PE-22-28

What PE-22-28 does

PE-22-28 is a seven-amino-acid peptide shortened from spadin, studied for mood effects in mice and cells. No human trial was found; human benefits, dosing and safety remain unknown. It affects TREK-1, a channel that helps control nerve-cell activity. Online reports describe mood changes and unwanted effects; product quality is unverified.

• In studies in mice, it changed behavior linked to mood; whether it helps people has not been tested. (animal)
• People report better mood, more motivation and less anxiety, though some felt worse or noticed nothing. (Reported by users)
• People report clearer thinking and an easier time starting tasks; no human trial has tested this. (Reported by users)

Uses in the sources

• People report using it for low mood and anxiety. These reports do not establish benefit in depression or anxiety disorders. (Reported by users) (source)
• Users describe clearer thinking and easier task initiation. No human cognition trial was found. (Reported by users) (source)
• A clinician review mentions it as a possible mental-health adjunct. It reports no PE-22-28 patient outcomes or dose. (Clinician-published) (source)

PE-22-28 dosage

Typical reported dose: 400 mcg once a day

• 400 mcg daily injection: 400 mcg once daily once daily, under the skin. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)
• 200 mcg, 8 weeks on and 2 off: 200 mcg once daily once daily on treatment weeks, under the skin. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)
• 300-600 mcg nasal report: Started at 300 mcg/day; later 600 mcg/day daily; distribution through the day not stated, nasal spray. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)
• 400-1000 mcg on use days: 400-1000 mcg/day when used variable; some days skipped, nasal spray. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)
• 160 mcg nasal blend, weekdays: 160 mcg PE-22-28 total per use day two sprays total daily, 5 days/week, nasal spray. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)
• 800 mcg split-dose report: 400 mcg, then 400 mcg 6 hours later; one reported day two doses in one day, 6 hours apart, under the skin. Reported by users, rare report. Studied in: Adults posting personal use reports online; diagnosis and product identity unverified. (source)

These are doses reported in labels, trials or user reports, not a personal plan. Check the source behind each one.

Work out syringe units with the dosing calculator

How to mix PE-22-28

Comes as: Powder vials reported by users, Nasal spray reported by users.

Mixed with: Users mention bacteriostatic water. No validated human diluent or nasal formulation was found..

Common vial sizes: 8, 10 mg. Common water amounts: 2, 3 mL.

• Vial sizes and 2-3 mL volumes come from user discussions, not formulation studies.
• One user described 8 mg with 3 mL bacteriostatic water; another discussed 10 mg vials and typical 2-3 mL dilution.
• A post suggesting 5 mL was advice, not confirmed use. Nasal pump output and absorption are unvalidated.

Before mixing: No validated PE-22-28 storage temperature or shelf-life was found.

After mixing: No validated mixed-solution expiry, refrigerator stability or freeze-thaw data was found.

PE-22-28 side effects and risks

Reported side effects

• Tiredness or excess sleep: User reports include tiredness after 400 mcg twice in a day; no reliable rate., moderate. Avoid driving if drowsy; seek review if symptoms persist. (source)
• Irritability, restless sleep or overstimulation: One 300 mcg injection report and one 200 400 mcg/day nasal report; no reliable rate., moderate. Stop PE-22-28 and seek review for persistent or worsening symptoms. (source)
• Nausea and poor concentration with phenelzine: One self report after 800 mcg intranasally; serotonin syndrome was not clinically confirmed., moderate. Stop the unapproved peptide and seek assessment; do not self-adjust prescribed antidepressants. (source)
• Worse mood or no improvement: A commenter reported feeling worse after about 3 weeks of 500 mcg injections. Frequency is unknown., moderate. Seek mental-health review; use urgent care for suicidal thoughts or inability to stay safe. (source)
• Allergy or infection from an unregulated product: General peptide product risks; PE 22 28 specific rates are unknown., serious. Seek immediate care for breathing problems; prompt care for spreading redness or fever. (source)

Stop and get help if

• Suicidal thoughts, a suicide plan, or inability to stay safe: Get urgent crisis help. In the US call 988; call 911 for immediate danger. Elsewhere use local emergency services.
• Confusion or agitation with fever, sweating, tremor or muscle jerks: Seek emergency care, especially with antidepressants or MAO inhibitors. PE-22-28-related serotonin toxicity is unproven.
• Trouble breathing, throat or tongue swelling, or collapse: Stop exposure and call emergency services now. Use prescribed emergency adrenaline if available.
• Spreading hot, painful redness or fever after an injection: Stop injections and seek prompt medical assessment for possible infection.

Who should avoid it

• pregnant: Precaution: fetal and pregnancy safety have not been studied in humans.
• breastfeeding: Precaution: transfer into milk and effects on a nursing infant are unknown.
• tryingToConceive: Precaution: human fertility and reproductive safety data are absent.
• under18: Precaution: no pediatric dosing or developmental safety evidence was found.
• depressionOrSuicidalThoughts: No human antidepressant trial supports replacing established care. New suicidal thoughts need urgent assessment.
• psychiatricCondition: Mood worsening and overstimulation appear in user reports. Psychiatric effects and drug interactions are unstudied.
• heartCondition: Precaution: TREK-1 has heart functions. A negative cell hERG test does not establish cardiac safety in people.
• seizureDisorder: Precaution: TREK-1 affects brain excitability. Human seizure risk is unknown.
• kidneyDisease: Precaution: human clearance and dose adjustment in kidney disease are unknown.
• liverDisease: Precaution: human metabolism and dose adjustment in liver disease are unknown.
• testedAthlete: The 2026 S0 rule covers unapproved pharmacological substances at all times.
• other: Avoid re-exposure after a serious allergic reaction to the product or its ingredients.

Interactions

• MAO inhibitors: No interaction trial. One phenelzine user reported nausea and poor concentration during PE-22-28 escalation; toxicity was not confirmed.
• SSRIs, SNRIs and other serotonin-active drugs: Possible additive brain effects are untested. Parent spadin increases serotonin-neuron firing in mice; a different mechanism does not prove compatibility.
• Insulin and sulfonylureas: Theoretical interaction: mini-spadin affects insulin-making cells in vitro. Human blood-sugar effects and low-sugar risk are unknown.
• Other brain-active peptides: Combinations are reported online without interaction or safety trials. Duplicate spadin analogues may also have different identities.

Product quality risks

• No peer-reviewed market-testing study of PE-22-28 products was found.
• General peptide warnings describe wrong amounts, unknown ingredients, microbes and endotoxin. PE-22-28-specific rates are unknown.
• A study of three online semaglutide samples found 28.56%-38.69% excess content and endotoxin in one. These are not PE-22-28 measurements.

What to expect

Three PE-22-28 or mini-spadin papers studied mice or cells. Two studies of the longer peptide spadin give background; no human dosing study or registered trial was found.

Key studies

• PE-22-28 in mice and cells: PE-22-28 changed mouse behavior and cell-growth markers; human benefit remains untested. (source)
• Mini-spadin after experimental stroke: Mini-spadin affected recovery and mood-like behavior in stroke-injured mice. (source)
• Mini-spadin in insulin-making cells: Mini-spadin protected cultured insulin-making cells; this is not evidence for diabetes treatment in people. (source)
• Parent spadin discovery: Parent spadin linked TREK-1 inhibition to antidepressant-like effects in mice. (source)
• Parent spadin: assay-dependent effects: Parent spadin effects depended on channel activation and experimental conditions. (source)

PE-22-28 FAQ

• Is PE-22-28 FDA-approved? No FDA approval or label found. No compound-specific warning letter located. An unapproved research product has no FDA-approved prescribing instructions.
• How do people take it? Under the skin, once daily. Source: reported by users, not an established dose.
• What's the difference between PE-22-28 and Selank? PE-22-28: an experimental mood peptide studied in mice, with no human trials found. Selank: a Russian nasal anxiety peptide with uncertain long-term benefit and safety. Why people pair them: users combine nasal formulations hoping for calmer mood and less anxiety. No human trial has tested this combination.
• Can I take it with Selank? Users combine nasal formulations hoping for calmer mood and less anxiety. No human trial has tested this combination. Reported benefit cannot be assigned to either ingredient; combination safety and spray delivery are untested. Source: reported by users. Ask a doctor before combining anything.
• Is it banned in sport? Yes. It is banned in and out of competition (WADA 2026). Falls under the rule for unapproved pharmacological substances. This applies the S0 rule; PE-22-28 is not named individually.
• How long does a mixed vial last? No validated mixed-solution expiry, refrigerator stability or freeze-thaw data was found.