SHEET /m/capsaicin · PubChem CID 1548943 · CAS 404-86-4 · REV 2026.07
Capsaicin from source
C18H27NO3 · 305.4 g/mol
Zostrix · CAPSAICINE · trans-Capsaicin · Qutenza
What is Capsaicin?
The molecule that makes chili peppers hot; it trips the same nerves that sense heat, so your mouth reads a burn that is not really there. Found in chili peppers and hot sauce. from source
Fig. 1 · 2D structure RDKit
CC(C)/C=C/CCCCC(=O)NCC1=CC(=C(C=C1)O)OC
Where you'll find it
Curated by MoleculeFinder from source
The dose makes the poison inferred
A reported rat oral LD50 for Capsaicin is 47.2 mg/kg, the dose lethal to half the animals tested. Scaled by body mass alone:
“The dose makes the poison” is a cross-species estimate shown as neutral science, not a threshold anyone should act on. Real toxicity depends on the person, not body mass alone.
How hot is it? computed
Scoville scale: peppers computed
Pepper heat ranges from about 5,000 units for the jalapeño up to about 1,700,000 for the Carolina Reaper, and capsaicin is the molecule behind all of it.
| Pepper | Scoville heat units |
|---|---|
| Jalapeño | about 5,000 |
| Serrano | about 15,000 |
| Cayenne | about 40,000 |
| Habanero | about 150,000 |
| Ghost pepper | about 1,000,000 |
| Carolina Reaper | about 1,700,000 |
Signature properties
Toxicity & hazards
Toxicity · LD50
47.2 mg/kg · highly toxic · LD50 rat oral from source
The dose lens above scales this to a body weight.
7 more reported values
- 47.2 mg/kgLD50 · oral · mouse
- 2,500 mg/kgLD50 · oral · mouse
- 0.4 mg/kgLD50 · iv · mouse
- 6.5 mg/kgLD50 · other · mouse
- 7.8 mg/kgLD50 · other · mouse
- 9 mg/kgLD50 · other · mouse
- 9.5 mg/kgLD50 · other · rat
Keep roaming
Where Capsaicin leads
Capsaicin doesn't actually burn tissue; it hijacks the same receptor that senses real heat, which is why your brain insists your mouth is on fire.