Several times each year someone asks in class about the relative danger of an envenomation from a small versus a large crotaline (aka pit viper).  Some people are insistent that smaller snakes are more dangerous.  This idea has always felt counterintuitive to me.  The explanations seem fanciful at best.  Usually, people argue that larger (and therefore older) snakes possess some sort of volume control.  They argue that larger snakes hold back venom against humans because we are not food for them.  These larger snakes want to warn us with a strike but preserve venom for when it matters, like a meal.   I have been unable to find any science and none of the experts that I have spoken with can give a definitive answer one way or the other.  With the publication of a recent study, perhaps this theory will disappear.

This past December the Annals of Emergency Medicine published an article by Herbert and Hayes (2009; Volume 54 #6: p 831) in which they argue that a protective layer of denim over the skin may help to decrease the severity of an envenomation from a defensive strike by a southern Pacific rattlesnake. (I leave you to view the details and decide for yourselves.)   In their study, after provoking a test snake, they presented it a latex glove filled with warm water, one time bare and another time covered with a denim glove.  After a bite, they measured the venom in the water within the latex glove and, when used, on the denim glove.  The order of the trials were randomized and occurred 2 weeks apart.  They found that the amounts of venom measured were consistently and significantly greater from the larger (greater than 66 cm in length) versus the smaller (less than 55cm) snakes.

In the discussion section, they point out the volume differences as well as information from other sources that argue against the smaller is more dangerous theory.  Included are the facts that larger snakes are more likely to strike and that their strikes are more accurate.  Large snakes have longer fangs with larger hollow spaces allowing for deeper penetration and more venom flow.   They cite references (that I did not check) that claim that larger snakes cause more serious envenomations.  Herbert and Hayes state:

Thus, the more effective antipredator deterrent of bites from larger snakes may explain why they resort to biting more readily than smaller snakes.

And maybe Homo sapiens don’t learn to stand back.

Bottom Line

Although the results from this study do not definitively answer the question about size it does lend some scientific basis for debunking an unfounded belief.  Practically, of course, it does not really matter.  The anticipated problem of a venomous snake bite is an envenomation.  There is no good way to predict beforehand who will be envenomated, and if so, how bad it will be.  We treat what we see.  By the way, some skin covering, like denim, seems better than none.


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Click to enlarge.

Somewhere deep in the woods near Camp Dandelion, future ‘s bring in the New Year on snowshoes.

, WMA lead instructor, sent in these submissions of ‘The Man’ surfing through the holidays on a family vacation.  Click on the pictures to enlarge.

Today is the last day to submit your photos for consideration. 3 $100 cash prizes are at stake. If you would like to submit your last minute entry, please email with your picture and a caption.

‘The Man’ has had quite a busy year! This submission comes from students of a at . Fred W. Symmes Chapel, an open chapel constructed in 1941, is also called “The Pretty Place” because of it’s spectacular views.

Congratulations to the students that received their on December 16, 2009!

Q:  I have noticed that some outdoor organizations are moving away from carrying injectable epinephrine into the field.  Would an antihistamine (e.g., Benadryl) work just as effectively to treat allergic reactions?  What do you think about the Benadryl strips?

Even though some people are reluctant to carry epinephrine (delivered via autoinjectors like Epipens or a syringe) into the field, it continues to be the treatment of choice for anaphylaxis, a life threatening allergic reactions involving multiple body systems.  Specialty groups in Australia, Canada, the UK and US, have published position statements emphasizing this point.  Even relatively conservative organizations, including the American Red Cross and the American Heart Association, have advocated for training lay providers in its administration.  And yet, fear abounds, but not for medical reasons.  The fear is based on presumed legal issues.  The reason and questionable logic for this position is a topic for another blog.

Antihistamines like diphenhydramine (e.g., Benadryl) are often an effective treatment for simple urticaria (aka hives, welts, whelps).  Although urticaria frequently accompany anaphylaxis, they are absent in nearly a quarter of the cases.  While an antihistamine may suppress the urticaria that can accompany anaphylaxis, they will not reverse the life-threatening upper airway, pulmonary or vascular manifestations.  To suggest otherwise is incorrect and potentially dangerous.  Plus, there are many non-allergic causes of urticaria.

Transmucosal (through mucus membranes in the nose and mouth) administration represents a major step forward for some medications.  This route is potentially a great alternative to pills and awful tasting syrups for kids.  Medications administered this way are also better tolerated by people with nausea and vomiting and could be absorbed more quickly.  I have no experience with the strips and could not easily find information on their pharmicokinetics.  One web suggested that they would also be helpful when a reaction occurs in the mouth.  I think that advice is of questionable value.  An allergic reaction in the mouth with swelling can result in difficulty swallowing.  That sounds like anaphylaxis to me.

Transcutaneous (through the skin) is another potentially useful method for medication administration.  It has been particularly valuable for medications that need to be released slowly over time, obviating pill schedules or the need for needles and expensive pumps.  Current formulations of diphenhydramine cream are meant for topical (surface only) and not transcutaneous use.  They are poorly absorbed through the skin and therefore do not have predictable or significant absorption.

Cost seems to be the biggest downside of the strips, about 1$US as opposed to less than 0.1$US for an equivalently dosed capsule of generic diphehydramine.

Bottom Line

If your friend’s reaction to tree nuts is predictably simple urticaria, isolated to the trunk or limbs, an antihistamine in any form (other than a cream) should be equally effective.  Why pay more for the strips if they are no better?  But remember, allergy related urticaria can progress to signs and symptoms suggestive of airway, lung or vascular involvement at any time.  If they do, think anaphylaxis; think epinephrine.

I still believe that properly trained people should have epinephrine available when they are traveling outside of easy access to EMS.  It becomes essential if you are traveling with anyone known to have allergies to substances that could be encountered on the trip.

Ted H., who is a successful graduate of a , submitted the two pictures below. Please click on the images to view them larger.

One picture is in Bayou Manchac and the other is in Alligator Bayou, which goes from Spanish Lake and feeds into Bayou Manchac.

Time is running out for the ‘Where’s the Man?’ competition. The deadline for submissions is December 31, 2009. Please email [email protected] a photo of yourself sporting your course t-shirt along with a caption to be considered for the 3 $100 cash prizes!

Q: Does provide authorization to administer medications in the field? I have my WFR training for my camp job.  My boss told me that because of state law I cannot administer any medications to our clients, not even over-the-counter items like antibacterial cream or ibuprofen.

There is no one set of laws that uniformly governs this kind of activity.  You should get the concepts clear in your mind.  You have been CERTIFIED (trained) to in an expanded scope of practice.  To use those skills in a workplace environment, within the constraints of state law, you need the AUTHORIZATION (approval) of your employer and the permission of you patient.  On the other hand, if you are on your own trip, we (WMA) believe that with the permission of your patient, in a wilderness setting, and after an accurate evaluation, the WFR-level care that you deliver is first aid.  If you have no duty to care and are not compensated, most states would view you as a good Good Samaritan.  We trust that it would be done competently and only to the level of your training.

If you are working for someone, you need to abide by what they recognize as the standard of care.  Do not do something that your employer has expressly forbade you to do.  There are still plenty of other important things that you have been trained to do.

for more information and to check out the articles written by our attorney, Rufus Brown, on this topic.

Reading “Goodnight Gorilla” in Bremen, ME. – , Lead Instructor

(Nothing exotic, but lots of fun!)

Submitted by Kelley Duffy /

Don’t forget! At the end of the year, we will select the 3 best submissions. The winners will receive $100 cash prize.  Send in a picture of yourself wearing your WMA course t-shirt to [email protected] in order to be eligible for the prizes.

This picture was taken by Michael’s 10 year old son while on vacation this summer at Grand Teton and Yellowstone.

Michael B.

Don’t forget! At the end of the year, we will select the 3 best submissions. The winners will receive $100 cash prize.  Send in a picture of yourself wearing your WMA course t-shirt to [email protected] in order to be eligible for the prizes.

Here’s the Man attending an all Jeep off road event on Drummond Island, Michigan, in June 2009.

Submitted by:
Micah Bell
NREMT-B, WEMT
National Park Service-Indiana Dunes N.L.

Don’t forget! At the end of the year, we will select the 3 best submissions. The winners will receive $100 cash prize.  Send in a picture of yourself wearing your WMA course t-shirt to [email protected] in order to be eligible for the prizes.