As a quick aside, how did the black widow spider get its name?  The female black widow spider was reported to [...]]]>

Image from Wikipedia user Trachemys

With a bold bright red hourglass on its belly against a shiny black background, the black widow spider is all business.  Thus, when the black widow spider attacks… well, you better hope it doesn’t!

As a quick aside, how did the black widow spider get its name?  The female black widow spider was reported to eat its male mate after mating.  In reality, it does not always do this.

When folks think of spider bites, they often imagine deadly spider bites.  In reality, the majority of spider bites are not life threatening.  However, the black widow spider bite is one of the more serious spider bites.

The black widow spider, also formidably known as Latrodectus mactans, can release a toxin called alpha-latrotoxin.  This causes your nerve cells (aka neurons) to depolarize.  Bites can lead to pain and swelling at the site of the bite but also fever, chills, nausea, vomiting, muscle pain, cramps, spasms and abdominal pain.  Needless to say, these are indications to get medical help.

People often come into the clinic worried about spider bites.  While the majority of these concerns turn out not to be spider bites, it does raise the question of what sorts of medical conditions spiders can cause.  In the United States, tarantulas (shown on the left) are one type of spider that may be found [...]]]>

People often come into the clinic worried about spider bites.  While the majority of these concerns turn out not to be spider bites, it does raise the question of what sorts of medical conditions spiders can cause.  In the United States, tarantulas (shown on the left) are one type of spider that may be found in the wild and as pets.  While tarantulas can bite, a more common form of defense is for the tarantula to throw its hairs at a predator (e.g. at you if it thinks you’re going to attack it!)  These hairs have little barbs and are urticating, meaning they can cause urticaria (a fancy word for hives or wheals).

These little barbed hairs can lodge in the skin and cause wheals or, they can also lodge into the eye.  When they lodge in the eye, these tarantula hairs cause a condition called ophthalmia nodosa.  These barbs in the eye cause the eye to get inflamed and could actually lead to vision loss if severe enough.

Needless to say, if you believe you’ve been attacked by a tarantula, you should probably get checked out.  More on other spiders (e.g. black widow, brown recluse, etc.) in future posts.

Depending on your baseline skin type, you  may have noticed that after being out [...]]]> In a continuation on the theme of ultraviolet (UV) light, we answer the question of how UV light causes tanning or darkening of our skin.   The answer is that there are multiple methods by which tanning occurs.

Depending on your baseline skin type, you  may have noticed that after being out in the sun, your skin becomes tanned or darker (if you’re very fair-skinned, you may not tan at all, but rather, just burn).  You may have noticed this change in your skin tone hours after your sun exposure, or perhaps days after.

Tanning/darkening occurs via two methods and thus can occur immediately as well as in a delayed form.

1) In immediate tanning, the darkening occurs hours after the exposure to ultraviolet light.  The trigger is ultraviolet-A (UVA) light.  The melanin (pigment giving our skin color) which is already sitting around in your skin cells becomes oxidized.  Melanosomes (which are sacs of melanin in our cells) also get redistributed.  These effects occur relatively quickly and the tan can be seen within hours.  Note that in this form of tanning, there is no protective effect against additional UV exposure.

2) In delayed tanning, new melanin is made by your cells in a process called melanogenesis.  Since it takes time for your cells to make melanin, the tan is not evident until 48-72 hours after exposure.  This process is triggered by ultraviolet-B (UVB) light.

Need a review on the difference between UVA and UVB and wavelengths of light? See the previous DermBytes post on this topic.

So what is this practice of cupping? (Does it [...]]]>

Photo from Wikipedia, author Alanna Ralph

Growing up, my mom had told me the story of a kid whose parents practiced cupping on him.  Turns out that bruises which were left behind from the cuping and these bruises were noticed at school.  The parents were called in to investigate potential child abuse!

So what is this practice of cupping? (Does it involve a cup?)

Cupping is an alternative medicine practice most commonly seen in Eastern Asian countries such as China.  Suction via “cups” placed on certain areas (often the back) is thought to mobilize important components such as blood in the body.  Sometimes, this suction is created via a pump, and other times by heating the air in the cup before placement onto the body.  (Remember from middle school and high school that as a gas cools, it compresses, so then you get suction.)  The cups are then removed after a period of time.  Sometimes, bruising is left behind but not always.

I’ve actually tried this cupping procedure before where the cups were heated before placement.  They did feel hot when placed, but then cooled down.  I could feel the skin being sucked into the cups.  All in all, it was not terribly uncomfortable.

I’m curious, how many of you have heard of cupping, had cupping, or have had friends who have had cupping?

First, the idea of putting a lit candle anywhere near the face let alone inside the ear seems a little scary to [...]]]>

Ear candling. Debris accumulates from the lighting of the candle.

Years ago, a relative of mine introduced me to the practice known as ear candling.  I didn’t have it tried on myself, but she was keen on trying it on an elder relative.

First, the idea of putting a lit candle anywhere near the face let alone inside the ear seems a little scary to me.  As it should to you too.  This practice is one that is practiced by people with the hope of improving health and sometimes to remove ear wax.  However, it is likely ineffective for both.  A hollow wax candle or cylinder of waxed cloth is lit and the non-lit end is placed in the ear of the individual.  The ear being treated is facing upwards.  Often, the candle is placed through a paper plate with a hole cut in it in order to catch any dripping wax or ash.

Studies have not shown any health benefit and in fact, trauma to the ear has occurred during this procedure.  The debris that is thought to be from inside the ear is debris that gathers just from lighting of the candle (whether or not it is placed in the ear or not.)  So just as your doctor warns you again sticking a qtip into your ear, don’t go sticking a candle in your ear!