skinsafecheck Ingredient Checker

Evening Primrose Oil

Evening primrose oil (INCI name Oenothera Biennis Oil) is rated 2 to 3 on our list, a range whose top puts it in the moderate band, and the number is traced: Fulton 1989 graded it 3.

Like every rating here, it is for the raw ingredient tested alone, and a label does not print how much of it a product holds.

Is evening primrose oil comedogenic?

2–3 Moderate

Evening Primrose Oil is rated 2–3 on the comedogenic scale: our list gives it a range from 2 to 3, and the band follows the 3 at the top.

A plant oil rich in gamma-linolenic acid, used as an emollient. Fulton 1989 graded it 3 in the rabbit-ear test.

Comedogenic rating
2–3 out of 5 (a range on our list)
Band
Moderate: Borderline plugging in the rabbit-ear test. Worth a look in a leave-on product.
Where the number comes from
Traced to Fulton 1989. The section on who rated it prints each grade.
Composition
Natural Oil / Oils (High in linoleic acid)
Also written as
No common variants recorded
Where Evening Primrose Oil sits on the 0 to 5 comedogenic scale. Our list gives a range, so the whole range is drawn and the band follows the higher end. The papers we checked it against are under Sources we checked this rating against further down this page.

What a 2–3 means in practice

Three is the middle of the scale. Fulton 1989 counted 2 to 3 as borderline in the rabbit-ear test: some plugging of the follicles, short of a clear positive. Whether it matters depends on how high it sits on the label and whether the product stays on your skin.

Two things change what this number is worth. Ingredients are listed in descending order of concentration, so evening primrose oil near the top of a label matters far more than evening primrose oil at the bottom. And the rating describes the raw ingredient on its own. A 2006 review in the Journal of the American Academy of Dermatology found that a rating for a single ingredient does not reliably predict how a finished formula behaves on human skin. The full story of the scale is here.

Check a whole ingredient list

Who rated it

Our list gives evening primrose oil 2–3. These are the figures the published rabbit-ear studies we have read give it, as printed in each paper's table.

Paper Grade Tested as
Fulton 1989
rabbit ear, 10% in propylene glycol unless stated, two weeks
Grade 3 Tested as Evening primrose oil

Our list's lowest figure, 2, is lower than anything in these papers.

A grade is for the raw ingredient tested alone on a rabbit's ear, which reacts more readily than human skin. It says nothing about how much of it a product holds or what the rest of the formula does.

Fungal acne

Evening Primrose Oil matches rule 4, plant or animal oil or butter , on the fungal acne checker. A plant or animal oil, mostly triglycerides. The rule comes from lab studies of what Malassezia yeast can feed on, and it is not a verdict on any product.

What safety reviewers say

The rating above is about pore plugging in a rabbit-ear test. Whether evening primrose oil is safe to use in cosmetics is a separate question. Below is the conclusion of the Cosmetic Ingredient Review (CIR), a US expert panel, and what the EU ingredient database, CosIng, lists for it. We quote CIR's conclusion as written, read on 1 November 2026.

Cosmetic Ingredient Review (US)
In a 2017 review of 244 plant-derived fatty acid oils, evening primrose oil among them, the panel concluded they are “safe in the present practices of use and concentration described in this safety assessment”. Safety Assessment of Plant-Derived Fatty Acid Oils, 2017 (opens in a new tab)
What it does in a product (EU CosIng)
Listed as OENOTHERA BIENNIS OIL: skin conditioning (emollient). CosIng entry (opens in a new tab)
EU restrictions
None. CosIng shows no entry for it in the annexes of the EU Cosmetics Regulation.

CIR was set up in 1976 by the US cosmetics trade association, now the Personal Care Products Council, and the Council funds it. CIR states that its panel and review process are independent of the Council and the cosmetics industry. CIR's statement (opens in a new tab). The FDA does not approve cosmetic ingredients before they go on sale, except colour additives, and the companies that make and sell cosmetics are legally responsible for their safety. FDA's page (opens in a new tab).

What we make of this. CIR's conclusion does not grade pore plugging, so on its own it neither confirms nor contradicts the 2–3 on our list. A safety review looks at things like irritation, allergy and toxicity at the amounts products use, and the rating is only about pores, so read them side by side.

Common questions

Is evening primrose oil comedogenic?
Evening Primrose Oil is rated 2–3 on the comedogenic scale: our list gives it a range from 2 to 3, and the band follows the 3 at the top.
Is evening primrose oil non comedogenic?
No. Evening Primrose Oil is rated 2–3 on the comedogenic scale, which is the moderate band. That is a published rating for the ingredient rather than a verdict on any product containing it.
What is evening primrose oil's comedogenic rating?
2–3 out of 5 on our list. It is classed as Natural Oil / Oils (High in linoleic acid).

Sources we checked this rating against

  1. Kligman AM, Kwong T. “An improved rabbit ear model for assessing comedogenic substances.” British Journal of Dermatology, June 1979;100(6):699–702. (opens in a new tab) The rabbit-ear assay behind published 0 to 5 comedogenicity grades.
  2. Fulton JE Jr. “Comedogenicity and irritancy of commonly used ingredients in skin care products.” Journal of the Society of Cosmetic Chemists, November/December 1989;40(6):321–333. (opens in a new tab) Rabbit ear. Each ingredient at 10 percent in propylene glycol unless stated, applied five days a week for two weeks, and graded 0 to 5 from the width of the follicles, measured by micrometer and under the microscope. The paper counts 0 to 1 as not significant, 2 to 3 as borderline and 4 to 5 as positive. Some grades depended on the supplier of the raw material, and some oils were also tested refined.
  3. Draelos ZD, DiNardo JC. “A re-evaluation of the comedogenicity concept.” Journal of the American Academy of Dermatology, March 2006;54(3):507–512. doi:10.1016/j.jaad.2005.11.1058 (opens in a new tab) Tested finished products on the backs of six people and concluded that “Finished products using comedogenic ingredients are not necessarily comedogenic.”

The rating and description above are the ones this site publishes on its A–Z list. The papers above are the ones we checked it against, and the section on who rated it says whether any of them graded this ingredient.