Why Microdosing a GLP-1 Is Better

We are just scratching the surface of what Retatrutide will do to revolutionize fat loss in the coming years.

Early data shows it is vastly superior to Semaglutide and Tirzepatide.

Hopefully, by the time Reta is approved by the FDA, microdosing will be the standard practice for administration.

Traditionally, all GLPs are administered as a once-weekly injection, but many users now opt for an alternative approach: microdosing—splitting the total weekly dose into 3-4 smaller injections every other day.

Why?

This method leads to more stable concentration levels, reduces side effects, and enhances efficacy.

Today, I will explain precisely why microdosing is much more effective than the once-per-week injection method.

GLP-1 Half-Life Explained

Retatrutide has a half-life of approximately 6-7 days, meaning that 50% of the drug remains active in the body one week after administration.

This extended half-life is why pharmaceutical guidelines suggest a single weekly injection (and it usually leads to greater patient compliance).

However, despite this long duration, how the body absorbs, distributes, and responds to a drug can vary significantly depending on the dosing schedule.

How Half-Life Affects Drug Metabolism

• After 1 half-life (~7 days): 50% of the drug remains.

• After 2 half-lives (~14 days): 25% remains.

• After 3 half-lives (~21 days): 12.5% remains.

While this slow clearance means that retatrutide has a sustained effect, it also means that a large single dose results in high peaks followed by a prolonged decline, leading to inconsistent effects.

The Downside of Once-Weekly Injections

While once-weekly dosing is convenient, it has several major drawbacks:

1. Sharp Peaks and Sudden Drops

• Large doses create high drug peaks shortly after injection, leading to strong but short-lived effects.

• The concentration then declines steadily, often leading to a loss of appetite suppression and glucose control toward the end of the week.

2. Increased Side Effects from High Peaks

• Gastrointestinal issues (nausea, vomiting, bloating) are more pronounced when drug levels spike.

• Some users report extreme fatigue, malaise, and dizziness for the first 48 hours post-injection.

3. Inconsistent Fat Loss and Blood Sugar Regulation

• High peaks can suppress appetite too much, leading to under-eating early in the week and rebound hunger later.

• Glucose control becomes more variable, increasing the risk of blood sugar swings.

4. Nervous System Overload

• Many users report higher resting heart rates, lower HRV, and disrupted sleep in the first few days after a large injection (HINT: add in 2-3 grams daily of taurine if you are experiencing these issues).

• This nervous system stress can impact recovery, performance, and overall well-being.

The graph below illustrates the fluctuations in GLP-1 receptor concentration with once-weekly retatrutide injections.

Notice the large spikes followed by steep drops, leading to inconsistent blood concentration levels of the peptide throughout the week.

Why Microdosing Retatrutide is Superior

Microdosing involves dividing the total weekly dose into 3-4 smaller injections every other day (EOD). This provides a smoother response profile, reducing negative side effects and amplifying benefits.

How Microdosing Works

• Instead of a single 2mg injection once per week, take 0.5mg every other day (Monday, Wednesday, Friday, and Sunday).

• This results in more consistent blood levels without the harsh peaks and crashes.

The Benefits of Microdosing

1. Steady Drug Levels → Better Tolerability

• Prevents sudden spikes and prolonged crashes, keeping blood concentrations in a stable range.

• Reduces nausea, dizziness, and fatigue associated with high peak concentrations.

2. Reduced Gastrointestinal Side Effects

• Smaller doses prevent excessive gut motility suppression, minimizing nausea, bloating, and constipation.

3. Enhanced Fat Loss While Preserving Lean Mass

• A more consistent blood level optimizes fat oxidation and muscle retention.

• Large swings in concentration can disrupt metabolic efficiency, making microdosing a better approach for those looking to maintain lean mass.

4. Improved Appetite Control

• Microdosing prevents excessive appetite suppression early in the week, and hunger rebounds before the next injection.

• It helps users maintain a steady caloric intake, improving long-term fat loss results.

5. More Effective Glucose and Insulin Regulation

• Blood sugar control remains more stable throughout the week, reducing fluctuations in insulin levels.

• Prevents sudden energy crashes and cravings linked to glucose instability.

6. Less Nervous System Stress

• Users report less strain on HRV, better sleep, and improved recovery with microdosing.

• This even peptide exposure prevents the overstimulation of adrenergic (fight-or-flight) responses.

The graph below illustrates the stabilized GLP-1 receptor concentration levels achieved with microdosing.

In contrast to the once-weekly graph, notice how peptide levels remain stable with only minor fluctuations, preventing the extreme highs and lows seen in once-weekly dosing.

Microdosing for Maximum Benefit

While once-weekly injections may be convenient, microdosing retatrutide every other day offers a superior approach for optimizing metabolic health, minimizing side effects, and sustaining fat loss.

In summary, here’s why we microdose:

✅ Prevents large peaks and crashes 

✅ Reduces nausea, fatigue, and other side effects 

✅ Optimizes fat loss while preserving muscle 

✅ Enhances appetite control and glucose regulation 

✅ Improves nervous system balance and recovery

For those serious about maximizing the benefits of retatrutide, switching to an every-other-day protocol may be the best move.

How to Implement Microdosing In Your Research

To transition from once-weekly injections to microdosing:

• Divide your total weekly dose into 3-4 equal injections.

• Example: If researching with 2mg per week, take 0.5mg every other day.

• Maintain a consistent schedule to keep blood levels steady.

Best,

Hunter

P.S. We extended the retatrutide sale until midnight PST tonight at BioLongevity Labs.

• When you spend $500 or more on Retatrutide, you can get 20% off your purchase now through tonight at Midnight PST!

• Spend $2500 or more at BioLongevity Labs before tonight at Midnight PST, and you’ll receive FREE ACCESS to the Peptide Stacking Masterclass on Thursday, Feb 6th at 6 PM EST with Jay Campbell and me.

Use code HUNTER10 for 10% off.

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