively. One of our close relatives (anthropologically speaking of course), the chimpanzee, can only run a few hundred yards before he becomes exhausted. The reason being that the chimp doesn't have the extensive network of sweat glands that we do. As such, our furry relative can't lose body heat fast enough to allow for continuous physical exertion.
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What’s equally interesting is recent research from Pennsylvania State University that demonstrates that sweating may be responsible for providing humans with larger brains - another attribute that sets us well apart from our 'chimpy' friend.
Being particularly sensitive to higher temperatures, the brain requires a relatively cool supply of blood to allow it to prosper. This can only be achieved through the advent of an efficient cooling mechanism. By maintaining a relatively cool environment, the brain was able to physiologically develop into a larger organ. Of course, like all other evolutionary processes, this certainly did not happen overnight.
And so, what is often regarded as a nuisance, sweating is a critical mechanism that evolved not only to regulate inner body temperature but also to allow the human species to expand the size of its brain. I suppose it would be fair to say that sweating is another example of things not always being what they appear to be from the outside.
| |If you are familiar with gustatory sweating you know certain foods have a greater tendency to exacerbate the the sweating associated with this condition. If you are a woman going through menopause, chances are you actually experienced hot flushes and night sweats. The latter are collectively referred to as vasomotor menopausal symptoms. Because hormones such as estrogen begin to decrease during menopause, there are a variety of changes and symptoms that result. | |
The Mediterranean diet includes foods such as fish, olive oil, legumes, vegetables, fruit, and nuts.
Now it appears that certain foods are more likely to intensify nights sweats. A large Australian study has demonstrated that certain foods will make your nights less comfortable. The study looked at whether specific dietary patterns including the Mediterranean diet, cooked vegetables, fruit, meat and processed meat, dairy, and high fat and sugar were associated with an increase risk of having night sweats and hot flushes. The study followed over 6000 women during a 9-year period.
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It turns out the high fat and sugar diet was most likely to be associated with vasomotor symptoms. The more favourable dietary patterns included the Mediterranean-style diet and high fruit consumption. Good news considering a diet high in fat and sugar isn't good in the first place. If you are menopausal and are going through night sweats and hot flushes, give your diet some thought. Just cutting back on the high fat and high sugar foods of your diet may make you sleep a little better at night.