Eugenol: Comedogenic Rating & Ingredient Analysis
Eugenol is the molecule that gives cloves their warm, spicy smell, and it is one of the 26 fragrance allergens that must be named on European cosmetic labels. It is found in clove, cinnamon, basil and nutmeg oils and is used in perfumes and warmly scented skincare. Among the declarable fragrance compounds, eugenol is considered one of the stronger sensitisers, so while most people tolerate it, it accounts for a meaningful share of fragrance-related allergic reactions and appears on standard patch-test panels.
Quick facts
- Comedogenic rating
- our estimate — not measured
- Irritation risk
- High
- Effective pH
- —
- Typical strength
- trace–0.3%
- Pregnancy
- Considered safe
- Suits skin types
- oilycombinationnormaldry
Where this number comes from
No one has published a comedogenic rating for this ingredient. Fulton's 1989 table tested about 250 raw materials and this was not among them, and we found no later study measuring it. The figure shown is our own reasoning from the ingredient's chemistry and how it is used — treat it as an estimate, not a measurement.
Fulton read his own scale as 0-1 not significant, 2-3 borderline, 4-5 positive. The assay is the rabbit ear at 10% dilution, which the paper itself calls extremely sensitive and not fully predictive of human skin. Ratings describe the raw ingredient; concentration and formulation change real-world behaviour.
Caution profile
The four published fields on this page, on one 0–5 scale. Further from the centre means more care is needed — never that the ingredient is worse.
Derived, not measured: pore-clogging is the published comedogenic rating; irritation maps low/moderate/high to 1/3/5; pregnancy maps safe/caution/avoid to 0/3/5; skin-type limits is how many of the seven skin types this entry does NOT list. Every input is printed in words in the quick-facts card above.
Show the numbers
| Metric | 0–5 | Published field |
|---|---|---|
| Pore-clogging | 0 | 0/5 |
| Irritation | 5 | High |
| Skin-type limits | 2.1 | 4/7 |
| Pregnancy | 0 | Considered safe |
Working pH and typical strength
Where this ingredient is formulated to sit, and at what concentration.
Both bars come from the fields above: the pH window and the typical strength range published for this ingredient. The tinted column is healthy skin's surface pH (about 4.7–5.75).
Show the numbers
| Metric | 0–5 |
|---|---|
| Typical strength | trace–0.3% |
What is it?
Eugenol is a phenylpropanoid — a spicy-smelling aromatic compound — used purely as a fragrance ingredient. Beyond cosmetics it has a long history in dentistry as a component of clove oil for its numbing and antiseptic properties, but in skincare it is present only for scent and carries no treatment benefit for acne, hydration or ageing. Its irritation and allergy potential is higher than many other fragrance allergens, which is why formulators keep it at low levels and reactive-skin users are often advised to avoid it altogether.
Benefits
Adds a warm, spicy scent
Eugenol contributes the clove-like note that defines many warm, oriental and spiced fragrances in cosmetics.
Naturally present in spice oils
It is the main aromatic component of clove and a significant part of cinnamon and basil oils, so spice-scented products contain it.
Long history in oral care
Its antiseptic and mild anaesthetic reputation comes from dental clove oil, though this is not its role in skincare.
Non-comedogenic
At fragrance concentrations it does not clog pores; the relevant concern is a comparatively high sensitisation risk, not comedones.
How to use
Eugenol is not applied deliberately; you choose whether to use scented products that contain it. Because it is one of the stronger fragrance sensitisers, people with any history of fragrance or spice-oil reactions should be especially cautious. If your skin is reactive, has eczema or rosacea, or you use sensitising actives such as retinol, salicylic-acid or glycolic-acid, fragrance-free products are the safer choice. Patch test any new eugenol-listing product on the forearm for several days, and keep spice-oil products sealed and cool to limit oxidation.
Side effects
Eugenol has a higher irritation and allergy profile than most other fragrance allergens. In sensitised people it can cause allergic contact dermatitis with itching, redness and sometimes a stinging or burning feeling on application. It can also act as a mild irritant on compromised skin even without true allergy. Leave-on products increase the exposure and therefore the risk.
Who should avoid it
People with a known eugenol, clove or cinnamon fragrance allergy should avoid it, as should anyone with eczema, rosacea or a damaged barrier. Because of its stronger sensitising profile, those with reactive skin or an active-heavy routine are best served by fragrance-free formulas.
Avoid combining with
Frequently asked questions
Is eugenol a strong allergen?
Relative to other fragrance allergens, yes — eugenol is considered one of the more potent sensitisers and appears on standard patch-test panels, though most people still tolerate it at cosmetic levels.
Why is clove oil sometimes flagged in skincare?
Clove oil is rich in eugenol, a declarable fragrance allergen with a higher irritation risk, so clove-containing products often carry the eugenol label and are worth patch testing.
Does eugenol help with acne?
No. Despite eugenol's antiseptic reputation in dentistry, in skincare it is present only as a fragrance and offers no proven acne benefit, while adding sensitisation risk.
Should sensitive skin avoid eugenol?
Yes, generally. Given its stronger sensitising profile, people with reactive, eczema-prone or rosacea-prone skin are advised to choose fragrance-free products that do not contain eugenol.
Sources & further reading
Medical disclaimer
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