KERASTASE Résistance Thermique Extentioniste Heat Protectant 150ml

KERASTASE Résistance Thermique Extentioniste 150ml is a strengthening heat-protectant blow-dry primer for long, weakened hair prone to breakage and split ends. Its lightweight gel-cream formula helps seal and resurface the hair fibre while protecting against heat styling up to 230°C, allowing lengths to remain stronger, smoother and healthier-looking as hair grows longer.

KERASTASE reports 93% less breakage after one application, while the formula helps seal split ends and improve detangling and manageability.

Heat protection up to 230°C – Protects long hair during blow-drying, straightening and heat styling.

93% less breakage – Designed to reduce the breakage that can prevent hair from maintaining longer lengths.

Seals split ends – Helps resurface damaged lengths and improve the appearance of weakened ends.

Strengthens long hair – Supports stronger, more resistant lengths.

Smooths & softens – Leaves hair smoother, softer and shinier while improving manageability.

150ml · Heat Protectant · Anti-Breakage · Long Hair · Split Ends · Leave-In

Best for: Long hair • Hair growing longer • Weakened lengths • Breakage-prone hair • Split ends • Heat-styled hair • Damaged lengths

What Is It?

KERASTASE Résistance Thermique Extentioniste 150ml is a leave-in thermo-protective blow-dry and heat-styling gel-cream developed specifically for people trying to maintain long, healthy-looking hair.

The challenge with growing hair longer isn't simply how quickly hair grows at the scalp.

Lengths can repeatedly:

Weaken → Split → Break → Require trimming → Lose length

Thermique Extentioniste targets this problem by protecting and reinforcing the existing lengths, particularly against heat-induced damage.

Its role is:

Protect from Heat → Reinforce → Reduce Breakage → Seal Ends → Smooth → Help Maintain Length

This distinction is important for our marketing: I would not sell this as a “hair growth cream.” It does not make hair follicles grow faster. Instead, it helps hair stay stronger and break less, which can help customers successfully maintain longer lengths.

Why You'll Love It

• Professional heat-protectant leave-in
• Specifically designed for long hair
• Ideal when growing hair longer
• Protects against heat up to 230°C
• 93% less breakage*
• Helps seal split ends
• Reinforces weakened lengths
• Resurfaces the hair fibre
• Improves detangling
• Improves manageability
• Leaves hair smoother
• Helps increase softness
• Enhances shine
• Lightweight gel-cream texture
• No rinsing required
• Contains Creatine
• Contains Taurine
• 150ml

*KERASTASE reports 93% reduced breakage after one application.

Who Is It For?

Ideal for:

Long hair
Hair being grown longer
Weakened hair
Brittle lengths
Hair prone to breakage
Split ends
Damaged lengths
Heat-styled hair
Hair regularly blow-dried
Hair regularly straightened or curled
Customers trying to maintain longer hair
Customers whose hair “won't grow” because the ends keep breaking

This last search intent is commercially useful. Customers often describe the problem as “my hair won't grow,” when their actual issue may be length retention due to breakage.

We can capture that intent in SEO without making an inaccurate hair-growth claim.

Pair Me With

KERASTASE Résistance Bain Extentioniste Strengthening Shampoo – Strengthening cleanser for weakened and brittle hair, formulated with ingredients including Taurine and Creatine.

KERASTASE Résistance Fondant Extentioniste Conditioner – Strengthening and detangling conditioner with Ceramides and Maleic Acid to support strength and elasticity.

KERASTASE Résistance Masque Extentioniste Hair Mask  – Intensive strengthening treatment for weakened lengths requiring deeper care.

Recommended Extentioniste Routine

Bain Extentioniste → Fondant Extentioniste → Thermique Extentioniste

For more damaged lengths:

Bain Extentioniste → Masque Extentioniste → Thermique Extentioniste

Thermique Extentioniste is the leave-in/prime step before blow-drying or heat styling.

Resistance Extentioniste Thermique Hair Heat Protection | Kérastase UK

Step 1
Apply a walnut-sized amount to towel-dried hair.

Step 2
Style using a hairdryer or heat styling appliance.

Step 3
Leave in

Aqua / Water / Eau, Isopropyl Myristate, Dimethicone, Triethanolamine, Amodimethicone, Phenoxyethanol, Carbomer, Polyquaternium-4, Potato Starch Modified, Hydroxypropyl Guar, Behentrimonium Chloride, Trideceth-6, Amyl Cinnamal, Hexyl Cinnamal, Isopropyl Alcohol, Benzyl Alcohol, Linalool, Hydroxycitronellal, Cetrimonium Chloride, Citronellol, Limonene, Benzyl Cinnamate, Creatine, 2-Oleamido-1,3-Octadecanediol, Taurine, Parfum / Fragrance.

This is the current official KERASTASE UK ingredient list. Your physical EU/Cyprus 150ml packaging should remain the final reference if the formulation changes.