The most important aftercare decision
The right shampoo makes your keratin treatment last 5 months. The wrong one — 5 weeks.
Most people who say keratin treatments "didn't work" are washing with sulphate shampoo. Here is exactly what to use instead.
Why your shampoo is the deciding factor.
A keratin treatment restructures the hair shaft from the inside. The treatment is not sitting on the surface — it is bonded into the cortex of the hair. To remove it, you need something that can penetrate the hair shaft and break those bonds.
Sulphates do exactly that. Sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES) — the main cleaning agents in most shampoos — are powerful enough to strip the keratin treatment out of the hair shaft with every wash. Not instantly, but gradually and consistently.
Over 6–8 weeks of daily washing with a sulphate shampoo, most of the treatment is gone. Over the same period with a sulphate-free shampoo, the treatment remains nearly intact.
This is not a minor difference. It is the single most important decision you make after a keratin treatment.
What to look for in a post-keratin shampoo.
Must be sulphate-free
Check the ingredients for sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES). If either is present, do not use it after a keratin treatment.
Sodium chloride-free preferred
Sodium chloride (table salt) is used in many shampoos as a thickener. It gradually breaks down keratin treatments, particularly on very smooth or fine hair.
Formulated for treated hair
Shampoos designed for keratin-treated or colour-treated hair use gentler cleansing agents and often contain proteins that complement the treatment.
pH-balanced
The hair shaft is slightly acidic (pH 4.5–5.5). A pH-balanced shampoo keeps the cuticle closed, preserving the treatment and adding shine.
Top recommendation
QIQI Smooth Service Shampoo.
Why it works
- Sulphate-free and sodium chloride-free
- Formulated to maintain QIQI Hair Controller results
- 19 precision-selected ingredients
- 95% of users reported nourished, smoother hair
- Available in 75ml (travel), 300ml, and 1000ml
- Free UK delivery on orders over £80
Ingredients to avoid after keratin treatment.
Sodium Lauryl Sulphate (SLS)
The most aggressive sulphate — strips keratin rapidly.
Sodium Laureth Sulphate (SLES)
Slightly milder than SLS but still strips keratin over time.
Ammonium Lauryl Sulphate
Another sulphate variant — avoid in all post-keratin products.
Sodium Chloride
Salt used as a thickener — gradually weakens treatment bonds.
Sodium Bicarbonate
Raises pH, opens the cuticle, accelerates fading.
High-alkaline formulas
Alkaline shampoos open the cuticle and allow the keratin to wash out.
Post-keratin shampoo FAQ
What type of shampoo should I use after a keratin treatment?
You need a shampoo that is sulphate-free AND sodium chloride-free (salt-free). Sulphates strip the keratin structure with every wash. Sodium chloride also degrades the treatment over time. Look for shampoos marketed specifically for keratin-treated or chemically processed hair.
What happens if I use regular shampoo after a keratin treatment?
Regular shampoo contains sulphates (usually sodium lauryl sulphate or sodium laureth sulphate). These are powerful cleaning agents that also strip keratin treatments out of the hair shaft. Using regular shampoo consistently after a keratin treatment can reduce the results from 4–5 months to 4–6 weeks.
When can I wash my hair after a keratin treatment?
Wait 72 hours (3 days) before your first wash after a keratin treatment. This allows the treatment to fully bond with the hair structure. When you do wash, use a sulphate-free shampoo and lukewarm water — not hot.
Is sulphate-free shampoo enough, or do I need sodium chloride-free too?
Both matter. Sulphates are the primary concern — switching from a sulphate shampoo to sulphate-free is the most important change you can make. Sodium chloride (salt) also gradually strips the treatment, particularly from hair extensions or very smooth results. If you want maximum longevity, choose a shampoo that is both sulphate-free and sodium chloride-free.
How long should I use a special shampoo after a keratin treatment?
For the entire duration of the treatment — 4–5 months. Once you switch back to a regular sulphate shampoo, the treatment will begin to fade more quickly. Many people continue using sulphate-free shampoo permanently because it is also gentler on the hair.
Can I use dry shampoo after a keratin treatment?
Yes. Dry shampoo does not contain sulphates and does not affect the keratin treatment. It is a good option for extending time between washes during the 72-hour waiting period and beyond.
What conditioner should I use after a keratin treatment?
A lightweight, sulphate-free conditioner is best. Avoid heavy conditioning masks immediately after — they can be too rich for freshly treated hair. QIQI Hydration Fixation Conditioner is formulated to work with the Smooth Service Shampoo for post-treatment hair.
Make your treatment last.
Sulphate-free shampoo is the single most important step after a keratin treatment. Free UK delivery over £80.
Shop Smooth Service Shampoo →