Schmidt Pain Index (Which Sting Hurts the Worst?)

Getting stung by insects hurts, and some hurt (a LOT) more than others. Of course, this necessitates a 'sting pain' index by which to compare the aftereffects of meeting the business end of a stinger. Why, just last weekend when i was on an ill-fated canoe trip (I dumped out twice, in freezing water) and was stung by a particularly unruly bee, I was remarking on how useful it would be to place my excruciation in the context of other nasty bugly-bites.

Lucky for all of us, an entomologist named Justin O. Schmidt decided to take one for the team and let a lot of bees, ants, and wasps sting him. Then, he would rate the level of ouchiness in an admirably systematic method. He published his "Schmidt Pain Index" in 1984 (refined in later papers, eg 1990), which ranked the sting-pain on a scale from 0 (completely benign) to 4 (mostly dead). The descriptions of the stings he presents are borderline precious, hearkening back to wine-tastings or sampling a pungent perfume:

1.0 Sweat bee: Light, ephemeral, almost fruity. A tiny spark has singed a single hair on your arm.
1.2 Fire ant: Sharp, sudden, mildly alarming. Like walking across a shag carpet & reaching for the light switch.
1.8 Bullhorn acacia ant: A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek.
2.0 Bald-faced hornet: Rich, hearty, slightly crunchy. Similar to getting your hand mashed in a revolving door.
2.0 Yellowjacket: Hot and smoky, almost irreverent. Imagine WC Fields extinguishing a cigar on your tongue.
2.x Honey bee and European hornet.
3.0 Red harvester ant: Bold and unrelenting. Somebody is using a drill to excavate your ingrown toenail.
3.0 Paper wasp: Caustic & burning. Distinctly bitter aftertaste. Like spilling a beaker of Hydrochloric acid on a paper cut.
4.0 Pepsis wasp: Blinding, fierce, shockingly electric. A running hair drier has been dropped into your bubble bath (if you get stung by one you might as well lie down and scream).
4.0+ Bullet ant: Pure, intense, brilliant pain. Like walking over flaming charcoal with a 3-inch nail in your heel.


One of the worst stings was from Pogonomyrmex badius (an ant, above) which he "likened to pain that might be caused by someone turning a screw into the flesh' or "ripping muscles and tendons." Wow. That is serious dedication to your work. Anything that has 'badius' in its name, well i'm steering clear of.

But perhaps the worst sting of all goes to the Pepsis wasp (or Tarantula Hawk, yeah it kills tarantulas. Pictured below.). Rather than light or fruity or shag-carpety, he described the pain as "...immediate, excruciating pain that simply shuts down one's ability to do anything, except, perhaps, scream. Mental discipline simply does not work in these situations."


Schmidt ended up rating 78 species of stinging insects. Check out some of his papers here:

Schmidt, J. O. 1986. Chemistry, pharmacology, and chemical ecology of ant venoms, pp.425-508. In T. Piek [Ed.], Venoms of the Hymenoptera.. Academic Press, London

Schmidt, J. O. 1990. Hymenoptera venoms: striving toward the ultimate defense against vertebrates, pp. 387-419. In D. L. Evans and J. O. Schmidt [Eds.], Insect defenses: adaptive mechanisms and strategies of prey and predators. State University of New York Press, Albany.

Schmidt, J. O., M. S. Blum, and W. L. Overal. 1984. Hemolytic activities of stinging insect venoms. Arch. Insect Biochem. Physiol. 1:155-160.

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So i'm guessing a bullet ant sting is pretty damn painful right, but is it deadly?

I was stung by an extremely small scorpion while carelessly walking out to the garage in my las Vegas home for a sweet treat. I stepped on the little bugger but only felt a tickling sensation until about 5 seconds had passed when I thought to myself "did someone just shove a lit match into an open wound in the side of my foot?!"
this was a few years ago and i was only 12 at the time so I immediately ran inside to my parent's room jumped on their bed and started to scream between my sobs at my mother that a scorpion had stung me. my dad in the other room heard me yelling and rushed into the garage to find it so we could possibly bring it to a doctor or venom expert, it turned out to be a young and very small bark scorpion. since i am such the bookworm and frequent the discovery channel I knew that the smaller it was the more potent the venom would be so I started to panic and sob even more in pain. my parents thought that the ER probably wouldn't be able to help me except to give me pain killers and poison control had no advice for me. that was probably the worst night of my life because i got stung around 6 o clock and was awake still crying until about 5 in the morning when my foot all the way up almost to my thigh went numb and i fell asleep.
the next few days afterwards especially the morning following i had difficulties walking on that leg and it was numb for nearly a week after.

my advice for anyone who gets stung is breath deeply, don't panic, put ice on it for extended periods of time, elevate the spot where stung if possible, and go to a hospital to get some real painkillers instead of the wimpy household advil.

I have recently moved to Virginia from Las Vegas and would like advice on how to keep the wasps away from me as I am a cnidophobic, or i have a severe fear of stings, because of my earlier experience.

By hockeyboy 2094 (not verified) on 18 Apr 2009 #permalink

I was whacked by a paper wasp just last week on the palm and wrist after i cupped it reached over a wooden gate. It was instant agony akin to holding a ball made of sea urchin broken glass and sharks teeth drenched in boiling sugar. My hand then became so swollen the bruising just below the knuckles is still visable 6days later ( if it wasnt for the agony i'd put one on my nob, actually i'm passing out just thinking about that). The sensations continued without relenting for 48 hours inducing extreme perspiration, dizyness and insomnia. My arm still feels tenderised ala post electric shock.

So where do Bark Scorpions range on the pain index?

If Schmidt took 78 different stings it would have been very likely over a period of more than 78 days due to logistic issues of shipping live species to destination, which is easier than going to a few dozen places. I believe antibodies accumulate in the blood as different stings are taken, which would lessen the impact of successive stings. That would impose an aspect of invalidation on the study. I have taken red harvester ant sting, and red wasp sting. The ant had me in tears, but the wasp made me yell for 7 hours. Sting site matters; did he take stings in comparable site? Cheek will hurt worse than thigh. I can't feature a bullet ant sting hurting as severely as an Australian bulldog ant envenomation. Having never sampled either, how do I so conclude? 30 bulldog ant stings cause adult human fatality, whereas over a 100 bullet ant stings, as per glove ritual, do NOT. Pain severity is not totally objective like which stack of quarters is higher than the others. Why ignore the puss caterpillar?

I was stung in the hand by a bullet ant on a river trip in remote Honduras a few years ago and Schimdt's description is apt. For about forty minutes I couldn't hold still, alternately pacing rapidly, dunking my hand in the river, shaking, squeezing, pinching - nothing helped. It's an experience I'm glad I had now, although at the time it was AWFUL.

IMPORTANT: the paper wasp, mentioned as 3.0 is NOT the common polistes wasp (!!!

Many people are misleaded because of the simple english name: paper wasp.
Most of the polistes wasps are neighter agressive nor have they a painful sting!

So that paper wasp flying around my office right now is a 3? That's good to know. I'll try not to look at it funny.

it's good to hear that the bullet ant is a 4+. The tucandeira (as its known in amazonia) can apparently give you a low fever from a single sting.

I got pegged by a paper wasp a few years ago (fortunately, it was happy with the one sting and didn't feel a need to repeat the performance). It felt like someone had jabbed a hot soldering iron into my shoulder. It was a deep and persistent burning sensation that went on long after the sting. I was advised to look out for signs of blood poisoning and tetanus; apparently wasps are potential carriers of some nasty microorganisms.

Mostly around here (NW AZ) I've been stung by the local large black ants. They're pretty aggressive -- they grab on with their mouthparts and sting the h*ll out of you until you pry them loose or pinch them away. Usually I've been hit in the knees because that's how high they manage to climb before becoming constricted by clothing and panicking. The stings feel a little like being poked repeatedly by a straight pin.

Getting my earlobes pierced hurt less than the ant stings, but was about the same as their pincers.

Somewhere between paper wasps and black ants is jumping cholla, partly because you usually get several spines in the leg, not just one, and because the spines are barbed and tend to hurt more going out than in. Removing them without tools (a la kitchen tongs) is a further guarantee of more spines in your fingers and thumbs.

I consider jumping cholla and mosquitoes to be two elegant proofs of the nonexistence of a benevolent god.

How about a list of the Australian animals that *aren't* dangerous? "Some of the sheep".

Someone apparently hasn't been stung by a fire ant that was serious. It is far worse than a yellowjacket and far more long-lasting.

Not being someone familiar with the chemical processes that cause the pain from a sting (other than the mechanical damage to tissue), I'm wondering what risk this research posed to Mr. Schmidt. Does anyone know if he suffered any long-term damage or was it just a matter of cussing for an hour or two afterwards?

I gotta say, though. He kinda makes Scoville seem like a wimp (although I think Scoville used a research group to reduce subjectivity).

Different stings definitely have different characters. I experienced two memorable encounters with stinging Hymenoptera in Panama last year. One was in a park, by an insect I never saw; I felt something tickle my head, reflexively brushed it out of my hair, and got grabbed by the finger and stung deeply enough to draw blood. Just as reflexively, I flung the critter into the brush, where it flapped away angrily -- I think it was either a wasp or a large queen of one of the many local stinging ants. It was definitely a swear-out-loud, stomp-up-and-down kind of sensation, but it was gone within fifteen minutes.

A week or two earlier, on Barro Colorado Island, I had offended a nest full of Parachartergus, a small paper wasp, and several of the residents came after me. Two stung me on the back of the hand, and a third on the tip of the nose. Those stings were nowhere near as painful as the one I got in the park -- but the annoying prickling sensation was still with me four or five hours later. Even though it didn't hurt all that much, I recall having to take some aspirin for the pain before I could fall asleep that night.

I'm loving hearing about all your sting stories! Luckily the worst thing I've even been stung by was your run-of-the-mill Apis mellifera or house wasp, but the concepts of stinging insects intrigue more than frighten me. All the comments here have gotten me thinking about what the biochemical actions of these venoms are...I mean, we're talking about fractions of microliters which are causing this much pain and cussin'

I think it bears investigating. Stay tuned tomorrow. :)

the concepts of stinging insects intrigue more than frighten me.

Possibly one of the most singularly unpleasant experiences I ever had was when I was standing outside in Wisconsin one day and a yellowjacket landed on the top of my earlobe.

It then proceeded to crawl into the space between my ear and my head, possibly probing for a sip of the cold sweat that had suddenly begun pouring off me when it landed.

It continued to crawl around toward the back of my ear, still tickling in an extremely disconcerting way inside the crease, before deciding to fly away, leaving me unharmed but with a pulse that would have rivaled Kevin Beck's after a marathon.

I'm not particularly terrified of stinging insects any longer, but I have some respect for what they can do.

Someone apparently hasn't been stung by a fire ant that was serious. It is far worse than a yellowjacket and far more long-lasting.

In my experience I've found individual fire ant stings aren't that bad by themselves, but rather it's their ability to sting en masse that compounds the pain in typical attacks.

Um, yeah, i got stung by a bullet ant in Costa Rica. Paraponera clavata. Pain is right in the name. After the searing pain subsided i was left with a burning pain that crept up my arm towards my heart. I'm glad it never made it that far. A few hours later the burning pain was gone, and I was left with general numbness. I would strongly recommend looking where you put your hands if you're in bullet ant territory.

By (not verified) on 16 May 2007 #permalink

One of the worst bites froman insect was from a DEER FLY. Very painful and leaves a nasty open sore.

My grandfather was an entomologist and I remember as a kid having science projects where he would help out. We'd go out and collect insects and he'd just grab wasps and bees and other stinging critters with his bare hands getting stung and it wouldn't even phase him. I don't think there were any bullet ants however.

When I was 10 or so, I once stumbled upon a wasps' nest--the common sort in the Midwest--and got stung a dozen or more times. It was painful, but finally not all that bad. I remember more the fear than the pain. The pain, as I remember, subsided quickly.

Other poisonous stings that are interesting are from fish. I once got stung by a stingray and that was truly painful. For twenty minutes or so, I could basically not speak. The only thing I could think of was the pain. Fortunately it takes a short while to sink in so I was able to tell a lifeguard what happened before it hit with a vengeance.

The pain altered between dull-throbbing and acute peaks which seemed to be in other parts of my body than the foot and leg that were struck. Then for another half-hour or so I remember the throbbing subsiding but far to slowing for my liking.

I would probably put it at about 3.5 on the above scale. In regards to the pepsis, it seems similar but without the need to scream. I also remember trying to control my breathing by taking deep regular breaths so as not to panic.

Worst was probably a little brown scorpion of some kind...that was significantly worse than a yellow jacket.

The guy should have let one bug sting him on the back of each hand, then see which hand grabbed the other in pain. That way he could compare them semi-directly, sort of like the rock hardness scratch tests. That'd involve a lot of extra stings, but it's for a good cause.

Like Cameron, I got nailed by a scorpion and still consider it worse (but it's close) to paper wasp. I developed a weird sensitivity to yellow jacket venom(area would swell a lot and bruise) so I avoid them at all costs.

Here the cow killers ant/velvet ant (actually a flightless wasp) Dasymutilla occidentalis is common but haven't met anyone who has been stung. Considering their vivid warning coloring and relative somewhat non-agressive behavior, maybe those stings are not that common.

Great post Shelley. I've had a few harrowing experiences. When I was 4 I stepped into a yellowjacket nest in a pile of old tree stumps I was climbing on. I sufferred several extremely painful stings, and had serious swelling that didn't subside for hours. Certainly not an experience I recommend. At 8, I got caught in a riled up fire ant mound right after a rainstorm. I sat to watch some older kids play football when I suddenly found myself covered in the damned things. I ran home, my folks saw me and stripped me in the doorway and tossed me in a bathtub and scraped them all off me. I was covered in welts and didn't fully recover for a while. I've also been stung by the inch or so golden-brown scorpions they have here in central Texas. For my money, the yellow jackets were the worst, followed by the ants and then the scorpion, but its hard to compare when the numbers are so disparete. And while they aren't poisonous, I wouldn't get too careless with either praying mantises, or stag beetles. Both can draw blood from a small finger.

Mr. Schmidt, we all owe you one. Talk about dedication to the job. But let's not tempt him to go doing this with ocean critters, or we'll have one less entomologist.

Looking at that beautiful pepsis wasp reminds me of one of my first wildlife rules of thumb: if it's pretty, it's dangerous.

Hrm, I didn't realize what I was signing myself up for promising to deconstruct these venoms. The papers are surprisingly few and far between, and hard to get my hands on. I'm gonna blog this, but may take a bit of time to get enough good info to do so.

Avenger, did you really get bitten by a mantis? Yikes! I heard they can spit too, but I wonder if thats just urban legend. I agree the pepsis is very beautiful (yeah, flashy and deadly.)

While I'm certainly no expert, I'd always understood that ant venom, at least, contained acetic acid. Possibly wasp venom as well.

Cameron, perhaps you were hit by a bark scorpion. They're fairly small, have a reasonably robust body shape, and surprisingly toxic venom.

While the US southwest has several varietes of scorpion, the bark scorpion is the only one considered genuinely (as opposed to relatively) dangerous.

Avenger, did you really get bitten by a mantis? Yikes! I heard they can spit too, but I wonder if thats just urban legend.

Yes, we learned to catch the mantises and how to hold them upright where they could not reach us, and we would catch grasshoppers and antagonize the mantises with them and then let the mantis take out his frustrations in rather viscious fashion on them. I got overly exuberant while bashing the mantis with the grasshopper, and the mantis caught my finger and well, my finger wasn't in full working condition again for a few days. I don't believe mantises can spit, but grasshoppers do.

Speaking of beautiful, flashy and, I won't go there :) Ahem, has anyone been unfortunately enough to get nabbed by the giant centipedes that frequent central Texas? In this case they are bigger and better here, and they are very pretty (red heads, black 7 inch bodies, yellow legs, and green rear pinchers), and they destroyed every other multilegged critter I tossed in with them, including each other. If anyone did get bitten by one, I'm sure its something they won't soon forget.

Growing up in Houston, there were quite a few stinging insects around, but the one that we kids learned (the hard way) to be most wary of was a small, white, fuzzy caterpillar that we called an "asp." I gather that it is also known as the "puss moss caterpillar." It was typically found on trees (I forget which kind it favored, although I once knew very well; birch maybe). The slightest contact produced an instant, blinding pain that felt very much like a cigarette burn--and left a blister much like that, too.

I've got nothing on you guys but stupidity. I was fast asleep and rolled over onto a bee (just a regular honey bee I think) and it stung me in the eye. Jerking awake and instictively grabbing my eye and tossing away the small critter I found there, I bolted upright and was greated with slighty blurry vision and a warm throbbing pain.

I had been a while since I had been stung by a bee, so I decided I should look up on the internet to find out what you should do when you get one. It took about 5 minutes to get my computer up and running and my vision got steadily blurrier in that eye. Finally finding the info, I discover that the first thing you should do is remove the stinger, as it has a venom sac that continues to pump venom for up to 5 minutes. Well of course I've been sitting on the computer for 5 minutes with venom pumping into my eye. By the time I took it out I'm sure it was quite done pumping venom.

About an hour later I was fine though, so really it was just a painful lesson learned.

Heh, you know, Wednesday we had a presentation at the hospital about local wildlife -- snakes, scorpions, etc. -- just a week after this post.

That night I found a spider climbing up the wall. I figured it was another small wolf spider -- I get them frequently -- and trapped it, but it didn't behave like a wolf. It moved a little too slowly and its body's proportions were all wrong.

So I examined it, got pretty sure of what it was, and took it to work the next day to ask our venomous creeatures presenter (who is also an anesthesiologist here) for confirmation.

He concurred; it was a local variant of a brown recluse, which is -- along with the black widow -- one of the two most toxic spiders in the US.

Story and pics in my blog for those who are interested.

What, no assassin bug stories??
I have an indoor wood box for my wood stove. Last spring while watching TV late at night I heard a buzzing between my head and pillow, pulled the pillow away and saw what looked like a black wasp running around in circles. I swatted it across the room and was stung in the finger. After waking everyone in the house by my screaming and not knowing what just hit me I watched my finger swell and turn white and continue to BURN for about 20 minutes. It then subsided to a level of pain of, say a wasp. I mentioned it to friends and was suggested it might be an assassin bug. I didn't have the critter since it was flung across the room so I couldn't verify that. But I did an internet search and read about them and checked out some pictures. About a week later same sort of scenario, this time it flew across the room and crashed into my lamp. I caught the critter in a jar and sure enough thats what it was. I felt confident I had taken care of the problem until it happened again, and I caught that one. Now i'm really scared to be up at night since it seems they are poor fliers and are drawn to lights at night. They also let out a smell sort of like vinigar when ticked off. Yep, thats how I found the next one, I smelled it and was stung in the foot while looking for it. I live in California but understand in Central America they have a really bad variety that carries a disease called Chagas. As I understand Charles Darwin is suspected to have died from that. It is sort of like "mad cow" disease, eats the brain after some years.
Anyway my point is, I have been stung by all sorts of critters but the assassin bug is the only one that really scares me, the pain is off the scale. Also caused tissue damage in my finger that took months to heal.
"MOST EVIL BUG" in my book
Look on the internet and read about these things, it'll keep you up at night......................

argh! i just posted your post, but as usual, an inferior version. conturnix pointed it out to us...

i actually search on the scienceblogs homepage first for justin schmidt sting and got no results... grrrrrrr.....

No worries Andrew, I think that search is broken anyway. The Schmidt index is great, glad to see you thought so too! :)

While I'm certainly no expert, I'd always understood that ant venom, at least, contained acetic acid. Possibly wasp venom as well.

Actually, it's typically formic acid plus a few other neat chemicals (what they are usually depends on whether the sting evolved as an offensive one or defensive). One anomaly is the aforementioned Pogonomyrmex genus... they're not carnivorous but the venom, besides being quite uncomfortable, is also more powerful than most other insects. In fact, the P. maricopa species has the lowest LD50 value venom out of all known insect stings... and they hurt like a son of a bitch. Interesting sting mechanism as well - stinger isn't robust enough to puncture your skin on its own so they chew a hole in you and then proceed to spray the wound. Really sucks when you get about five of them on you at once... feels like white hot needles being inserted into pores on your skin, and it burns for anywhere from half an hour to several hours depending on a few factors.


Yes, I too immediately thought of those beloved "asps," but couldn't think of their real name. I seem to recall them on maple and plum trees. I'd put them somewhere in the range of 2.5-3.5, but then it's been years since I was hit by one. For those of you not familiar, this is the kind of pain that blocks out everything in the whole world except the pure essence of ouch. And just for maximum thrills, this usually happens to kids climbing trees.

They don't have the decency to warn you. No buzzing, crawling, or other clues that the whole world is about to come crashing down. They ambush. And they're not even pretty: just a white hairy lump less than half an inch long.

Having been hit by hornets (bailing hay in Maryland (felt like I got hit with a hammer)), yellowjackets (at Grand Canyon in Arizona (betten multiple times (like being burned))), sweat bees (in Maryland (almost like really good hot sauce)), Honeybees (in New Hampshire at college (mild)), Fire ants (while providing support for the National Guard troops at Katrina (not painful but itchy as hell)), a saddleback caterpillar (in Maryland while trying to burn some smut infected corn (like spilling acid under a fingernail), some kind of red ant (at Death Valley (too young to remember)), brown tarantulas (Death Valley and Grand Canyon (like a sweat bee)), I can say categorically that the bald-faced hornets near the town of Halfway, Oregon (I was there for a forest fire) are, without doubt, the most painful bite in the lower 48 United States. Although a Rottweiller can hurt pretty bad, too.

By (((Billy))) (not verified) on 30 Jan 2008 #permalink