CheckVegan

Is Hydroxy Tetramethylpiperidine Oxide vegetarian?

Hydroxy Tetramethylpiperidine Oxide

Vegetarian Vegetarian
Vegan Vegan

Hydroxy Tetramethylpiperidine Oxide, commonly known as TEMPO or 4-Hydroxy-TEMPO, is a stable synthetic aminoxyl (nitroxide) radical compound used as a chemical reagent and, in cosmetics, as an antioxidant or stabilizing agent.

Also known as 1-Oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine, 1-Piperidinyloxy, 4-hydroxy-2,2,6,6-tetramethyl-, 1-λ1-Oxidanyl-2,2,6,6-tetramethylpiperidin-4-ol 2,2,6,6-tetramethylpiperidine-1,4-diol, 4-Hydroxy-2,2,6,6-tetramethyl-piperidinooxy, 4-Hydroxy-2,2,6,6-tetramethylpiperidine 1-Oxyl Free Radical, 4-Hydroxy-2,2,6,6-tetramethylpiperidinoxy, 4-Hydroxy-2,2,6,6-tetramethylpiperidinoxyl, 4-HYDROXY-2,2,6,6-TETRAMETHYLPIPERIDINOXYL-, 4-Hydroxy-TEMPO, HTMPO, Hydroxy Tempo
INCI name Hydroxy Tetramethylpiperidine Oxide
CAS number 2564-83-2
EC number 218-760-9
CosIng ID 96746
Last reviewed 4 July 2026

An ingredient is considered vegetarian if it avoids components derived from killing an animal.

Classifications are made to the best of our knowledge based on available scientific and regulatory sources. We cannot guarantee the accuracy of every entry, errors in the sources we draw from can always occur. This tool also cannot account for cross-contamination, which depends entirely on individual suppliers and producers. If you believe a classification is incorrect, you can report an issue.

Report an issue