Evening Primrose Oil (GLA) and Vitex (Chasteberry)
Each entry’s own grades, side by side. A grade says how strong the evidence is for one outcome — it does not rank one entry over the other.
Compound or practice
Evening Primrose Oil (GLA)
A GLA source popular for PMS, breast pain, and eczema — mostly modest or null on rigorous review.
Grade C2 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Compound or practice
Vitex (Chasteberry)
One of the better-supported botanicals for PMS and cyclical breast pain, working through prolactin.
Grade B2 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Graded in both
Outcomes are matched by name. Two entries can describe the same outcome in different words, so one listed further down may still be graded in the other.
No outcome has the same name in both entries. They may still overlap under different wording — read the two lists below.
Graded only in Evening Primrose Oil (GLA)
- PMS / breast pain Small effectEvidence grade C
- Eczema Trivial effectEvidence grade D
Graded only in Vitex (Chasteberry)
- PMS symptoms Moderate effectEvidence grade B
- Cyclical breast pain Moderate effectEvidence grade B
Conditions
- PMSEvening Primrose Oil (GLA): May improveEvidence grade CVitex (Chasteberry): ImprovesEvidence grade B
Only in Evening Primrose Oil (GLA)
None.
Only in Vitex (Chasteberry)
None.
What each entry says about the other
Neither entry records anything about the other. That is not evidence that they do not interact — only that neither entry says.
Both columns are read from the entries as they stand in this library. A comparison is not advice to take either one, and it is no substitute for a clinician who knows the person.