Rosemary & Lavender
Rosemary and lavender oil are plant-derived essential oils commonly used in personal care and wellness products. They are often included in shampoos, scalp treatments, and skincare products for their fragrance and potential soothing or conditioning properties. Rosemary is frequently associated with scalp stimulation, while lavender is commonly used for its calming scent and skin-friendly qualities.
-
This page summarizes anecdotal reports and community observations, not medical evidence. Reports may be incomplete, biased or inaccurate and are not medical advice or recommendations. “Risk” here refers to how frequently severe or prolonged symptom worsening is reported, not to proven causation or population-wide probability. Individual responses vary widely, and absence of issues in some users does not rule out significant reactions in others.
-
Within PFS/PSSD/PAS communities, rosemary and lavender oils are discussed in relation to their potential interactions with androgen signaling pathways and endocrine receptor activity. Rosemary oil has been studied in androgenetic alopecia; one randomized comparative trial reported that topical rosemary oil performed similarly to 2% minoxidil over six months. Separately, rosemary extracts have shown 5-alpha-reductase–related activity in experimental settings, which is one reason rosemary appears in "DHT-friendly" hair formulations—though lab findings don't always translate directly to meaningful whole-body hormone effects in humans from topical use. Lavender oil is more often discussed in relation to endocrine signaling: a NEJM case series described prepubertal gynecomastia associated with repeated topical exposure to lavender/tea tree products that improved after stopping, and in-vitro work has suggested weak estrogenic and anti-androgenic activity for certain components, while later reviews argue human evidence remains limited and not definitive. These mechanisms may interact with pathways involving 5-alpha-reductase activity, androgen receptor signaling, or endocrine receptor activity that are often discussed in relation to PFS / PSSD / PAS. (pubmed) (nejm)
-
Reports of Mostly Temporary Symptom Flares (for PFS/PSSD/PAS):
Among individuals who already have PFS/PSSD/PAS, rosemary and lavender oils/extracts are occasionally mentioned in community reports as preceding symptom flares. Concerns typically focus on hormone-adjacent signaling (rosemary in a DHT/5-alpha-reductase context; lavender in an endocrine receptor-activity context) and on the fact that essential oils can deliver concentrated bioactive compounds through repeated topical exposure. Many reports describe effects that improve after stopping, but some individuals describe longer-lasting destabilization, especially with frequent use of concentrated oils or leave-on scalp products.
For individuals without these conditions, rosemary and lavender oils are widely used in cosmetics and are generally tolerated, though sensitivity reactions and endocrine concerns have been raised in specific contexts (particularly repeated exposure in case reports).
Evidence basis: Limited clinical hair-loss trial data for rosemary; mechanistic/in-vitro endocrine findings for lavender; case reports; anecdotal reports (online forums, self-reports); no controlled studies examining PFS/PSSD/PAS-specific outcomes.
-
Public comments reflect individual experiences and opinions. They are not medical advice and may not be accurate or representative.