Side-by-side · Research reference

HGH 191AAvsVilon

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AFDA-ApprovedHUMAN-REVIEWED0/75 cited

BAnimal-StrongHUMAN-REVIEWED13/49 cited

HGH 191AA

Recombinant hGH · FDA-Approved

0.024–0.034 mg/kg/dayPediatric GHD dose

2–4 hoursPlasma half-life

191 AASequence length

SQ · Daily · Evening preferred

Vilon

Khavinson Bioregulator · Dipeptide

2 AADipeptide

T-helperStimulatesLinkova 2011

MouseModel basisKhavinson 2002

Literature lacks standardised clinical route

01Mechanism of Action

Parameter

HGH 191AA

Vilon

Primary target

Growth hormone receptor (GHR) — JAK2/STAT5 pathway

Immune cell differentiation pathways, chromatin modification

Pathway

GHR activation → JAK2/STAT5 → liver IGF-1 synthesis + direct metabolic effects

Vilon → Thymocyte sphingomyelinase activation → T-helper & cytotoxic T-cell differentiation; epigenetic suppression of aging markers (CCL11, HMGB1)

Downstream effect

Linear growth, lipolysis, protein synthesis, nitrogen retention, carbohydrate metabolism modulation

Enhanced T-cell differentiation (CD4+, CD8+, B-cells), thymocyte proliferation, modulated IL-1β comitogenic activity, proposed chromatin decondensation in aged lymphocytesLinkova 2011 Khavinson 2002 Lezhava 2023

Feedback intact?

No — exogenous GH bypasses hypothalamic-pituitary axis, suppresses endogenous pulsatility

Unknown — no HPA/HPG axis data

Origin

Recombinant DNA technology — 191 AA, identical to pituitary hGH, no methionyl residue

Synthetic dipeptide derived from Khavinson thymic peptide extraction studies (Thymalin fraction)Morozov 1997

Antibody development

Rare — <2% develop binding antibodies, typically non-neutralizing

—

02Dosage Protocols

Parameter

HGH 191AA

Vilon

Pediatric GHD

0.024–0.034 mg/kg/day SQ

6–7× per week dosing typical. Brand-specific ranges.

—

Adult GHD

0.004–0.016 mg/kg/day SQ

Start low, titrate based on IGF-1 levels.

—

Turner syndrome

0.045–0.050 mg/kg/day SQ

—

Idiopathic short stature

0.037 mg/kg/day SQ

—

AIDS wasting

0.1 mg/kg/day SQ (high-dose)

Short-term indication. Monitor glucose.

—

Frequency

Once daily, typically evening

Evening administration mimics physiological GH pulse.

Unknown — literature does not specify chronic administration protocols

Evidence basis

FDA-approved / decades of RCT data

Mouse / in vitro only

Monitoring

IGF-1, glucose, thyroid function, bone age (children)

—

Duration

Years (children until epiphyseal closure); indefinite (adult GHD)

Not characterised in humans

Standard dose

—

No clinical standard — literature lacks human dosing

Russian practice: often combined with other Khavinson peptides; no FDA/EMA trials.

Animal model dose

—

In vitro: 0.01–10 μg/mL culture medium (mouse thymocytes)

Not translatable to human mg/kg without pharmacokinetic data.

Route

—

Likely SQ or oral (Khavinson school uses both); no published ROA validation

Half-life

—

Not published — dipeptides typically <10 min plasma t½

03Metabolic / Fat Loss Evidence

Parameter

HGH 191AA

Vilon

Primary fat target

Visceral and subcutaneous adipose tissue

—

Mechanism

Lipolysis via hormone-sensitive lipase activation, FFA oxidation

—

Effect on lean mass

Significant lean mass increase (protein synthesis, nitrogen retention)

—

Insulin sensitivity

Acute insulin resistance (anti-insulin effect); chronic neutral-to-improved via fat loss

—

IGF-1 elevation

Dose-dependent, significant — primary anabolic mediator

—

Glucose metabolism

Hyperglycemia risk, especially high doses (AIDS wasting)

—

Body composition

↓ fat mass, ↑ lean mass, ↑ bone mineral density (children)

—

Clinical context

FDA-approved for AIDS wasting (cachexia). Off-label use for body recomposition lacks long-term safety data.

—

04Side Effects & Safety

Parameter

HGH 191AA

Vilon

Injection site reaction

Lipohypertrophy, lipoatrophy, erythema (rotate sites)

—

Fluid retention / Edema

Peripheral edema, arthralgia, carpal tunnel syndrome (dose-dependent)

—

Glucose intolerance

Hyperglycemia, new-onset diabetes (anti-insulin effect)

—

Intracranial hypertension

Benign intracranial hypertension (pseudotumor cerebri) — headache, visual changes, papilledema

—

Slipped capital femoral epiphysis

SCFE risk in children — limp, hip/knee pain (requires surgery)

—

Scoliosis progression

Rapid growth may unmask/progress scoliosis (monitor spine in children)

—

Hypothyroidism

Central hypothyroidism unmasking or worsening (monitor TSH, free T4)

—

Cancer risk

Contraindicated in active malignancy. Theoretical risk in cancer survivors (controversial).

—

Antibody formation

Rare (<2%), typically non-neutralizing. Loss of efficacy if neutralizing antibodies develop.

Not reported; dipeptides generally low immunogenicity

Pancreatitis

Rare. Higher risk in children with certain syndromes (Prader-Willi).

—

Gynecomastia

Adolescent males (physiological during puberty, may be exacerbated)

—

Human safety data

—

Absent from PubMed-indexed literature

Theoretical risk

—

Immune hyperactivation in autoimmune-prone individuals (T-cell differentiation enhancement)

Animal models

—

No adverse effects noted in mouse thymocyte or pineal lymphoid cultures

Absolute Contraindications

HGH 191AA

·Active malignancy or history of cancer (especially childhood cancer survivors with risk factors)
·Acute critical illness (post-cardiac surgery, trauma, acute respiratory failure)
·Diabetic retinopathy (active proliferative or severe non-proliferative)
·Prader-Willi syndrome with severe obesity, sleep apnea, or respiratory impairment
·Closed epiphyses (for growth indications)

Vilon

·Active autoimmune disease (theoretical — no clinical data)

Relative Contraindications

HGH 191AA

·Diabetes mellitus (monitor closely, may require insulin adjustment)
·Intracranial lesions or history of intracranial hypertension
·Scoliosis (monitor curve progression)
·Untreated hypothyroidism (treat before GH initiation)
·Severe obesity (assess OSA risk, cardiovascular status)

Vilon

·Pregnancy / lactation (no safety data)
·Acute infection with cytokine storm risk (immune modulation unknown)

05Administration Protocol

Parameter

HGH 191AA

Vilon

1. Reconstitution (if lyophilized)

Add diluent (sterile water or bacteriostatic water per manufacturer) to vial. Swirl gently — do not shake. Solution should be clear, colorless. Concentration varies by brand (e.g., 5 mg or 10 mg per vial).

No clinical protocols exist in Western peer-reviewed literature. Russian gerontological practice may use 1–10 mg ranges, but dosing is empirical.

2. Injection site

Subcutaneous — rotate sites: abdomen, thigh, buttocks, upper arm. Avoid same site within 1 cm for 2 weeks to prevent lipodystrophy.

Subcutaneous injection (common for Khavinson peptides) or oral (some bioregulators reportedly active orally due to small size). No validated ROA.

3. Timing

Once daily, evening preferred (6–8 PM or pre-sleep). Mimics physiological nocturnal GH secretion. Consistency is critical.

Unknown — no circadian or meal-timing data. Khavinson school often recommends morning administration.

4. Storage

Unreconstituted: refrigerate 2–8 °C, protect from light. Reconstituted: refrigerate, use within 14–28 days (brand-specific). Do not freeze.

Likely lyophilised powder, refrigerated. Reconstitution protocols not published.

5. Needle

27–31G, 4–8 mm insulin syringe or pen device. Pinch skin, 45–90° angle depending on subcutaneous thickness.

—

6. Monitoring

Baseline and periodic: IGF-1 (target age/sex-adjusted midrange), fasting glucose, HbA1c, thyroid function (TSH, free T4), bone age (children), lipid panel. Fundoscopy if headache/visual symptoms.

—

06Stack Synergy

HGH 191AA

+ Ipamorelin

Moderate

View Ipamorelin →

Ipamorelin (GHRP) stimulates endogenous GH release, which is redundant when exogenous rhGH is administered. However, ipamorelin may still amplify pulsatility of remaining endogenous secretion in partial GHD or during GH dose titration. Not typically combined in standard clinical practice; more common in experimental or off-label protocols. Limited evidence for additive benefit.

HGH 191AA: Standard dose per indication
Ipamorelin: 100–200 mcg SQ · morning (if used)
Note: Monitor IGF-1 closely; avoid supraphysiological levels
Primary benefit: Theoretical enhancement of pulsatility; limited clinical rationale

+ Tesamorelin

Weak

View Tesamorelin →

Tesamorelin (GHRH analogue) stimulates endogenous GH secretion, which is unnecessary when exogenous rhGH is already provided. Combining both offers no mechanistic advantage and increases cost, side effects, and IGF-1 elevation risk. Not recommended in clinical practice.

Note: Combination not recommended — choose one GH modality
Primary benefit: None — redundant mechanisms

Vilon

+ Epitalon

Moderate

View Epitalon →

Both are Khavinson bioregulators targeting aging pathways. Epitalon (Ala-Glu-Asp-Gly) acts on telomerase and pineal function; Vilon on immune differentiation and chromatin decondensation. Combined in Russian gerontological protocols for multi-system aging intervention. Lezhava et al. (2023) tested both on aged lymphocyte chromatin, showing distinct epigenetic effects. Complementary, not synergistic in strict pharmacological sense.

Vilon: Empirical — no standard
Epitalon: Empirical — often 10 mg cycles
Frequency: Sequential or concurrent (literature ambiguous)
Primary benefit: Multi-system aging modulation (immune + pineal/circadian)

+ Thymalin

Weak

View Thymalin →

Thymalin is the parent polypeptide complex from which Vilon was isolated. Both target immune differentiation, but Thymalin is a complex mixture (multiple peptides), whereas Vilon is a purified dipeptide. Morozov & Khavinson (1997) described Vilon as a synthetic successor designed to replicate Thymalin's immunomodulatory effects with greater specificity. Redundant in practice; no published combination studies.

Vilon: No standard
Thymalin: 10–100 mg IM (polypeptide complex)
Primary benefit: Redundant — both target T-cell differentiation

Morozov 1997 Khavinson 2020