The People's Guide To Mexico

Staying Healthy
Crocodile: Herbal Bug Discouragant
Bounce Away the Bugs

Staying Healthy (homepage)

Pennyroyal Oil:

Protection from No-see-ums?

People’s Guide Correspondent David Eidell recently visited San Blas, Mexico on a daring assignment to test Lorena’s homebrew ‘bug dope’.

Lorena says: “I happened to mention to David that I add 20-to-30 drops of pennyroyal oil to a small container (about 2 ounces) of off-the-shelf insect repellent (Australian “Green Ban” is my favorite). This pennyroyal oil combination is very effective against no-see-ums and it also smells better than DEET, the standard chemical brew used to repel mosquitos.”

As our token sceptic, David immediately challenged Lorena with, “Pennyroyal oil versus no-see-ums? You gotta be nuts! Right?” He later modified this statement, however, and offered to give Lorena’s concoction a try on his next trip to San Blas, a small beach town long rumored to be the no-see-um capital of Mexico.


In a demonstration of pure faith (but little common sense), I am going to offer my flesh and blood for the benefit of humanity and the knowledge of science. The purpose? To positively determine if Lorena Havens’ alchemy actually works as claimed.

The subject is “Bug Repellent”

I'm going to run a dangerous experiment to prove (or disprove) Lorena's claim that a few drops of pennyroyal added to standard mosquito repellent, will serve as an effective barrier to jejenes (no-see-ums). Jejenes, you will recall, are the most voracious flesh eaters on the North American continent. I have been devoured by jejenes in past visits to certain Mexican beaches, even during the winter months! In fact, in February, 1993, also in San Blas, those little jejenes had their fill (I was covered with DEET) and caused me three days of torment with swollen, itching bites.

This is how I intend to conduct my test: I have purchased a bottle of 55% DEET lotion, of reputable manufacture. I have also purchased a small vial of PENNYROYAL HERB EXTRACT (Hedeoma pulegioides) in a 1 fl. oz. bottle, complete with eyedropper.

I will slather on a good coat of 55% DEET all over my exposed body and, additionally, I shall mix about three drops of Pennyroyal per arm, four drops of Pennyroyal per leg and another three drops for face, neck and head. Each droplet will be placed in strategic fashion, separate from the others, and will be rubbed in to assure as thorough a blending as feasible.

I will stroll along a Pacific beach for one hour. The test will commence one half-hour before sundown and terminate one half-hour after sunset. The timing for this test will be the last week in July, 1994. The place shall be San Blas, Nayarit.

In my thirty years of travel in Mexico, I cannot conceive of a test more severe than the one I have outlined above.

If Lorena’s mixture works, I shall pronounce it a success and deem it a necessary part of my routine travel kit.

JULY: Bug Time

You can bet that I was scared. I had volunteered to test Lorena’s secret formula of adding Pennyroyal Herb Extract on top of DEET to thwart San Blas’ notorious no-see-ums (jejenes). It was 6:58 p.m., and the date was the last day of July. The outside air temperature was in the mid-nineties and the humidity was almost visible. I drove through town with the resignation of a condemned man.

It didn’t help matters any when I observed the marine guards outside the navy base on Avenida Batallón don their mosquito screen helmets as I drove by. The hour of warfare had arrived and I had an appointment on ‘the front line’, right out on the beach.

If I had to go, I was determined to put up a valiant fight: I slathered on the repellent and added six drops of Pennyroyal to each arm, each leg and to my face. (I know I told Carl that I would only use three, but I chickened out.) I opened my door and was greeted by a sauna-like blast of sticky, wet heat. With a sigh, I trudged towards the beach, past the empty palapas that sometimes house fondas (small restaurants). I stared out into the ocean. The waves were small; even they seemed weighted down under the oppressive humidity.

The Sun was a quarter inch from the horizon and was surrounded by an entourage of rust colored clouds. I turned south and started walking. I could feel tiny impacts of things hitting my skin, especially on my cheeks. Rivulets of perspiration ran down my body and my shirt clung to my back like a coat of fresh white enamel. “No tourists and no natives,” I grumbled. “Sure! They were home; safely indoors, while outside, on the beach, an unheard giant gong was announcing, “Dinner!” to half a trillion flesh crazed insects.

The Sun finally gave up and fell into the sea. I turned around and looked back. The palapas were a long way away. Something buzzed into my left ear, and I quickly smeared some excess lotion off an arm and into both ear canals. A few seconds later another critter flew into my left eye, and with a wince, I closed my eyes and rubbed it out. They got thicker. I could feel dozens and dozens of tiny impacts now. I inhaled some!

This was too much! I covered my nose and mouth as best I could and started back for the car, at a trot. The lurid stories about San Blas are certainly no exaggeration. I gave thanks that I had had the common sense to also drench the top of my (balding) head before I embarked upon this mad journey. Could those little airborne crocodiles munch their way through a cotton shirt? I had no way of telling. My primary thoughts were focused on GET BACK TO THE SAFETY OF MY CAR!

With a gasp of relief I opened the car door and made a wicked grin. My Momma didn’t raise no fool. I grabbed a can of Shelltox and fumigated the inside of the car. I waited half a minute, hyperventilated and then jumped into the front seat. I started the engine and zoomed down the street, past the enscreened marine guard. With a “whoosh!”, and at the point of turning blue, I ventilated the car by opening up all of the windows and the sun roof.

Later, I was sitting underneath the exhaust vent of a refrigerated air conditioner, taking stock of my condition. I had one juicy bite, right at my belt line, but I knew that I hadn’t bothered to coat this area with “The Mix”. So, even though I was annoyed at this welt, I was untouched otherwise.

Lorena, with a formal bow, I officially anoint your remedy with an “El Codo” endorsement!

¡Oye, señor! Déme un balazo de Tequila Herradura. Make that an Herradura Añejo! (Hey senor! Give me a glass of Herradura Tequila. Make that an aged Herradura!)


David “El Codo” Eidell

David trys another experiment with
Crocodile: Herbal Bug Discouragant

he People's Guide to Mexico
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