Nioxin Scalp + Hair Thickening Conditioner - System 4

All hair and skin types.

Almost always the first ingredient listed in water-based products.

Those looking for conditioning, slip, or richer textures in their haircare products.

Despite the name, fatty alcohols like cetyl alcohol are non‑drying and are commonly used to add emollience and stability to formulations.

Those looking for improved slip, manageability and reduced static, especially in dry or textured hair.

It is often paired with fatty acids to enhance conditioning performance and provide a softer feel. It also helps detangle without weighing hair down.

People looking for conditioners or treatments that provide slip, softness and richer textures.

Although called an alcohol, it is a waxy, non‑drying fatty alcohol commonly used to enhance conditioning performance and product stability.

Those looking for improved detangling, softness, and reduced frizz.

It is a common quaternary ammonium compound used in conditioners to enhance hair manageability. It works by coating the hair fibre, helping it feel smoother and easier to comb.

All products that need protecting from spoilage.

A very common, well-studied preservative used at low levels.

Those interested in understanding preservative systems or identifying potential fragrance allergens.

Benzyl Alcohol is commonly used in professional haircare to support product stability and texture. It can also naturally occur in some essential oils.

People looking for smoother, more manageable hair or richer, creamier product textures.

Despite the name, fatty alcohols are moisturising and conditioning rather than drying. They also help stabilise and thicken many haircare formulas.

Those who prefer products with a smoother, more cushioning texture or want improved slip in shampoos and conditioners.

It can also provide light conditioning benefits by helping hair feel softer and easier to detangle. It is commonly used in both rinse-off and leave-in products.

Those who like richer conditioners or masks that feel smooth and spread easily.

It also offers light conditioning and can help soften the feel of hair. It is widely used in both skincare and haircare for its reliable stabilising properties.

Those seeking added slip, manageability or a richer, more emollient feel in conditioners and treatments.

Fatty alcohols like oleyl alcohol are different from simple drying alcohols and are commonly used to enhance texture and conditioning performance in haircare formulas.

Those who enjoy invigorating, minty formulas or products designed to refresh the scalp.

Peppermint oil is commonly used in small amounts for its sensory benefits and perceived scalp‑refreshing qualities. As with many essential oils, sensitivity varies between individuals.

Those who enjoy refreshing, minty sensations or products designed to invigorate the scalp.

It is commonly used in haircare for its characteristic aroma and cooling effect. Essential oils are typically included at low levels to support sensory benefits.

Anyone using products that benefit from a long, reliable shelf life.

Propylparaben is a widely used preservative that helps maintain product quality and freshness. It is used at very low levels and is well studied for its role in keeping formulations stable.

Those using creams or conditioners that rely on smooth, even textures.

It is widely used in haircare to ensure consistent texture and to help disperse ingredients evenly. It also offers mild surfactant properties that support product spreadability.

Most hair types as part of a moisturising formula.

A widely used humectant and carrier ingredient.

Anyone who wants products to stay fresh and stable over time.

Parabens like methylparaben are widely used because they are effective in very small amounts and have a long history of use in cosmetics. They help maintain product quality, especially in water-based formulas.

All products, especially in hard-water areas.

Used in tiny amounts to keep formulas performing reliably.

Those who prefer products with a smooth, uniform texture or need easier application and distribution.

It is derived from cellulose and is widely used because it provides viscosity without weighing hair down. It also helps improve the feel and spreadability of many water-based products.

Most hair types as part of a balanced formula.

Usually present in small amounts to balance the formula.

People seeking improved manageability, reduced frizz or a silkier feel in their hair.

It is a cationic ingredient that deposits easily on the hair surface to enhance slip and detangling. Commonly used in conditioners, masks and leave-ins for a smoother finish.

A fragrance component that must be listed separately on labels because a minority of people can be sensitive to it. Its presence is normal, required disclosure and is not a quality signal.

Those interested in soothing or antioxidant-rich botanical ingredients.

It is commonly used in haircare for its calming and conditioning properties. Its gentle nature makes it suitable for a wide range of formulations.

Those looking for support with hair strength, manageability or damage care.

This ingredient combines a cystine derivative with a silane structure to help improve hair feel and resilience. It is commonly used in modern strengthening and smoothing formulas.

Those looking for added conditioning support or antioxidant benefits in their haircare.

It is commonly used because it is more stable than pure vitamin E while still offering similar benefits. It appears in many leave-in and rinse-off formulations.

Those seeking added softness, moisture support or smoother-feeling hair.

It is a phospholipid commonly derived from soy or sunflower and is valued for its ability to enhance spreadability and moisture retention. It can also help stabilise certain formulations.

Those looking for formulas that help maintain a healthy-feeling scalp or the appearance of stronger hair.

In topical products it is used in small amounts to complement other strengthening or scalp-care ingredients. Its effects are supportive rather than dramatic on its own.

Most hair types, especially dry or dull hair.

A versatile, well-tolerated conditioning ingredient.

Those looking to support scalp comfort, strengthen hair, or maintain a healthy-looking scalp barrier.

It is commonly used in both skincare and haircare for its soothing and barrier-supporting properties. It pairs well with many other ingredients and is generally well tolerated.

People who prefer plant-derived ingredients, those seeking natural fragrances or antioxidant-rich extracts, and users interested in scalp-supporting botanicals.

Composition and activity vary with plant source and extraction method, so effects depend on concentration and formulation. As with many botanicals, some individuals may experience sensitivity or allergic reactions.

Fennel fruit extracts contain components such as anethole, fenchone, flavonoids and other phenolic compounds; small amounts of volatile oils can contribute to scent. In cosmetics they are commonly used for fragrance, antioxidant activity and as a supportive scalp/conditioning ingredient rather than as a primary treatment. Formulators select an extract type (aqueous, hydroalcoholic or essential oil fraction) based on the desired functional and sensory properties.

Anyone interested in products formulated for consistent performance or stability.

It is commonly used as a buffering agent to help keep a formula working as intended over time.

Those looking for plant-derived ingredients that can help maintain hydration in hair and scalp.

Sugar maple extract is often included with other botanical ingredients to boost conditioning formulas. It is typically used at low levels alongside humectants and emollients.

Those looking for gentle, plant-derived ingredients that support scalp comfort and overall hair conditioning.

Botanical extracts like this one are commonly added to enhance the sensory and supportive qualities of haircare formulas. Their benefits can vary depending on concentration and the overall product type.

Those looking for botanical ingredients that can help invigorate the scalp or brighten the hair’s appearance.

Lemon peel extract is often included for its refreshing scent and natural antioxidant content. Its benefits can vary depending on the formulation and concentration.

Those looking for gentle botanical ingredients that support moisture retention.

Sugar cane extract is commonly used in haircare for its natural humectant properties and is compatible with most formulations. It may also support overall softness and shine.

Those looking for gentle, nutrient-rich plant-derived extracts in their haircare.

It contains naturally occurring amino acids and polysaccharides that can support hydration and scalp comfort. It is widely used in both hair and skin formulations.

Those interested in balanced formulations that stay consistent over time.

It is commonly used as a buffering ingredient to keep haircare formulas stable and effective. It does not impact hair feel or styling performance.

Those who enjoy botanically inspired formulas or lightweight, refreshing additions to cleansing and conditioning products.

Orange fruit extract is commonly included for its natural sugars, mild acids and antioxidant content. It is typically used in low levels to complement the broader formula.

People seeking lightweight hydration or improved hold in styling products.

It is a carbohydrate derived from starch and is commonly used to support texture and moisture balance in formulations.

Those who prefer products with a specific colour or enjoy visually distinctive formulas.

CI 42090 is widely used in personal care for consistent, stable colour effects. It does not affect how the product performs on the hair.

Anyone who uses water-based products that benefit from reliable preservation.

It is commonly used alongside other preservation systems to maintain product freshness and extend shelf life. It is generally well tolerated in rinse-off and leave-in products.

All products that need a preservative system.

Often paired with other preservatives for broad protection.

Those who want products with reliable preservation, including professionals who need consistent shelf stability.

Ethylparaben is part of the paraben family, which has been widely used for many years due to its effectiveness in small amounts. It is often combined with other preservatives to create a broad‑spectrum system.

Those who want products with a longer shelf life and consistent performance.

Parabens like butylparaben are widely used and well-studied preservatives that help keep products stable. They are typically present in very small amounts to maintain freshness and quality.