Scalp Revival Charcoal + Tea Tree Scalp Treatment Serum

The base most products are built on. It carries the other ingredients and has no safety concern.

A plant extract used for mild astringent and soothing effects. Evidence for its benefits comes mostly from traditional use and small studies rather than large trials, and the tannins it contains can be mildly irritating for some people, particularly in older distilled formulas that retain trace alcohol.

A plant-derived water or extract used mainly as a soothing humectant filler. Evidence for dramatic skin benefits beyond mild hydration and soothing is limited, but it is well tolerated by most people.

A corn-derived solvent and humectant that has largely replaced propylene glycol in "clean" formulas; CIR reviewed the alkane diol group and found use concentrations up to about 40 percent in leave-on products like deodorant sticks with no meaningful irritation signal.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

A B vitamin (B7) included in cosmetics for skin and hair conditioning effects. It is graded with no known concerns in cosmetic assessments and is well tolerated across skin types.

A soothing humectant that helps skin and hair look conditioned. Very well tolerated.

Tea tree oil is used for its antimicrobial reputation in blemish-focused products, but it is a genuine, well-documented contact sensitizer, and its allergy potential rises sharply once the oil has oxidized from air exposure. Fresh, well-preserved, low-concentration formulations are much lower risk than old or improperly stored oil.

An essential oil rich in menthol and other terpenes. It adds a cooling, fresh note to products but is a known skin irritant and contact allergen, especially in leave-on products or for people with sensitive or inflamed skin. The oil oxidizes over time, increasing allergenicity.

A warming root extract with anti-inflammatory and antioxidant properties. Some individuals report mild warming or tingling sensations; those with sensitive skin should start with lower concentrations or patch test first.

A cooling agent derived from menthol that creates a tingling or cooling sensation on skin without the strong burn of menthol itself. It can irritate or sensitize reactive skin types, particularly in leave-on formulations or at higher concentrations, making it most suitable for rinse-off products or diluted formulas.

A naturally derived humectant made from fermented plant sugars that draws water into the skin. It is well tolerated in cosmetics and is used to support hydration and skin softness.

A humectant that holds water at the skin surface for a more hydrated look. No safety concern.

A more stable, esterified form of vitamin E used as an antioxidant and skin-conditioning ingredient. It is a different substance from the vitamin E acetate implicated in vaping-related lung injury, which involved inhaling the oil, not applying it topically to skin.

Used in tiny amounts to set a product to skin-friendly pH. No concern at those levels.

A linoleic-acid-rich plant oil used as an emollient and, in some small pediatric studies, associated with support of the skin barrier when applied to infant skin. It is well tolerated with a low reported rate of contact reactions.

A natural, plant-based emulsifier made from cetyl alcohol and glucose that mixes oil and water phases in cosmetics. It is well studied, nonirritating in published testing, and presents no known safety concerns for cosmetic use.

A water or bran extract of rice containing ferulic acid, small peptides and starches. It is a traditional East Asian skincare staple with some supporting antioxidant and mild-brightening data, but most of that evidence comes from cell or animal studies rather than large human trials, so the "brightening" claims on finished products go further than the direct evidence.

A widely used, gentle preservative also common in food. It is generally well tolerated, though it can occasionally cause mild, transient irritation in people with already-compromised or very reactive skin.

An aromatic plant extract rich in natural antioxidants, valued in skincare formulations for its protective properties. Published cosmetic assessments indicate it is generally well tolerated, though the botanical origin means some sensitive individuals may react.

A strong alkali used in tiny amounts to adjust the pH of cosmetics to safe, skin-friendly levels. At the pH found in finished products, sodium hydroxide is neutralized and well tolerated.

An antioxidant that helps protect a formula and condition skin. Well tolerated.

Xanthan gum is a microbial-fermentation-derived polysaccharide used to thicken and stabilize textures, similarly common in food. Cosmetic panel review of this and related microbial gums found them safe as used, with no meaningful irritation signal at typical concentrations.

A naturally occurring acid used to preserve and adjust pH in cosmetic formulas. It is generally recognized as safe at cosmetic use levels, with mild irritation possible on broken or very sensitive skin at higher concentrations.

A salt derived from citric acid that buffers pH and prevents metal oxidation in formulas. Widely used in food and cosmetics, it is well tolerated at cosmetic concentrations.

Dehydroacetic acid is a preservative regulated under the EU preservative annex with a set maximum concentration. Sensitization appears to be rare, though occasional contact dermatitis case reports exist, so people with reactive skin may want to patch test.

A common preservative and fragrance/solvent ingredient found naturally in many essential oils. It is well tolerated by most people at the levels used in cosmetics, but it is one of the 26 EU-designated fragrance allergens and can trigger reactions in people with an existing sensitivity.