Side-by-side · Research reference

IGF-DESvsRetatrutide

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

AAnimal-StrongHUMAN-REVIEWED8/60 cited

BPhase 2HUMAN-REVIEWED10/41 cited

IGF-DES

IGF-1 Analogue · Truncated N-Terminal

~10×Potency vs IGF-1

ReducedIGFBP binding

ResearchStatus

Injection (local or systemic) · Research protocols onlyBredehöft 2008

Retatrutide

Triple-receptor agonist · Phase 3

1–12 mgWeekly doseJastreboff 2023

24.2%Body-weight ↓Jastreboff 2023

~6 daysHalf-life (est)

SQ · Abdomen · Once weekly

01Mechanism of Action

Parameter

IGF-DES

Retatrutide

Primary target

IGF-1 receptor (IGF1R)Shields 2007

GLP-1R + GIPR + Glucagon receptor (triple agonism)Jastreboff 2023

Pathway

IGF1R activation → PI3K/Akt & MAPK signaling → protein synthesis, proliferation

Triple-receptor activation → ↑insulin (GLP-1+GIP), ↓gastric emptying, ↑lipid handling, ↑energy expenditure (glucagon component)Jastreboff 2023

Downstream effect

Enhanced muscle protein synthesis, myoblast differentiation, reduced apoptosis, cell proliferation

Maximal weight loss across class. Glucagon component drives lipolysis and energy expenditure beyond GLP-1+GIP aloneJastreboff 2023

Feedback intact?

Unknown — no human endocrine feedback data

—

Origin

Synthetic truncation of native IGF-1 — removal of N-terminal Gly-Pro-Glu tripeptideBredehöft 2008

Synthetic peptide engineered for balanced affinity at three incretin / glucagon receptorsJastreboff 2023

Antibody development

—

02Dosage Protocols

Parameter

IGF-DES

Retatrutide

Research dose range

10–100 ng/mL (in vitro); μg doses (animal models)

Highly context-dependent; no standardized human protocol.

—

Route

Subcutaneous or intramuscular (local injection favored)

Local delivery maximizes tissue-specific uptake.

—

Frequency

Variable — daily to multiple times daily in research

Once weekly

Evidence basis

Animal models + in vitro only

Phase 2 trial; Phase 3 ongoingJastreboff 2023

Human data

None — no clinical trials

—

Half-life

Shorter than IGF-1 due to reduced IGFBP binding

Rapid tissue uptake, limited systemic circulation.

~6 days (estimated from class)

Standard dose

—

12 mg / week (max efficacy)Jastreboff 2023

Phase 2 trial dose. Phase 3 dosing TBD.

Titration schedule

—

2 mg → 4 mg → 8 mg → 12 mg over 16 weeks

Duration

—

Indefinite for chronic indication (presumed)

Reconstitution

—

Investigational; not commercially available

Timing

—

Any time of day

03Metabolic / Fat Loss Evidence

Parameter

IGF-DES

Retatrutide

Primary mechanism

Indirect via muscle hypertrophy → metabolic rate elevation

—

Direct lipolysis

Minimal evidence — IGF-1 axis primarily anabolic, not lipolytic

—

Prostate model

Inhibited BPH cell proliferation when combined with vitamin D3 analogueCrescioli 2002

Context-specific anti-proliferative effect, not fat loss.

—

04Side Effects & Safety

Parameter

IGF-DES

Retatrutide

Hypoglycemia risk

Theoretical — IGF-1 axis enhances glucose uptake

—

Mitogenic risk

Chronic IGF-1 receptor activation may promote cell proliferation, potential tumor growthCrescioli 2002

—

Injection site reaction

Expected — erythema, irritation, local swelling

—

Edema / Fluid retention

Possible via sodium retention (IGF-1 axis effect)

—

Human safety data

Absent — no human trials, all effects theoretical or extrapolated

—

Unknown long-term effects

No chronic dosing studies in humans; endocrine, metabolic consequences unknown

—

GI symptoms

—

Nausea, vomiting, diarrhea (very common, dose-dependent)Jastreboff 2023

Heart rate

—

↑ resting HR (3–7 bpm at 12 mg)Jastreboff 2023

Glucose handling

—

Glycemic improvement; rare hyperglycemia from glucagon component

Pancreatitis risk

—

Class warning

Thyroid C-cell tumours

—

Class warning (presumed)

Pregnancy / OB

—

Avoid (insufficient data)

Absolute Contraindications

IGF-DES

·Active malignancy or history of cancer (mitogenic risk)
·Pregnancy / lactation (no safety data)
·Hypoglycemia disorders

Retatrutide

·MTC personal or family history (presumed class effect)
·Pregnancy / breastfeeding

Relative Contraindications

IGF-DES

·Diabetes mellitus (unpredictable glucose effects)
·Renal or hepatic impairment (clearance unknown)
·Edema-prone conditions (heart failure, nephrotic syndrome)

Retatrutide

·Severe gastroparesis
·History of pancreatitis
·Severe cardiovascular disease (HR signal)

05Administration Protocol

Parameter

IGF-DES

Retatrutide

1. Research context only

Des(1-3)IGF-1 has no approved human protocol. All administration details are derived from animal or in vitro research and should not be construed as medical guidance.

Investigational peptide. Research vials reconstituted with bacteriostatic water per label.

2. Reconstitution (if lyophilized)

Sterile water or bacteriostatic water per research protocol. Gently swirl; do not shake. Store reconstituted peptide at 2–8 °C.

SQ — abdomen, thigh, or upper arm. Rotate weekly.

3. Injection site

Subcutaneous (abdomen, thigh) or intramuscular (deltoid, vastus lateralis). Local injection to target tissue (e.g., muscle group) may enhance regional uptake.

Once weekly, same day.

4. Timing

Frequency and timing vary by research design. Post-exercise or fasted state may theoretically enhance muscle uptake.

Refrigerate 2–8 °C. Light-protected.

5. Needle gauge

27–31G insulin syringe for subcutaneous; 25–27G for intramuscular.

27–31G, 4–8 mm insulin syringe.

6. Monitoring

Glucose monitoring essential (hypoglycemia risk). No established IGF-1 or safety labs for human use.

—

06Stack Synergy

IGF-DES

+ BPC-157

Moderate

View BPC-157 →

Des(1-3)IGF-1 promotes myoblast differentiation and protein synthesis, while BPC-157 enhances tissue repair, angiogenesis, and collagen synthesis. Both act on distinct pathways (IGF1R vs gastric pentadecapeptide mechanisms) to support muscle recovery and connective tissue integrity. Synergy is mechanistic but lacks direct co-administration studies.

Des(1-3)IGF-1: Research dose post-workout (local IM)
BPC-157: 250–500 mcg SQ, daily or twice daily
Frequency: Daily or per research protocol
Primary benefit: Accelerated muscle repair, enhanced hypertrophy, connective tissue support

+ TB-500

Moderate

View TB-500 →

TB-500 (Thymosin Beta-4 fragment) promotes cell migration, angiogenesis, and wound healing via actin regulation. Des(1-3)IGF-1 drives protein synthesis and myoblast proliferation. Combined, these peptides may synergistically enhance muscle recovery, repair, and hypertrophy through complementary anabolic and regenerative pathways. No direct human co-administration data.

Des(1-3)IGF-1: Research dose post-workout (local IM)
TB-500: 2–5 mg SQ, 2× weekly
Frequency: Per research cycle
Primary benefit: Muscle hypertrophy, injury recovery, vascular support

Retatrutide

— no documented stacks