Table 4.

Summary of skin irritation studies of cocamidopropyl betaine (CAPB)

Subjects	Dose	Results	Refs.
Albino Rabbit (n = 3)	50% diluted 1:1(v/v) CAPB,	Not a primary irritant	[55]
Albino Rabbit (n = 6)	30% active CAPB	Primary irritation index (PII) = 0.5 Mild primary irritant Very slight erythema	[56]
Albino Rabbit (n = 3)	7.5% active CAPB solution	No irritation	[57]
Albino Rabbit (n = 1)	10% active CAPB solution, pH 6.1	PII = 0.25 No irritation	[43]
Rabbit (n = 6)	10% active CAPB solution, pH 4.5	PII = 0.3 Very slight erythema	[58]
New Zealand White Rabbit (n = 6)	30% active CAPB	PII = 3.75 Eschar formation	[59]
Albino Rabbit (n = 3)	15% active CAPB solution	PII = 3.5 Not a primary irritant Well-defined erythema Slight edema	[60]
Human (n = 10)	- Two soap formulations of 1.9% active CAPB - Cumulative occulsive patches for 21 days	Total irritation scores: 588 and 581 Primary irritants	[9]
Human (n = 19)	- 0.06% CAPB) - A single occulsive patch	No irritation	[10]
Human (n = 12)	- 0.52% CAPB - Occulsive patches for 5 days	Erythema score: 0.48 (scale 0–4)	[10]