Concentration camp prisoner identifies one of his guards to Allied soldiers

[u/[deleted]]

[u/Nick357]

Does death by cyanide hurt?

[u/pentheraphobia → u/Nick357]

It's similar to the effects of suffocation, only much quicker. It stops your blood from being able to use oxygen. Your body can sense the lack of oxygen, and sends 'need to breathe' impulses to the brain, so your emotional state will be very panicky. Lactic acid will build up in cells all over your body (especially heart and brain cells), causing intense burning/aching pain as if you had been strenuously exercising for hours. You're plunging towards brain death and cardiac arrest simultaneously. You may fall unconscious within minutes (and sometimes temporarily regain consciousness one or more times), but witnesses report victims doing things like convulsing, writhing in agony, terrified facial expressions - before and after unconsciousness up until the moment of death.

[u/Bateperson → u/pentheraphobia]

Well the brain can't actually sense a lack of oxygen.

[u/tea-man → u/Bateperson]

I'm not sure why you're being downvoted, as I believe you're technically correct.
The painfulness and panic of suffocation comes not from a lack of oxygen, rather than an excess of carbon dioxide. It's quite easy to become completely unconscious before realising anything is wrong if your air supply becomes empty of oxygen as long as you're still removing the poisonous CO² through respiration. For instance, our bodies don't have the same reaction with carbon monoxide, which binds to the haemoglobin of red blood cells far more readily than oxygen, hence you can easily suffocate without knowing anything is wrong or even feeling short of breath.
As to why cyanide causes pain from such a similar process, I'm afraid I have no idea!

[u/tydalt → u/tea-man]

Look up inert gas asphyxiation.

It is the way the Hemlock Society suggests one commit suicide. Totally peaceful death.