Androstadienone — Safety, Research, Risks & Legal Status

Not medical advice. Androstadienone is discussed here for informational and harm-reduction purposes only. We do not endorse use, and any dosing context is informational, not a protocol.

Also known as	Androsta-4,16-dien-3-one; 16-androstene class steroid; CAS 4075-07-4
Category	Research Chemical
CAS Number	4075-07-4
Molecular Formula	C19H26O; MW 270.4 g/mol
Endogenous Source	Male axillary secretions; smaller amounts in saliva and skin oils
Regulatory Class	Not FDA-approved; not scheduled; sold as cosmetic/fragrance ingredient
Related Clinical Compound	Fasedienol (VistaGen PH94B) - same proposed mechanism; Phase 3 primary endpoint failed 2025
Pheromone Status	Contested; demonstrable behavioral/neural effects in controlled studies but true pheromone classification unresolved as of 2024
US legal status	Not a controlled substance in the United States. Androstadienone is not FDA-approved for any medical indication and carries no ATC code. It is sold over-the-counter as a cosmetic or fragrance ingredient under no prescription or clinical pathway. It should not be confused with 4-androstenedione, an oral anabolic steroid supplement banned by the FDA in 2004. The structurally related investigational compound fasedienol (VistaGen Therapeutics) held IND status but failed its Phase 3 primary endpoint in 2025 and is not approved.

What is Androstadienone?

Androstadienone is an endogenous C19 steroid (molecular formula C19H26O; MW 270.4 g/mol) naturally present in male axillary secretions and in smaller amounts in saliva and skin oils. It is synthesized from androstadienol and can be converted by 5-alpha-reductase to androstenone. It is classified as a putative human pheromone - a designation that remains scientifically contested. It has no androgenic or anabolic activity and is distinct from testosterone-pathway steroids. Its primary research interest lies in potential modulatory effects on social cognition, emotional attention, and behavior through peripheral nasal chemosensory pathways rather than conscious olfaction.

How it works

Androstadienone is proposed to activate peripheral nasal chemosensory neurons (not classic olfactory receptors in the conscious sense) and to modulate attention and social cognition via limbic and amygdala pathways. fMRI evidence in human studies shows hypothalamic activation in women and modulation of thalamic fear processing. The compound appears to attune cognition specifically toward emotional and social information. Whether this constitutes true pheromone activity - defined as subconscious, involuntary behavioral triggering - remains unresolved. It does not bind androgen receptors at physiologically relevant concentrations and produces no known anabolic or androgenic effects.

Background & history

Androstadienone attracted scientific attention in the late 1990s and 2000s as part of broader interest in putative human pheromones. Multiple peer-reviewed studies from approximately 2000 through the mid-2020s examined its effects on emotional face processing, aggression, cooperative behavior, and stress responses. Commercial interest led to its inclusion in pheromone-marketed fragrances, a use unsupported by clinical evidence. The most significant translational effort was VistaGen Therapeutics' development of fasedienol (PH94B), a synthetic analog delivered as a nasal spray, which entered Phase 3 trials for social anxiety disorder. The PALISADE-3 trial (NCT06809179) reported topline failure of the primary endpoint in 2025, raising questions about clinical translation of the chemosensory mechanism. No pharmaceutical development pathway currently exists for androstadienone itself.

What the research says

Multiple peer-reviewed human studies have been conducted with androstadienone. Demonstrated findings in controlled settings include: increased attention to emotional and angry facial expressions; sex-dependent modulation of aggression (reduced reactive and proactive aggression in men; increased reactive aggression in women); increased cooperative behavior in economic decision tasks independent of baseline testosterone; and hypothalamic activation on fMRI in female participants. These are real, replicated experimental findings under controlled conditions. However, the literature as of 2024 characterizes androstadienone's pheromone status as inconclusive - demonstrable effects on cognition and neural processing do not by themselves establish classic pheromone status. A 2024 ScienceDirect review explicitly concluded more research is needed. The 2025 Phase 3 failure of fasedienol, a related compound designed to exploit the same chemosensory pathway for social anxiety, underscores the gap between laboratory findings and clinical efficacy. No human clinical trials have been conducted on androstadienone itself for any therapeutic indication. Animal data show sex-specific odor communication effects consistent with mammalian pheromone biology. Overall evidence base: limited to moderate, human behavioral/neuroimaging data exist but no controlled clinical trials and no approved indication.

Reported effects

Modulates attention toward emotional and social information in controlled human studies
Reduces reactive and proactive aggression in men (sex-dependent; opposite direction observed in women in some studies)
Increases cooperative behavior in male participants in economic decision tasks
Activates hypothalamus on fMRI in female participants; modulates thalamic fear-processing circuits
May attune cognition to emotional stimuli rather than producing broad mood or arousal effects
Effects are subtle, context-dependent, and demonstrated primarily in controlled laboratory settings - generalizability to real-world behavior is unestablished

Dosing & administration (informational)

Literature studies have used a range of topical concentrations applied to the upper lip or skin, typically in ethanol vehicle. Specific concentrations varied across published studies and are described in those publications for research documentation purposes only. This information is not a dosing protocol. There is no established therapeutic dose, no approved clinical use, and no validated administration route for any human health indication. Consult a licensed clinician before any use.

This is general research/context information, not medical advice or a recommended protocol.

Safety & side effects

Minimal published toxicology; topical and fragrance-concentration use is generally considered low-risk based on available data
No documented systemic toxicity or endocrine disruption at typical exposure levels; does not have androgenic or anabolic activity
Possible mild skin irritation at high concentrations, concentration-dependent and rarely reported
Olfactory fatigue reported with repeated or high-dose exposure
Should not be ingested or applied to mucous membranes
No reproductive or developmental safety data in humans
Long-term safety at above-fragrance concentrations has not been studied; absence of evidence is not evidence of safety

Drug & supplement interactions

N
o
p
h
a
r
m
a
c
o
k
i
n
e
t
i
c
d
r
u
g
i
n
t
e
r
a
c
t
i
o
n
d
a
t
a
e
x
i
s
t
f
o
r
a
n
d
r
o
s
t
a
d
i
e
n
o
n
e
i
n
h
u
m
a
n
s
.
A
s
a
s
t
e
r
o
i
d
m
e
t
a
b
o
l
i
z
e
d
v
i
a
5
-
a
l
p
h
a
-
r
e
d
u
c
t
a
s
e
p
a
t
h
w
a
y
s
,
t
h
e
o
r
e
t
i
c
a
l
i
n
t
e
r
a
c
t
i
o
n
s
w
i
t
h
5
-
a
l
p
h
a
-
r
e
d
u
c
t
a
s
e
i
n
h
i
b
i
t
o
r
s
(
f
i
n
a
s
t
e
r
i
d
e
,
d
u
t
a
s
t
e
r
i
d
e
)
a
r
e
c
o
n
c
e
i
v
a
b
l
e
b
u
t
u
n
s
t
u
d
i
e
d
.
N
o
i
n
t
e
r
a
c
t
i
o
n
d
a
t
a
w
i
t
h
S
S
R
I
s
,
a
n
x
i
o
l
y
t
i
c
s
,
o
r
o
t
h
e
r
p
s
y
c
h
o
a
c
t
i
v
e
c
o
m
p
o
u
n
d
s
h
a
v
e
b
e
e
n
p
u
b
l
i
s
h
e
d
.
T
h
e
a
b
s
e
n
c
e
o
f
i
n
t
e
r
a
c
t
i
o
n
d
a
t
a
s
h
o
u
l
d
n
o
t
b
e
i
n
t
e
r
p
r
e
t
e
d
a
s
s
a
f
e
t
y
.

Who should avoid it

Ingestion or mucosal application
Use in individuals with known steroid hypersensitivity or skin conditions affecting the application site
Combination with other steroid-pathway modulators without medical supervision
Reliance on pheromone-marketed commercial products as evidence-based interventions
Extrapolating laboratory behavioral findings to expected real-world social or sexual outcomes
Use as a substitute for evaluated treatments in anxiety, aggression, or social cognition disorders

How it is commonly combined

No evidence-based stacking data exist. Androstadienone is not used in any validated clinical protocol. Combining it with other neuroactive or steroid-pathway compounds is speculative and unstudied.

Legal & regulatory. Not a controlled substance in the United States. Androstadienone is not FDA-approved for any medical indication and carries no ATC code. It is sold over-the-counter as a cosmetic or fragrance ingredient under no prescription or clinical pathway. It should not be confused with 4-androstenedione, an oral anabolic steroid supplement banned by the FDA in 2004. The structurally related investigational compound fasedienol (VistaGen Therapeutics) held IND status but failed its Phase 3 primary endpoint in 2025 and is not approved.

Quality & harm reduction

A
n
d
r
o
s
t
a
d
i
e
n
o
n
e
i
s
p
r
o
d
u
c
e
d
b
y
m
u
l
t
i
p
l
e
c
h
e
m
i
c
a
l
s
u
p
p
l
i
e
r
s
(
i
n
c
l
u
d
i
n
g
C
l
e
a
r
s
y
n
t
h
,
S
a
n
t
a
C
r
u
z
B
i
o
t
e
c
h
n
o
l
o
g
y
,
a
n
d
v
a
r
i
o
u
s
C
D
M
O
m
a
n
u
f
a
c
t
u
r
e
r
s
)
a
s
a
r
e
s
e
a
r
c
h
c
h
e
m
i
c
a
l
.
N
o
p
h
a
r
m
a
c
e
u
t
i
c
a
l
-
g
r
a
d
e
G
M
P
-
c
e
r
t
i
f
i
e
d
h
u
m
a
n
-
u
s
e
p
r
o
d
u
c
t
e
x
i
s
t
s
.
P
u
r
i
t
y
a
n
d
i
d
e
n
t
i
t
y
s
h
o
u
l
d
b
e
v
e
r
i
f
i
e
d
b
y
c
e
r
t
i
f
i
c
a
t
e
o
f
a
n
a
l
y
s
i
s
w
i
t
h
H
P
L
C
a
n
d
N
M
R
w
h
e
n
u
s
e
d
i
n
r
e
s
e
a
r
c
h
c
o
n
t
e
x
t
s
.
C
o
m
m
e
r
c
i
a
l
p
h
e
r
o
m
o
n
e
f
r
a
g
r
a
n
c
e
p
r
o
d
u
c
t
s
c
o
n
t
a
i
n
i
n
g
a
n
d
r
o
s
t
a
d
i
e
n
o
n
e
a
r
e
n
o
t
i
n
d
e
p
e
n
d
e
n
t
l
y
v
e
r
i
f
i
e
d
f
o
r
c
o
n
c
e
n
t
r
a
t
i
o
n
a
c
c
u
r
a
c
y
o
r
p
u
r
i
t
y
a
n
d
a
r
e
n
o
t
s
u
b
j
e
c
t
t
o
F
D
A
d
r
u
g
m
a
n
u
f
a
c
t
u
r
i
n
g
s
t
a
n
d
a
r
d
s
.

Safer, legal alternative we recommend

Creatine Supreme. For supporting muscle mass and strength, creatine monohydrate is the most evidence-backed legal option, with decades of safety data - ours ships from the Peptropix line.

See our recommended pick

Find Androstadienone →

Know your numbers before you research

Order your own bloodwork online — hormone, metabolic and inflammation panels, no doctor visit needed. Know your baselines before and during any protocol. Independent bloodwork is the cheapest insurance there is.

Get tested with Ulta Lab Tests →

Frequently asked questions

Is androstadienone a proven human pheromone?

No. Its pheromone status remains contested. Multiple controlled studies have demonstrated effects on emotional attention, aggression, and cooperative behavior, but the scientific community has not reached consensus that these effects meet the definition of classic pheromone activity - which requires subconscious, involuntary behavioral triggering. A 2024 review explicitly called for more research before drawing firm conclusions.

Does androstadienone have anabolic or androgenic effects?

No. Despite being a steroid structurally, androstadienone does not have meaningful androgenic or anabolic activity. It is categorically distinct from testosterone-pathway steroids and from the banned supplement 4-androstenedione.

What happened with fasedienol, and does that affect androstadienone?

Fasedienol (PH94B), developed by VistaGen Therapeutics as a nasal spray for social anxiety disorder, failed its primary endpoint in the PALISADE-3 Phase 3 trial in 2025. Fasedienol was designed to exploit the same proposed nasal chemosensory mechanism as androstadienone. Its failure suggests significant caution about translating androstadienone's laboratory findings to clinical therapeutic efficacy, though the two compounds are not identical.

What is the recommended dose of androstadienone?

There is no established or recommended dose for any human health indication. Published research studies describe various concentrations used in controlled experimental settings, but these are not clinical protocols. Consulting a licensed clinician is necessary before any use.

Is androstadienone legal in the United States?

Yes, it is not a controlled substance and is not FDA-banned. It is legally sold in cosmetic and fragrance products. However, it is not FDA-approved for any medical use and should not be represented as a drug or therapeutic agent.

Are the behavioral effects of androstadienone the same for men and women?

No. Published studies indicate sex-dependent effects. For example, androstadienone has been found to reduce reactive and proactive aggression in men while increasing reactive aggression in women in some studies. Effects on emotional attention and hypothalamic activation have also shown sex-specific patterns. The mechanism behind these differences is not fully established.

References & further reading

PubMed: androstadienone pheromone cognition emotional (search returns multiple studies 2009-2024, including PMID 19000767)
PubMed: androstadienone modulates human aggression sex-dependent (PMC9960015 / PMID 36690256)
PubMed: fasedienol social anxiety disorder Phase 3
ClinicalTrials.gov: NCT06809179 (PALISADE-3 fasedienol VistaGen Phase 3)
PubMed: is androstadienone human male pheromone review 2024