Citronellol: Comedogenic Rating & Ingredient Analysis
Citronellol is a rose- and geranium-scented fragrance molecule and another member of the European list of 26 allergens that must be named on cosmetic labels. It occurs naturally in rose, geranium and citronella oils and is added to a wide range of products to give a soft, floral character. As with the other declarable fragrance allergens, most people tolerate it without any reaction, but a minority become sensitised and develop allergic contact dermatitis, which is the reason for its mandatory declaration.
Quick facts
- Comedogenic rating
- our estimate — not measured
- Irritation risk
- Moderate
- Effective pH
- —
- Typical strength
- trace–0.5%
- 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 | 3 | Moderate |
| 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–0.5% |
What is it?
Citronellol is a terpene alcohol used as a fragrance ingredient and found in essential oils such as rose and geranium. It is also used in some insect-repellent contexts because of its relationship to citronella. In skincare it exists purely for scent — it does not hydrate, exfoliate or treat acne. Its allergy risk is moderate and, like related terpenes, can increase as the molecule oxidises with air exposure. For people who are not fragrance-sensitive it is a non-issue; for reactive skin it is one more scent component worth avoiding.
Benefits
Provides a soft rose note
Citronellol contributes a gentle floral, rosy scent and is a staple in perfumes and floral-smelling skincare.
Found naturally in rose and geranium
It is a key component of rose and geranium essential oils, so botanically scented products often contain it.
Rounds out fragrance blends
Perfumers use it to soften and balance the top notes of a scent, and to mask base-ingredient odour.
Non-comedogenic
At fragrance-level concentrations it does not clog pores; sensitisation is the only skin-relevant concern.
How to use
Citronellol is not something you apply on purpose; you decide whether to accept scented products that contain it. Tolerant skin generally has no issue. If you have a fragrance allergy, eczema, or you rely on sensitising actives such as retinol, salicylic-acid or glycolic-acid, choose fragrance-free options instead. Store scented and floral-oil products away from heat and light and replace them when the smell changes, since oxidation raises the allergy risk. Patch test new products listing citronellol on the forearm before facial use.
Side effects
Most users have no reaction. In sensitised people citronellol can cause allergic contact dermatitis — an itchy, red rash at the site of contact that may appear a day or two after exposure. Risk is higher with leave-on products and with older, oxidised formulas. It is included in standard fragrance patch-test panels used by dermatologists.
Who should avoid it
Those with a known allergy to citronellol, rose or geranium fragrances, plus anyone with eczema, rosacea or a damaged barrier, should choose fragrance-free products. People combining several actives should keep fragrance exposure to a minimum.
Avoid combining with
Frequently asked questions
What is citronellol used for in skincare?
It is used purely as a fragrance ingredient for its soft, rosy scent. It has no treatment benefit for acne, hydration or ageing, so its only role is to make a product smell pleasant.
Is citronellol a common allergen?
It is one of the 26 fragrance allergens the EU requires to be labelled, but reactions are limited to a minority of people. Most users tolerate it without any problem.
Does citronellol clog pores or cause acne?
No. It is used in trace amounts and has a comedogenic rating of zero. Its only skin-relevant risk is allergic sensitisation, not clogged pores or breakouts.
Should I avoid citronellol if I have sensitive skin?
If your skin is reactive or you use strong actives, fragrance-free products are the safer choice. If your skin tolerates fragrance well, citronellol is generally not a concern.
Sources & further reading
Medical disclaimer
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