Side-by-side · Research reference
IpamorelinvsSemaglutide
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
APhase 1Reviewed21/57 cited
BFDA-ApprovedVerified15/53 cited
Ipamorelin
Selective GHRP · Ghrelin Mimetic
SQ · Multiple sites · 1–3×/day
Semaglutide
GLP-1 RA · FDA-Approved
SQ · Abdomen / thigh / arm · Once weekly
01Mechanism of Action
Parameter
Ipamorelin
Semaglutide
Primary target
Ghrelin receptor (GHS-R1a) on anterior pituitaryRaun 1998
GLP-1 receptor (GLP-1R)WEGOVY (semaglutide) injection 2021
Pathway
GHS-R1a binding → Gαq/11 → ↑intracellular Ca²⁺ → GH vesicle exocytosisRaun 1998Bowers 1991
GLP-1R agonism → ↑glucose-dependent insulin secretion, ↓glucagon, ↓gastric emptying, ↓appetite via hypothalamic centresWilding 2021
Downstream effect
GH pulse amplification, IGF-1 elevation, recovery and lipolytic effectsBowers 2002
Improved glycemic control, reduced caloric intake, body-weight reduction, cardiovascular risk reductionWilding 2021
Feedback intact?
Yes — pulsatile pattern preserved; somatostatin feedback activeBowers 2002
Glucose-dependent insulin release preserves physiological feedback
Origin
Pentapeptide H-Aib-His-D-2-Nal-D-Phe-Lys-NH₂; rationally designed for ghrelin-receptor selectivityRaun 1998
Modified GLP-1(7-37) with two amino-acid substitutions and C-18 fatty-acid acylation for albumin binding and 168-h half-lifeWEGOVY (semaglutide) injection 2021
Antibody development
Not reported in short-term studies
—
02Dosage Protocols
Parameter
Ipamorelin
Semaglutide
Standard dose
200–300 mcg per injectionRaun 1998
Anecdotal community range; clinical doses 1–3 mg IV in trials.
—
Frequency
1–3× per day
Once daily pre-sleep is most common; twice or thrice for advanced users.
Once weekly, same day each week
Lower / starter dose
100 mcg per dose
—
Evidence basis
Phase 1 + clinical practiceRaun 1998Sigalos 2018
FDA-approved · Phase 3 RCTsWilding 2021WEGOVY (semaglutide) injection 2021
Duration
8–12 weeks on / 4 weeks off (anecdotal)
GHS-R desensitisation reported with continuous dosing.
Indefinite for chronic indication
Discontinuation results in weight regain.
Reconstitution
Bacteriostatic water; typical 2 mL per 5 mg vial
Pre-mixed pen device (commercial). Research lyophilised vial: bacteriostatic water per label.
Timing
Pre-sleep + fasted preferred; 30 min away from food
Any time of day, with or without food
Half-life
~2 hoursRaun 1998
Longer than GHRP-6 (15 min); shorter than CJC-1295-DAC (~8 days).
~7 days (168 h)WEGOVY (semaglutide) injection 2021
Standard dose (weight, Wegovy)
—
2.4 mg / week (after 16-wk titration)WEGOVY (semaglutide) injection 2021Wilding 2021
Titration schedule
—
0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg over 16 weeks
Mitigates GI side effects.
04Side Effects & Safety
Parameter
Ipamorelin
Semaglutide
Hunger
Mild appetite increase via ghrelin-receptor crosstalk
—
Injection site reaction
Mild irritation possible
Mild erythema, pruritus
GH excess (overdose)
Joint pain, edema, insulin resistance
—
IGF-1 elevation
Dose-dependent; monitor with chronic high-dose use
—
Cancer risk
Theoretical via GH/IGF-1 axis; contraindicated in active malignancy
—
Thyroid C-cell tumours
—
Boxed warning — contraindicated in MEN2 / personal or family MTC historyWEGOVY (semaglutide) injection 2021
Hypoglycemia
—
Low risk as monotherapy; elevated when combined with sulfonylureas / insulin
Gallbladder events
—
Increased cholelithiasis
Heart rate
—
Modest ↑ resting HR (~2-4 bpm)
Absolute Contraindications
Ipamorelin
- ·Active malignancy or cancer history
- ·Pregnancy / breastfeeding
- ·Disrupted hypothalamic-pituitary axis
Semaglutide
- ·Personal or family history of medullary thyroid carcinoma
- ·Multiple endocrine neoplasia syndrome type 2
- ·Pregnancy / breastfeeding
- ·Hypersensitivity to semaglutide
Relative Contraindications
Ipamorelin
- ·Untreated diabetes
- ·Severe insulin resistance
- ·Concurrent corticosteroid use (theoretical desensitisation)
Semaglutide
- ·Severe gastroparesis
- ·History of pancreatitis
- ·Diabetic retinopathy (may worsen with rapid glycemic improvement)
05Administration Protocol
Parameter
Ipamorelin
Semaglutide
1. Reconstitution
Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL. Roll gently. Solution should be clear.
Commercial: pre-filled pen, no reconstitution. Research vial: per-label or bacteriostatic water.
2. Injection site
Subcutaneous, abdomen or thigh. Rotate sites. Pinch fat for shallow SQ delivery.
SQ — abdomen, thigh, or upper arm. Rotate sites weekly to avoid lipohypertrophy.
3. Timing
Pre-sleep optimal — aligns with natural GH pulse. Some protocols add a morning fasted dose.
Once weekly, same day. Day can be changed if ≥2 days separate doses.
4. Storage
Lyophilised: room temp, protected from light. Reconstituted: refrigerate 2–8 °C, use within 30 days.
Pen: refrigerate 2–8 °C unopened; room temp ≤30 °C up to 56 days after first use.
5. Needle
29–31G, 4–8 mm insulin syringe.
Pen-supplied 31–34G needle. Research vial: 27–31G insulin syringe.
06Stack Synergy
Ipamorelin
+ Tesamorelin
StrongIpamorelin (GHRP) + tesamorelin (GHRH analogue) is the textbook dual-axis GH stack. They activate two distinct pituitary receptors — the ghrelin receptor and the GHRH receptor — producing a synergistic GH pulse larger than either alone. Ipamorelin's selectivity (no cortisol/prolactin spike) makes it the ideal GHRP partner for long-term protocols.
- Ipamorelin
- 200–300 mcg SQ · pre-sleep
- Tesamorelin
- 2 mg SQ · same injection · pre-sleep
- Primary benefit
- Maximal GH pulsatility, fat loss, recovery, sleep depth
+ CJC-1295 (no DAC)
StrongCJC-1295 (no DAC) is a short-acting GHRH analogue. Combined with ipamorelin (GHRP), the pulse is amplified across both receptor systems with timing similar to native physiology. Without the DAC modification, the stack maintains sharp peaks rather than the sustained elevation seen with CJC-1295-DAC + ipamorelin.
- Ipamorelin
- 200–300 mcg SQ · pre-sleep
- CJC-1295 (no DAC)
- 100 mcg SQ · same injection
- Primary benefit
- Pulsatile GH stimulation matching physiological pattern
Semaglutide
+ Tirzepatide
WeakCombining two GLP-1 RA-class drugs is not clinically validated and risks additive GI toxicity. Tirzepatide's GIP component already provides complementary mechanism vs pure GLP-1; stacking with semaglutide adds receptor saturation but no synergy. NOT recommended.
- Note
- Stack not recommended — choose one GLP-1 RA
- Primary benefit
- (none — additive toxicity, no synergy)