Retatrutide Dosage Guide for Canadian Researchers

Retatrutide (development code LY3437943) is a triple agonist peptide targeting GLP-1, GIP, and glucagon receptors simultaneously. It has generated significant interest in the research community following Phase 2 clinical trial data published in the New England Journal of Medicine in 2023, which reported substantial body weight reduction in study participants over 48 weeks.

This guide is a research reference for Canadian laboratories and scientists working with Retatrutide.

Retatrutide is a once-weekly injectable peptide developed by Eli Lilly. Unlike semaglutide (GLP-1 only) or tirzepatide (GLP-1 + GIP), Retatrutide adds glucagon receptor agonism as a third mechanism — making it a "triple agonist."

The three receptor targets work synergistically:

• GLP-1 receptor agonism — reduces appetite, slows gastric emptying, improves insulin sensitivity
• GIP receptor agonism — enhances insulin secretion, may improve fat metabolism
• Glucagon receptor agonism — increases energy expenditure, promotes fat oxidation

This combination produced the highest weight reduction percentages observed in any peptide clinical trial to date at the time of publication.

Peptide-Labs.ca offers Retatrutide in three vial sizes to accommodate different research protocols:

All vials are lyophilized powder requiring reconstitution with bacteriostatic water before use.

Retatrutide reconstitution follows the same principles as other lyophilized peptides:

For a 10mg vial:

• Add 1mL BAC water → 10,000 mcg/mL concentration
• Add 2mL BAC water → 5,000 mcg/mL concentration

For a 30mg vial:

• Add 2mL BAC water → 15,000 mcg/mL concentration
• Add 3mL BAC water → 10,000 mcg/mL concentration

Always inject BAC water slowly against the glass wall of the vial — never directly onto the powder. Swirl gently to dissolve; do not shake.

Use the Peptide-Labs.ca Reconstitution Calculator to calculate exact draw volumes for any dose and concentration.

The Phase 2 NEJM trial used escalating weekly doses administered subcutaneously. The dose escalation schedule used in the trial was:

• Weeks 1–4: 2mg/week
• Weeks 5–8: 4mg/week
• Weeks 9–12: 8mg/week
• Weeks 13–24: 12mg/week (or 4mg/8mg maintenance arms)

The highest dose cohort (12mg/week) produced a mean weight reduction of approximately 24% at 48 weeks in the trial population.

Note: This data is provided for research reference only. Peptide-Labs.ca products are for in vitro and laboratory use only.

Using a 30mg vial reconstituted with 2mL BAC water (15,000 mcg/mL = 15 mg/mL):

For a 2mg (2,000 mcg) dose:

• 2,000 ÷ 15,000 = 0.133 mL (approximately 13 units on a 100-unit insulin syringe)

For a 4mg (4,000 mcg) dose:

• 4,000 ÷ 15,000 = 0.267 mL (approximately 27 units)

For an 8mg (8,000 mcg) dose:

• 8,000 ÷ 15,000 = 0.533 mL (approximately 53 units)

The Peptide-Labs.ca Calculator handles all of this automatically — select Retatrutide from the dropdown, enter your vial size and BAC water volume, and it calculates draw volumes for each dose preset.

• Lyophilized (unreconstituted): Store at -20°C; stable for 12–24 months
• Reconstituted: Refrigerate at 2–8°C; use within 4–6 weeks
• Protect from light at all stages
• Do not freeze reconstituted solution

Peptide-Labs.ca is a Canadian supplier offering Retatrutide 10mg, 20mg, and 30mg vials with third-party COA verification — view the COA page for current batch results (Lab ID: RET-088, 99.46% purity). View the Retatrutide product page or see all available research peptides.

We ship to researchers across Canada, including Edmonton, Alberta, and all other provinces. See our Canadian peptide shipping guide for delivery details.

For reconstitution, you'll need bacteriostatic water — we stock BAC Water 3mL and BAC Water 10mL.

• How to Reconstitute BPC-157 — step-by-step reconstitution guide applicable to all peptides
• CJC-1295 + Ipamorelin Stack Guide — another popular research peptide combination
• How to Buy Research Peptides in Canada — supplier selection checklist for Canadian researchers

All products sold by Peptide-Labs.ca are intended exclusively for in vitro research and laboratory use. Not for human or veterinary use.