NSI-189 — Safety, Research, Risks & Legal Status

Not medical advice. NSI-189 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	NSI-189 phosphate, benzylpiperazine derivative
Category	Research Chemical
phase_2_trial	One small human trial for depression was initiated but not completed
neurogenesis_focus	Uniquely designed to promote new neuron growth rather than monoamine modulation
discontinued	Development halted; no Phase 3 trials; no FDA approval achieved
US legal status	Not FDA-approved. NSI-189 phosphate is a proprietary compound previously in clinical development for depression by Neuralstem, Inc. Sold as a research chemical online; not scheduled, but regulatory status for human use is undefined.

What is NSI-189?

NSI-189 is a synthetic benzylpiperazine compound designed to promote neurogenesis (growth of new neurons) in the hippocampus. It is believed to work via mechanisms independent of monoamine reuptake inhibition.

How it works

Proposed to promote neurogenesis in the hippocampus via mechanisms distinct from monoamine signaling. Theoretical mechanisms involve growth-factor expression or neural stem-cell proliferation.

Background & history

Developed by Neuralstem, Inc. as a novel antidepressant targeting neurogenesis. Underwent Phase 2 clinical trials for depression in the early 2010s; development stalled without Phase 3 advancement. Now exists only in research-chemical supply.

What the research says

A small Phase 2 trial in depression patients reported improvements in mood. Animal studies show neurogenesis in the hippocampus. However, clinical evidence is limited to one incomplete human trial. The compound did not advance to Phase 3, and independent replication is absent.

Reported effects

Studied in small human trial for mood elevation in depression
Animal studies show potential for increasing hippocampal neurogenesis
Preclinical research suggests potential cognitive enhancement via neurogenic mechanisms
Reported anecdotal improvements in mood and motivation by users, but no controlled evidence in humans

Dosing & administration (informational)

One incomplete Phase 2 trial reported doses, but trial halted before publication of full results. Animal studies use wide dose ranges not applicable to human safety.

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

Safety & side effects

Limited human safety data from one small incomplete trial; long-term effects unknown
Animal toxicology studies are minimal; organ-specific toxicity is not well-characterized
Unknown interactions with other compounds and medications
Quality of research-chemical suppliers is unverified; contamination risk is high
Using a compound with only one small human study carries substantial unknown risk

Drug & supplement interactions

Unknown; limited human pharmacokinetic data
Potential effects on neurogenesis pathways (interaction with neurotrophic agents unclear)
Unknown interaction with antidepressants or mood-altering substances

Who should avoid it

Human use without medical supervision (single incomplete trial only)
Assuming Phase 2 safety data generalizes to long-term use
Combining with other experimental neurogenic compounds (effects unknown)
Injection or parenteral use (bioavailability and toxicity not characterized)

How it is commonly combined

Stacking with other experimental nootropics or neurogenic agents is speculative and carries unknown multiplicative risks.

Legal & regulatory. Not FDA-approved. NSI-189 phosphate is a proprietary compound previously in clinical development for depression by Neuralstem, Inc. Sold as a research chemical online; not scheduled, but regulatory status for human use is undefined.

Quality & harm reduction

S
e
e
k
t
h
i
r
d
-
p
a
r
t
y
C
o
A
f
o
r
p
u
r
i
t
y
a
n
d
i
d
e
n
t
i
t
y
;
N
S
I
-
1
8
9
s
o
u
r
c
e
s
a
r
e
r
a
r
e
a
n
d
o
f
t
e
n
u
n
t
e
s
t
e
d
.
P
r
e
f
e
r
s
u
p
p
l
i
e
r
s
w
i
t
h
t
r
a
n
s
p
a
r
e
n
t
s
y
n
t
h
e
s
i
s
d
o
c
u
m
e
n
t
a
t
i
o
n
a
n
d
c
o
n
s
i
s
t
e
n
t
b
a
t
c
h
a
n
a
l
y
s
i
s
.

Lab testing & harm-reduction tools

If you are going to research a compound, verifying identity and purity is the single most protective step. Independent analytical testing and sterile-handling supplies reduce risk.

Compare testing options

Frequently asked questions

Was NSI-189 approved by the FDA?

No. NSI-189 underwent early clinical trials but did not complete FDA approval. Development was halted.

What evidence exists that NSI-189 increases neurogenesis in humans?

Animal studies strongly suggest neurogenic effects. A small human trial showed mood improvements, but whether neurogenesis occurs in humans is not proven.

Why is NSI-189 sold online if it is not approved?

NSI-189 is marketed as a research chemical by underground suppliers. Its regulatory status in the US is ambiguous, and enforcement is inconsistent.

Could NSI-189 treat depression?

One small trial suggested mood benefits, but the trial was incomplete and not published in full. Evidence is too limited to support clinical use.

References & further reading

N
e
u
r
a
l
s
t
e
m
P
h
a
s
e
2
d
e
p
r
e
s
s
i
o
n
t
r
i
a
l
(
i
n
c
o
m
p
l
e
t
e
d
a
t
a
)
;
a
n
i
m
a
l
h
i
p
p
o
c
a
m
p
a
l
n
e
u
r
o
g
e
n
e
s
i
s
s
t
u
d
i
e
s
;
n
e
u
r
o
t
r
o
p
h
i
c
-
f
a
c
t
o
r
r
e
s
e
a
r
c
h
;
o
n
l
i
n
e
r
e
s
e
a
r
c
h
-
c
h
e
m
i
c
a
l
c
o
m
m
u
n
i
t
y
r
e
p
o
r
t
s
.