library.onepin.app/orexin-b Peptide Education Library
Education only, not medical advice 21+ Every dose is an example to finalize with a licensed provider

OnePin Peptide Library · Cognitive & Mood

Cognitive & Mood Endogenous Hypothalamic Neuropeptide Not FDA-approved · investigational

Orexin B

Hypocretin-2 · OX-B

Endogenous Hypothalamic NeuropeptideOX2R-Selective AgonistInvestigational Narcolepsy TherapyResearch Chemical (no FDA approval)

Orexin B (Hypocretin-2) is the second of two endogenous orexin peptides produced by lateral hypothalamic neurons. It is a 28-amino-acid peptide with OX2R-selective binding (vs Orexin A which binds OX1R and OX2R equally). The OX2R selectivity makes Orexin B more focused on the histaminergic wake-promotion pathway (tuberomammillary nucleus) and less involved in OX1R-mediated reward/arousal pathways.

Quick Start
Route
Intranasal
Start low
Per protocol
Frequency
Investigational
Timing
Independent

Intranasal route. Refrigerate. Disulfide-containing peptide.

Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.

Tiered Protocols · lowest first
Quick Start
Conservative start
Per protocol · Intranasal · Investigational
Lowest starting point. Hold about a week to assess tolerance before stepping up.
Per protocol
Investigational
Expert
Wakefulness Support
100-200 mcg · Nasal · As needed
animal study · Sakurai et al. 1998 (Cell, 92:573-585)
100-200 mcg
As needed
Reconstitution CalculatorU-100
050100u
Draw to
units
01

How it works

Orexin B binds primarily to OX2R with ~10x greater affinity than for OX1R, distinguishing it from Orexin A's dual-receptor binding profile:

OX2R-Selective Wake Promotion

OX2R is the dominant orexin receptor on histaminergic tuberomammillary nucleus (TMN) neurons that drive wakefulness. Selective OX2R agonism is the most-targeted pathway for narcolepsy therapy.

Reduced OX1R Effects

Lower OX1R activation means less effect on dopaminergic VTA reward pathways and locus coeruleus arousal compared to Orexin A. This may reduce cardiovascular and reward-related side effects.

Same Therapeutic Application

Like Orexin A, candidate narcolepsy replacement therapy. The OX2R selectivity may give Orexin B a cleaner clinical profile in principle.

Disulfide-Containing

Like Orexin A, contains intramolecular disulfide bonds - chemistry-incompatible with copper-conjugated peptides.

Same BBB Challenge

Intact peptide poorly crosses BBB. Intranasal route bypasses this for clinical research.

02

What to expect

Early
Days 1–7

Acute wakefulness within 15-30 min intranasal.

Mid
Weeks 2–4

Effects fade with plasma clearance.

Later
Weeks 4–12

No long-term effects characterized.

03

Evidence

HumanPresent
AnimalPresent
In-vitroPresent
2000Hypocretin-1 (orexin-A) deficiency in human narcolepsy · Nishino S et al, The Lancet ↗peer reviewed
2009Orexin/hypocretin: a neuropeptide at the interface of sleep, energy homeostasis, and reward system · Tsujino N, Sakurai T, Pharmacological Reviews ↗review
2014Selective orexin receptor agonists - emerging therapy for narcolepsy · Sakurai T, Nature Reviews Neurology ↗review
04

Interactions & stacking

What's safe to combine, and what belongs in a separate pin.

Keep separate

05

Side effects & safety

Commonly reported

  • Nasal irritation (intranasal)
  • Mild stimulation

Less common & notes

  • Cleaner side-effect profile theoretically vs Orexin A due to OX2R selectivity.
  • Long-term safety not characterized.
06

Pharmacokinetics

Illustrative plasma concentration · 24 h
Half-life
~30-60 min plasma
Peak · Tmax
15-30 min intranasal
Elimination
1-3 hours wakefulness
Activity
1-3 hours per dose

Storage. Refrigerate. Light-sensitive. Disulfide-containing - keep cold.

07

Regulatory status

Not FDA-approved. Research chemical only.

Put it to work

Calculate, log & track

Open Orexin B straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.

Open Orexin B in the app →

Go deeper

The guide & community

The complete Orexin B walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.

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