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    GLP-1 Dosing Stability Calculator

    Model how GLP-1 drug levels change with different weekly doses and injection frequencies so you can have a safer conversation with your clinician.

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    Select Compound
    Weekly Target Dose
    Injection Frequency

    Dosing

    EVERY 3 DAYS

    Dose per Injection

    0.40 mg

    Rounded for practical measurement

    Injections per Week

    2.3

    Exact mathematical split:0.429 mg
    Actual weekly total:0.93 mg
    Weekly variance:-0.07 mg vs target

    Blood Plasma Stability

    GOOD

    Avg Plasma Level

    1.33 mg

    Lower indicates more stable blood levels and less side effects

    Peak / Trough Ratio

    26%

    Min plasma level:1.16 mg
    Max plasma level:1.46 mg
    Variance:0.30 mg
    FrequencyDose / InjectionWeekly DeliveredPlasma StabilityInjections/Week
    Every Other Day (q2d)
    		0.30 mg
    1.05 mg
    +0.05 mg vs target
    Excellent stability
    3.5x
    Every 3 Days (q3d)
    		0.40 mg
    0.93 mg
    -0.07 mg vs target
    Moderate stability
    2.3x
    Twice Weekly
    		0.50 mg
    1.00 mg
    Matches target
    Moderate stability
    2.0x
    Weekly
    		1.00 mg
    1.00 mg
    Matches target
    High variation
    1.0x

    Calculations assume steady-state pharmacokinetics with volume of distribution (Vd) ≈ 1 L. Lower peak/trough percentages indicate smoother plasma concentrations. Doses are rounded to 0.1 mg for practical administration.

    FrequencyBest ForTrade-offs
    Once Weekly (Standard)Most users; proven protocol from clinical trialsHigher peak may cause more nausea; simpler schedule
    Twice WeeklyUsers with GI sensitivity; those wanting steadier appetite controlLower peaks reduce nausea; more injections; off-label
    Every 3 Days (Q3D)Tirzepatide users reporting mid-week hunger returnMore consistent levels; harder to schedule; off-label
    Every Other Day (Q2D)Retatrutide users; experimental protocolsFlattest plasma curve; most injections; no trial data

    Frequently Asked Questions

    How often do you inject semaglutide?

    Semaglutide (Ozempic, Wegovy) is injected once weekly on the same day each week. The long half-life of approximately 7 days allows for stable blood levels with weekly dosing. You can inject at any time of day, with or without food.

    What is the tirzepatide dosing schedule?

    Tirzepatide (Mounjaro, Zepbound) follows a weekly injection schedule. Start at 2.5mg weekly for 4 weeks, then increase to 5mg. Continue escalating every 4 weeks through 7.5mg, 10mg, 12.5mg, to a maximum of 15mg based on tolerance and response.

    How long does each dose escalation phase last?

    Each dose step typically lasts 4 weeks minimum. This allows your body to adjust and reduces GI side effects. Never increase faster than every 4 weeks. If you experience significant nausea or vomiting, stay at the current dose for 8 weeks before escalating.

    What happens if I miss a dose of GLP-1?

    If you miss a dose and it has been less than 5 days (for weekly dosing), take the dose as soon as possible. If more than 5 days have passed, skip the missed dose and take the next dose on your regular day. Do not double up doses.

    Can I inject GLP-1 medications twice weekly?

    Some practitioners use twice-weekly protocols to reduce peak-related side effects or provide more consistent appetite suppression. For example, splitting a 2.4mg semaglutide dose into two 1.2mg injections. This is off-label but can improve tolerability for some users.

    What time of day should I inject GLP-1?

    There is no required time—inject when convenient and consistent. However, if you experience nausea, injecting in the evening allows you to sleep through the peak nausea window. If energy dips are an issue, morning injection may work better. Most important is consistency.

    How do I know when to increase my GLP-1 dose?

    Increase your dose when: 1) You have completed 4+ weeks at current dose, 2) Side effects have stabilized, 3) Appetite suppression is weakening or weight loss has stalled for 2+ weeks, 4) You have not reached your target weight. Do not increase if you are still losing weight or experiencing significant GI symptoms.

    Dose Escalation Schedules

    Semaglutide (Ozempic, Wegovy)

    GLP-1 Receptor Activation

    ›
    DoseWeeksExpected LossNotes
    0.25 mg0–4~1%Early titration
    0.5 mg4–82–3%Appetite suppression begins
    1.0 mg8–124–6%Noticeable trajectory
    1.7 mg12–167–9%Most reach ≥5%
    2.4 mg16–6812–15%Full effect

    Trial source: STEP-1•68 weeks•Non-diabetic obesity

    Tirzepatide (Mounjaro, Zepbound)

    Dual GIP/GLP-1 Receptor Activation

    ›
    DoseWeeksExpected LossNotes
    2.5 mg0–4~2%Starting dose
    5 mg4–84–6%Entry therapeutic
    7.5 mg8–128–10%Building
    10 mg12–1612–15%Strong effect
    15 mg16–7218–21%Maximum dose

    Trial source: SURMOUNT-1•72 weeks•Non-diabetic obesity

    Retatrutide (Investigational (Phase 2))

    Triple Agonist: GLP-1 / GIP / Glucagon

    ›
    DoseWeeksExpected LossNotes
    0.5–1 mg0–4~3%Activation phase
    2 mg4–85–7%Early response
    4 mg8–1210–12%Similar to full sema
    8 mg12–2418–20%Large effect
    12 mg24–4822–24%Maximum; no plateau

    Trial source: Phase 2 (NEJM 2023)•48 weeks•Type 2 diabetes

    References

    Medical Disclaimer

    The content in this GLP-1 dosing tool is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before beginning any new protocol, supplement, or medication.