Instant Death poisons

In movies you often see the enemy agent who is about to be questioned quickly take a hidden poison pill, gurgle and die within about 5 seconds. Are there any such poisons that really work that fast? And if so when did they first become available? The movie I saw most recently took place in the early twenties.

Cyanide kills very quickly, you might have trouble administering it in such a way as to be absorbed fast enough but enough hydrogen cyanide gas would certainly do the trick. My old toxicology lecturer always used to say that if you ever saw hydrogen cyanide toxicity case where the patient was still breathing that patient was going to live.

Potassium Cyanide is pretty quick.
Unsurprisingly, there is little definitive information available.

Thanks for the replies.

Since it appears that Potassium cyanide fits the bill and acts by restricting cellular respiration, I am curious how it would be absorbed so as to get to the vital organs so quickly. I assume it wouldn’t have time to be digested?

The Downfall movie showed the rapidity of the effect very quickly.

The circulatory system is very efficient at moving stuff quickly through the body, as you have surmised the digestive system is something of a sticking point.

For the stuff to work quickly you would want it to be absorbed directly through into the bloodstream either through the lungs, direct injection, or through the mucous membranes in the mouth (the old cyanide capsules were designed to be held under the tongue, not swallowed). There are also substances that can facilitate rapid absorbance of poisons through the skin, although it would still likely take more time than you indicated in the OP.

KCN reacts with stomach acid to form the gas HCN, which is rapidly absorbed.

Previous thread.

Would a lethal dose of Nicotine produce similar results, particularly the speed at which one would become unconscious?


And would it be a painful experience?

Need answer fast? :eek:

I’ve always heard it’s a very painful death, really horrible. This article bears that out. But at least it’s over quickly.

Wikipedia notes that the “L-pill” suicide pill, issued to U-2 pilots and containing a lethal dose of potassium cyanide, took between 10 and 15 seconds to kill.

[Moderator Note]

I merged this thread on cyanide poisoning with another on instant death poisons because of their similarity.

General Questions Moderator

A hidden cyanide pill killed Himmler pretty darn quickly.

It depends on the form of cyanide, the purity, dose, and the route of administration.

This information is useful:

Thank you gentlemen. Have been able to find a great deal of information on Cyanide (and many other poisons), much of it here on the Straight Dope. Have not been able to find much comprehensive data on Nicotine though I know through several sources that it is deadly, about the same amount of Nicotine as Cyanide will kill.

"The lethal dose of nicotine has been reported as between 40 and 60 milligrams (the total amount in about 2 cigarettes if all of the nicotine was absorbed) in adults"

What I don’t know is does it kill the same way as Cyanide and as quickly.

Am including one of several explanations of Cyanide from other member of this community.

"**Xenopus 04-04-2000,
The effects of cyanide on human tissues vary considerably depending upon the time frame or type of dose. If you ingest cyanide, the tissue effect is a combination of the ions interfering with oxygen transport OUTSIDE of the cells by poisoning hemoglobin, and also by affecting electron transport INSIDE the cell, specifically inside the mitochondria, by poisoning the cytochromes.

But gaseous inhalation is supposed to work much quicker because it blocks the oxygen transport system fairly rapidly. This is why gaseous cyanide is such a killer, compared to the solid form (which still isn’t a bouquet of roses)."

If anyone can find a similar explanation similar to this about Nicotine I will appreciate it.


There was once a website, which disappeared years ago, that had several suicide recipes, including one for distilling a lethal amount of nicotine from several dozen packs of regular cigarettes.

It didn’t work.

Just so you know.

Does anyone else see a potential for the transdermal nicotine patches now sold OTC in the US?

At least I know why they originally required prescription.

(I quit smoking by deliberate OD on nicotine - I do have some experience)

And - on the subject of instant-acting opioids:

Is the orally administered “morphine” seen being used by emergency medical personnel on horribly injured victims (life expectancy in minutes type injuries) a real thing?

I have been through several opioids, now on an ER formula, so no comparison, but what the hell is the morphine in that oral administration works in seconds?

Or is there such a drug, but it is not morphine, any more than the the stuff a Dentist uses is Novocaine?

The formula for extraction may not have worked but there is definitely enough nicotine in a dozen packs to kill an average adult, probably a few times over, according to the most liberal projections I’ve read.


I’m curious about this as well. When I was in high school, our chemistry teacher’s supply room had a big jar (maybe two or three litres) full of liquid nicotine. Even back then I had heard that it was a deadly poison, and that it could be absorbed through the skin, so I was wondering what purpose it would possibly have in a high school chemistry lab. Does anyone know?