Ipamorelin vs Semaglutide: Side-by-Side Comparison
A comprehensive comparison of Ipamorelin and Semaglutide: mechanism, dosage, approval status, clinical results, side effects, and which is right for your goals.
Ipamorelin
AKA: NNC 26-0161
A selective growth hormone secretagogue that boosts GH release with minimal side effects — popular for anti-aging and body composition.
Investigational / ResearchSemaglutide
AKA: Ozempic, Wegovy, Rybelsus
The peptide that started the weight loss revolution — FDA-approved, clinically proven, and widely accessible.
FDA ApprovedHead-to-Head Comparison
| Category | Ipamorelin | Semaglutide |
|---|---|---|
| Class | Growth Hormone Secretagogue (GHRP) | GLP-1 Receptor Agonist |
| Typical Dose | 200-300 mcg 1–3 times daily (often before bed and/or around workouts) | 1.7-2.4 mg Once weekly (injectable); once daily (Rybelsus oral) |
| Half-Life | ~2 hours | ~7 days |
| Administration | Subcutaneous injection | Subcutaneous injection (abdomen, thigh, upper arm), Oral tablet (Rybelsus) |
| FDA Approval | No FDA approval. Research use only. | FDA approved for T2D (Ozempic, 2017), obesity (Wegovy, 2021), CV risk reduction (2023), oral T2D (Rybelsus, 2019)✓ Edge |
| Primary Uses | Growth hormone stimulation, Body composition improvement, Anti-aging, Sleep quality enhancement, Recovery optimization | Type 2 diabetes (Ozempic), Weight loss/obesity (Wegovy), Cardiovascular risk reduction (SELECT trial) |
| Legal Status | Research chemical in the US. Not FDA approved. Available through peptide research suppliers. | FDA approved. Requires prescription. Widely available through physicians and telehealth. |
Clinical Trial Outcomes: What the Data Shows
The following data comes from Phase 2/3 trials. These trials used different populations, durations, and endpoints — direct comparison is directional, not definitive.
| Metric | Ipamorelin | Semaglutide |
|---|---|---|
| Drug class | Growth Hormone Secretagogue (GHRP) | GLP-1 Receptor Agonist |
| Peak weight loss (mean, max dose) | See trial data | 14.9% (68 weeks) |
| Trial population | See published trials | N=1961, STEP 1 |
| FDA approval (obesity) | Not approved — investigational | Approved |
| Thermogenesis mechanism | Minimal | Minimal |
Side Effects Comparison
Ipamorelin
Semaglutide
Who Should Choose Which?
Choose Ipamorelin if:
- • You want growth hormone stimulation
- • You are comfortable with investigational compounds and clinical trial enrollment
- • Subcutaneous injection is your preferred route
- • You are willing to wait for FDA approval (projected 2027–2028) or can enroll in an active trial
Choose Semaglutide if:
- • You want type 2 diabetes (ozempic)
- • You want an FDA-approved option available by prescription today
- • Subcutaneous injection (abdomen, thigh, upper arm) is your preferred route
- • You need immediate access — pharmacy-dispensed, insurance-eligible, telehealth available
Switching From One to the Other
If you are currently on Semaglutide and considering switching to Ipamorelin (or vice versa), here is what to plan for:
Switching from Semaglutide to Ipamorelin
- • Eligibility: Ipamorelin is only available in clinical trials. Standard prescription switching is not yet possible.
- • Washout: Weekly GLP-1 drugs typically require 4–8 weeks washout due to extended half-lives (~7 days). Overlapping two GLP-class drugs increases GI side effect risk.
- • Re-titration: Start at the lowest dose of the new drug and re-titrate — even if you tolerated high doses of the previous drug.
- • Expect adjustment: 4–12 weeks for full receptor adaptation to the new molecule.
Switching from Ipamorelin to Semaglutide
- • Access: Semaglutide is FDA approved and available by prescription.
- • Washout: Same 4–8 week washout principle applies — allow the first drug to clear before starting the second.
- • Weight: Expect some weight regain during the washout period as appetite normalizes without active drug coverage.
- • Indication: Ensure Semaglutide is appropriate for your indication — approval status and coverage differ.
Frequently Asked Questions
What is the main difference between Ipamorelin and Semaglutide?
Ipamorelin (Growth Hormone Secretagogue (GHRP)) and Semaglutide (GLP-1 Receptor Agonist) differ in their receptor targets, mechanism of action, and clinical applications. Ipamorelin: A selective growth hormone secretagogue that boosts GH release with minimal side effects — popular for anti-aging and body composition. Semaglutide: The peptide that started the weight loss revolution — FDA-approved, clinically proven, and widely accessible.
Which is better for weight loss — Ipamorelin or Semaglutide?
Both Ipamorelin and Semaglutide may support weight loss, but their approved indications and clinical evidence differ. Ipamorelin approval: No FDA approval. Research use only.. Semaglutide approval: FDA approved for T2D (Ozempic, 2017), obesity (Wegovy, 2021), CV risk reduction (2023), oral T2D (Rybelsus, 2019). Consult a healthcare provider to determine which is appropriate for your situation.
Can you take Ipamorelin and Semaglutide together?
Combining Ipamorelin and Semaglutide has not been studied in clinical trials and is not recommended without direct medical supervision. The pharmacological overlap between them may increase the risk of side effects.
Is Ipamorelin stronger than Semaglutide?
Ipamorelin and Semaglutide have different mechanisms and have not been directly compared in head-to-head trials. The available trial data for each drug was generated in different populations and timeframes, making direct comparison difficult.
Which should I choose — Ipamorelin or Semaglutide?
Semaglutide is FDA approved and available by prescription today. Ipamorelin remains investigational and is only accessible through clinical trials. Most patients will choose Semaglutide until Ipamorelin receives FDA approval, projected for 2027–2028.
Can I switch from Semaglutide to Ipamorelin?
Switching between GLP-class drugs is possible but requires a washout period and physician oversight. For weekly injectable GLP-1 drugs, a typical washout is 4–8 weeks due to the extended half-life. Switching while Ipamorelin remains investigational is not a standard clinical option — you would need to enroll in a clinical trial or wait for FDA approval. Discuss transition planning with your prescribing physician.