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Peptide.Guide
EstablishedGLP-1 & IncretinSubQWeekly

Semaglutide

GLP-SM · Ozempic · Wegovy · Rybelsus

Long-acting GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management, with established cardiovascular benefit.

Read dosing protocolJump to references

§ 01   Overview

Overview

Long-acting GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management, with established cardiovascular benefit.

FDA-approved under Ozempic (2017), Wegovy (2021), and Rybelsus (oral). Multiple Phase III trials (STEP, SUSTAIN, SELECT) with tens of thousands of participants.

§ 02   Mechanism

Mechanism of action

Semaglutide is a GLP-1 analog that slows gastric emptying, increases satiety, enhances glucose-dependent insulin secretion, and suppresses glucagon. Its 94% homology with native GLP-1 and albumin binding extend half-life to approximately 7 days, enabling weekly dosing.

  • 01Significant weight loss (10–17% of body weight in STEP trials)
  • 02Improved glycemic control in type 2 diabetes
  • 03Reduced major adverse cardiovascular events (SELECT trial)
  • 04Appetite and food-noise reduction

§ 03   Dosing

Dosing protocol

Standard Protocol

Vial
2 mg or 4 mg typical
BAC Water
2 ml BAC water for 2 mg vial
Dose Range
0.25 – 2.4 mg weekly
Starting Dose
0.25 mg once weekly
Route
SubQ
Timing
Any time of day, consistent weekly
Frequency
Weekly
Cycle
Titrate every 4 weeks: 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg. Long-term use; discontinuation typically causes rebound weight gain.

Storage

Refrigerate 36–46°F. Can be left at room temperature up to 28 days after first use.

§ 04   Evidence

Evidence & research

Established

FDA-approved under Ozempic (2017), Wegovy (2021), and Rybelsus (oral). Multiple Phase III trials (STEP, SUSTAIN, SELECT) with tens of thousands of participants.

FDA Status

FDA-approved (T2D and chronic weight management). Removed from FDA shortage list in early 2025, limiting compounded versions.

§ 05   Stacks

Common stacks

Tirzepatide

Alternative for stalls

Cagrilintide

Amylin co-agonist, appetite

BPC-157

GI tolerability

§ 06   News

In the news

8 articles from the last 12 months · updates hourly

§ 07   Sourcing

Sourcing & supply

Regulatory status

FDA-approved

This compound has an FDA approval for at least one indication. Brand pharmacy channels exist. Compounding may or may not be available depending on shortage status.

503B pharmacies · 4

503B pharmacy

Empower Pharmacy

Rx required

One of the largest US compounders by volume; dual 503A + 503B. Repeat FDA enforcement history and ongoing Lilly litigation.

FDA 503B Registered6 flags on record
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503B pharmacy

Olympia Pharmaceuticals

Rx required

35+ year family-owned dual 503A/503B licensed in 48–49 states. Among the cleanest mid-sized 503Bs operating today.

FDA 503B Registered3 flags on record
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503B pharmacy

Strive Pharmacy

Rx required

503A, licensed in all 50 states. Triple-credentialed (PCAB + NABP + LegitScript). Partner of Lavender Sky.

PCAB Accredited +21 flag on record
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503B pharmacy

ProRx

Rx required

FDA-registered 503B. Major semaglutide/tirzepatide recall in August 2024 over sterility concerns.

FDA 503B Registered1 flag on record

Telehealth (Rx) · 11

Telehealth

Defy Medical

Rx required

Broadest peptide formulary in legitimate US telehealth. 13-year history, concierge cash-pay, no known lawsuits.

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Telehealth

Ro

Rx required

Only major telehealth that avoided lawsuits by signing direct partnerships with LillyDirect and NovoCare.

LegitScript Certified
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Telehealth

Hims & Hers

Rx required

All 50 states. Owns its own FDA-registered compounding facility. Under FDA scrutiny.

LegitScript Certified2 flags on record
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Telehealth

Henry Meds

Rx required

Asynchronous budget GLP-1 platform. Named in Lilly litigation; pharmacy partner has federal plea history.

LegitScript Certified2 flags on record
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Telehealth

Mochi Health

Rx required

Central defendant in Lilly v. Mochi: bellwether case on telehealth-pharmacy vertical integration.

1 flag on record
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Telehealth

Marek Health

Rx required

Premium hormone optimization. All 50 states. 4.8 Trustpilot. Partners include Hallandale.

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Telehealth

Ivim Health

Rx required

~100 providers. Filed amicus brief supporting OFA's tirzepatide appeal. Joined Outsourcing Facilities Association.

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Telehealth

Maximus Tribe

Rx required

Performance medicine platform. Flagship 'Oral TRT+' (enclomiphene + pregnenolone). Claims LegitScript-certified pharmacy partners.

1 flag on record
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Telehealth

Blokes / Joi Women's Wellness

Rx required

Men's + women's optimization platform. TRT in 34 states. 4.6–4.8 Trustpilot.

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Telehealth

Fountain TRT / Fountain Vitality

Rx required

Urologist-led TRT + GLP-1 platform. 4-star Trustpilot. Distinct from Fountain Life.

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Telehealth

Superpower

Rx required

Longevity-biomarker subscription ($199/yr, 100+ biomarkers) with narrow prescription formulary.

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International · 1

International

Trident Peptides

1,299+ Trustpilot reviews (5-star). Strongest review base in UK research peptides. No visible ISO/GMP; COAs not posted.

1 flag on record
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Research-use-only · 6

Research-use-only

Limitless Life Nootropics

'Only BBB-accredited peptide company' (since 2020). Claims three-lab third-party testing. Broad catalog.

BBB Accredited +1
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Research-use-only

Core Peptides

Broad catalog, widest payment range. Mid-credibility: Knoji 2.5/5 and one scam-impersonation report.

Third-Party Testing1 flag on record
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Research-use-only

Elite Research USA

High-risk. Finnrick tested 47 samples across 7 products → ratings B to E. Heavy TikTok marketing. No accreditations verified.

2 flags on record
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Research-use-only

Prime Peptides

Uses Janoshik testing. FDA warning letter December 2024 for GLP-1s.

Janoshik Testing1 flag on record
Research-use-only

Xcel Peptides

Still operating despite FDA warning letter.

1 flag on record
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Research-use-only

Summit Research

FDA warning letter December 2024 across multiple GLP-1s.

1 flag on record

Listings are informational, not endorsement. Verify credentials and flags against FDA and PCAB databases before purchasing. Full directory & how to verify →

§ 09   Safety

Safety & side effects

Side effects

  • 01Nausea (most common, dose-dependent)
  • 02Constipation or diarrhea
  • 03Delayed gastric emptying
  • 04Fatigue during titration
  • 05Rare: gallbladder issues, pancreatitis

Contraindications

  • 01Personal/family history of medullary thyroid carcinoma
  • 02Multiple Endocrine Neoplasia type 2
  • 03Active pancreatitis
  • 04Pregnancy

§ 10   References

Selected references

  1. 01

    STEP 1 — weight management

    NEJM 2021

  2. 02

    SELECT — cardiovascular outcomes

    NEJM 2023

  3. 03

    SUSTAIN — T2D

    Lancet 2017

◆   In this categoryMore from GLP-1 & Incretin
01

Tirzepatide

Dual GIP/GLP-1 receptor agonist producing greater average weight loss than semaglutide in head-to-head trials.

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03

Cagrilintide

Long-acting amylin analog that slows gastric emptying and enhances satiety, typically paired with semaglutide (CagriSema).

Clinical
04

BPC-157

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05

Mazdutide

Dual GLP-1 / glucagon receptor agonist showing strong weight loss and metabolic effects in late-stage trials, particularly in Asian populations.

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This site is for educational and research purposes only. It does not constitute medical advice. Always consult a qualified healthcare provider before using any peptide or supplement.