Florida Cosmetology Licensing ExamChemical ServicesMedium
A client with fine, damaged hair requests a chemical relaxing service. Which type of relaxer would be the safest and most appropriate choice to minimize further damage?
- AMetal hydroxide relaxer
- BThio relaxer (ammonium thioglycolate)
- CLye-based relaxer (sodium hydroxide)
- DGuanidine hydroxide relaxer (no-lye)
Show answer & explanationAnswer & explanation
Correct answer: D. Guanidine hydroxide relaxer (no-lye)
Guanidine hydroxide relaxers, also known as no-lye relaxers, are generally considered safer for fine, damaged, or sensitive scalps compared to lye-based relaxers because they have a lower pH and are less irritating, though they can still be drying.
Why the other options are wrong
- A. Metal hydroxide is a broad category; lye relaxers (sodium hydroxide) are a type of metal hydroxide and are too strong.
- B. Thio relaxers are typically used for permanent waving, and while they relax, guanidine is often preferred for sensitive hair.
- C. Lye-based relaxers are very strong and can be too harsh for fine, damaged hair.
Guanidine Hydroxide Relaxers (No-Lye)
A type of chemical relaxer that uses guanidine hydroxide as its active ingredient. It is generally considered milder and less irritating to the scalp than lye-based relaxers, making it suitable for sensitive or damaged hair, though it can be drying.
- Active ingredient: Guanidine hydroxide
- Marketed as 'no-lye' relaxers
- Lower pH than lye relaxers, less irritating
- Can be drying to the hair, requires conditioning
- Often a two-component system (cream + activator)
Memory trick: Lye is Strong, Thio for Perms, Guanidine is Gentle and Calm.