K18 makes three shampoos, and they are not interchangeable. One is for every wash, one is a weekly reset, and one is a toning shampoo for blondes. Most people end up owning two of them. Here is how to choose, with ProHair prices.
Damage Shield Protective Shampoo: the everyday wash
Damage Shield cleans with plant-derived surfactants in a formula that mimics hair’s natural pH, which limits the cuticle swelling during washing that drives frizz, colour loss and dullness. It is certified scalp-microbiome-friendly, colour-safe, and the K18PEPTIDE™ helps reduce protein loss. Pair it with the Damage Shield Protective Conditioner: ceramide NP, jojoba and sweet almond oils, no film-forming silicones, and, K18 reports, protection from UV and styling damage for up to 3 days. Sizes: 53 ml $14.29, 250 ml $40.00, 473 ml $60.36, 930 ml $102.50. Save by buying the Damage Shield Duo in the same size. Shop Damage Shield Shampoo.
Peptide Prep Detox: the weekly reset
A clarifying shampoo with activated charcoal and salicylic acid. K18 reports it removes 99% of product buildup, 95% of sebum and 76% of copper in one wash. Use it once a week in place of your regular shampoo, or whenever hair feels coated or dull, and always before a mask day if you can. It is colour-safe. Sizes: 53 ml $14.29, 250 ml $40.00, 473 ml $60.36, 946 ml $102.50. Shop Peptide Prep Detox.
TripleBright: brass control for blondes
A purple foam shampoo that tackles brass at its cause. Hard-water metals and minerals oxidise inside lightened hair and turn it yellow; TripleBright’s ionic detox removes them, violet pigment neutralises the yellow already there, and a biopolymer helps stop metals reattaching. K18 says one wash removes up to 3 months of hard-water brass. Leave it on 1 to 3 minutes and use it 1 to 2 times a week. Sizes: 125 ml $40.00, 443 ml $102.50. Shop TripleBright.
The combinations that work
- Coloured or damaged, soft water: Damage Shield every wash, the mask once a week.
- Hard water, swimmer or heavy product user: Damage Shield most washes, Peptide Prep Detox once a week followed by the mask.
- Blonde: Damage Shield most washes, TripleBright 1 to 2 times a week, the mask after TripleBright.
Quick decision guide
- You want one shampoo for every wash → Damage Shield
- Your hair feels coated, dull or you live with hard water → Peptide Prep Detox
- Your blonde turns yellow → TripleBright
- You are about to use the mask → Peptide Prep Detox, then no conditioner
FAQ
Can I use Peptide Prep Detox every day?
It is designed for weekly use or as needed. For daily washing, Damage Shield is gentler.
Will TripleBright turn my hair purple?
K18 formulates it to tone without staining or overtoning. On very light or porous blonde, keep to 1 minute at first.
Do I need the conditioner?
On non-mask days, yes. On mask days, skip conditioner and go straight to the mask.
Compare every size on the K18 collection page and read how to use the mask.