There is an ultrapotent analogue of capsaicin called " resiniferatoxin " that is naturally produced in two plants
It has an affinity for the transient vanilloid receptor 1 (TRPV1) that is roughly 500 times that of capsaicin ( capsacin is actually vanilloid - works on the same receptor as vanilla )
1 / 1,000,000 of one gram of resiniferatoxin is enough to cause intense pain
If you thought about the heat of capsaicin VS resiniferatoxin in terms of an analogy using size, say we'll use the Sun and the Earth ( Roughly 1 million earth's fit in the Sun )
The Sun is the resiniferitoxin and the Earth is the capsaicin
Remember that when you see people eating ghost peppers
...they haven't come close to hot
10 grams of resiniferitoxin is enough to kill you
Here's the breakdown
Scoville heat units Examples
16,000,000,000
Resiniferatoxin
5,300,000,000
Tinyatoxin
16,000,000
Capsaicin
15,000,000
Dihydrocapsaicin
9,200,000
Nonivamide
9,100,000
Nordihydrocapsaicin
8,600,000
Homocapsaicin,
Homodihydrocapsaicin
160,000
Shogaol
100,000
Piperine
60,000
Gingerol
16,000
Capsiate
The hottest Peppers by comparison:
855,000 – 2,200,000 Komodo Dragon Chili Pepper,Trinidad Moruga Scorpion, Naga Viper pepper, Infinity Chilli,Naga Morich, Bhut jolokia (ghost pepper), Trinidad Scorpion Butch T pepper, Bedfordshire Super Naga, Spanish Naga Chili,Carolina Reaper
Additional facts about resiniferitoxin include that it is being researched in connection with a novel pain treatment
It was also described as being used in an ancient medicine "
Euphorbia "