Semaglutide Injection Dosing Schedule for Weight Loss

Last reviewed: June 4, 2026

Last updated: June 4, 2026

Written by: Jay Hastings, CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

This article is part of the PlexusDx Education Hub — science-backed guidance on GLP-1 medications, metabolic health, and precision weight management.

Semaglutide injections are administered once per week, making them convenient for long-term weight management. The medication works by activating GLP-1 receptors in your brain and gut, signaling fullness and reducing appetite. Most patients follow a gradual dose-escalation protocol, starting at the lowest dose and increasing every four weeks until reaching their effective maintenance level.

Weekly Semaglutide Injection Schedule Explained

Semaglutide for weight loss requires a single subcutaneous injection once every seven days. You can inject on the same day each week—for example, every Monday morning—making it simple to remember. The injection itself takes less than one minute and uses a small needle that most patients find nearly painless. You'll inject into the abdomen, thigh, or upper arm, rotating sites each week to prevent skin irritation.

The standard treatment timeline spans 16 to 20 weeks during the initial dose-escalation phase. Your starting dose is typically 0.25 mg, with increases occurring every four weeks until you reach your target maintenance dose. This gradual approach allows your body to adapt to the medication while minimizing nausea and other gastrointestinal side effects. PlexusDx provides clear injection guidance and video tutorials to ensure you're administering each dose correctly.

Standard Semaglutide Dose Escalation Protocol

The dose-escalation plan begins at 0.25 mg weekly during weeks one through four. Week five through eight brings an increase to 0.5 mg per injection. From weeks nine through twelve, most patients move to 1.0 mg weekly. The final phase, weeks thirteen through sixteen, typically reaches 1.7 mg or 2.4 mg depending on your response and weight loss goals.

Not every patient needs to reach the highest dose to see results. Many people experience significant weight loss at 1.0 mg or 1.7 mg and choose to maintain at that level long-term. Your PlexusDx clinician will review your progress at each escalation point and may recommend staying at a lower dose if you're meeting your goals and tolerating the medication well. This personalized approach ensures you're on the minimum effective dose rather than pushing to the maximum.

How Long Do You Stay on Semaglutide Injections?

Once you reach your maintenance dose, you'll continue weekly injections indefinitely as long as the medication remains effective for your weight management goals. Semaglutide is designed for long-term use, and most clinical evidence shows sustained benefit over multiple years. Stopping the medication typically leads to weight regain within weeks to months, so ongoing treatment is part of the overall weight loss strategy.

Your PlexusDx team will monitor your progress every 4 to 12 weeks, depending on your needs and stage of treatment. Regular check-ins help identify whether your current dose is still working, if adjustments are needed, or if genetic factors—measured by the Precision Peptide Genetic Test—suggest you might benefit from a different compound like tirzepatide. Ongoing medication management ensures you stay on the most effective therapy for your unique biology.

Semaglutide Cost and Convenient Home Delivery

PlexusDx offers compounded semaglutide injections starting at $149 per month through licensed 503A compounding pharmacies. The pricing remains flat regardless of your dose level—your dose may need to go up, but your price won't. This transparent approach makes budgeting predictable and ensures affordability throughout your weight loss journey. No insurance is required, and HSA or FSA funds can be used to pay.

Your weekly injections are delivered directly to your home, eliminating trips to a pharmacy or clinic for refills. PlexusDx serves all 50 states and handles all logistics so you can focus on your treatment results. If you want to understand whether your genetic makeup favors semaglutide or a dual compound like tirzepatide, the Precision Peptide Genetic Test ($99 add-on after your first month) maps 14 pathways and 150+ genetic insights to guide your personalized therapy.

How Your Genetics Influence GLP-1 Response

Not everyone responds to GLP-1 medications the same way. Genetic variants — including GIPR rs1800437, GLP1R rs6923761, FTO rs9939609, and MC4R rs17782313 — influence how your body processes these medications, how much weight you lose, and how you tolerate side effects. PlexusDx maps 14 pathways, 49 peptides, and 150+ genetic insights to match each patient to the right medication, dose, and lifestyle protocol for their biology. The PlexusDx Precision Peptide Genetic Test ($99 add-on after your first month of treatment) gives your provider precise insight into your peptide genetic predispositions before the first prescription is written.

Access Personalized GLP-1 Care Through PlexusDx

PlexusDx offers six prescription GLP-1 protocols to all 50 states — no membership, no insurance required, async intake or live consult. The Semaglutide Injection starts at $149/mo. Medications are dispensed from licensed 503A compounding pharmacies following strict quality and safety standards. Add a Precision Peptide Genetic Test for $99 to personalize your protocol from day one.

Frequently Asked Questions

Can I change my semaglutide injection day from week to week?

It's best to inject on the same day each week to maintain consistent medication levels in your bloodstream. However, if you need to shift your injection day by a day or two occasionally, it won't cause harm. For example, you can inject on Monday one week and Tuesday the next if needed.

How quickly does semaglutide work after my first injection?

Most patients notice reduced appetite and increased fullness sensations within 3 to 5 days of the first injection. Weight loss typically becomes measurable within 2 to 4 weeks, with continued progress over subsequent months. Clinical trials show an average of 5% body weight loss by week 8 and 10-15% by week 16.

What's included in PlexusDx's $149/month semaglutide price?

PlexusDx's flat-rate pricing includes the compounded semaglutide medication, delivery to your home, and access to the PlexusDx clinical team for dosing adjustments and safety monitoring. No insurance is required, no membership fees apply, and you can use HSA or FSA funds.

Are there risks to injecting semaglutide weekly?

Weekly semaglutide injections are safe when administered as prescribed by your PlexusDx clinician. Common side effects include mild nausea, vomiting, or constipation, especially during dose escalation—these typically resolve within days to weeks.

How does the Precision Peptide Genetic Test improve my semaglutide results?

The Precision Peptide Genetic Test analyzes key variants in your GLP1R, GIPR, FTO, and MC4R genes that influence how your body responds to semaglutide and other GLP-1 therapies. If genetic data suggests weaker GLP1R signaling, your PlexusDx clinician may recommend tirzepatide or a dual compound instead.

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