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Two ways to support weight loss. One clinician to help you choose.

Semaglutide works on one appetite pathway. Tirzepatide works on two. Both are once-weekly, prescribed by licensed clinicians and compounded by a licensed 503A pharmacy.

Semaglutide from$95
Tirzepatide from$175

$100 off with code AJP_100. Tirzepatide from $175/month with a 3-month commitment. Free clinician consultation included.

Compare both treatments Not sure? Find your starting point
Compounded semaglutide vial from AJ Peptide Compounded tirzepatide vial from AJ Peptide

One pathway or two

Your gut releases two hormones after you eat: GLP-1 and GIP. Together they help signal fullness, slow digestion, and support healthy blood sugar.

Semaglutide acts on the GLP-1 receptor. Tirzepatide acts on both the GLP-1 and GIP receptors. That second pathway is the main difference between them, and it's one reason the two medicines performed differently in clinical trials.

Semaglutide single agonist GLP-1 GIP Tirzepatide dual agonist GLP-1 GIP

Where are you starting from?

Pick the one that sounds most like you.

You don't need to pick a medication before you start. In your online questionnaire you'll share your health history and goals, and a licensed clinician will recommend semaglutide or tirzepatide based on what fits you.

Either way, treatment starts at a low dose and increases gradually, which helps your body adjust and keeps side effects like nausea more manageable.

Start your free evaluation

Tell your clinician which medication you took, your most recent dose, and how you felt on it. They can help you continue where it makes sense or talk through switching from semaglutide to tirzepatide.

If you've had a gap in treatment, your clinician may restart at a lower dose. That's normal and helps limit side effects.

Continue with a free evaluation

That's a good place to be. Scroll down to compare the two medications side by side, see what the first few weeks look like, and read answers to common questions.

When you're ready, the clinician consultation is free and your clinician can answer questions as part of your review.

Read common questions

Semaglutide and tirzepatide

Both are once-weekly injections that help you feel full sooner and stay full longer. They differ in how many pathways they act on and in how much weight people lost in the clinical trials of the FDA-approved versions. Your clinician will help you choose.

Semaglutide

The established GLP-1 option

14.9%average body-weight reduction at 68 weeks in the STEP 1 trial of FDA-approved semaglutide 2.4 mg (Wegovy®), vs. 2.4% with placebo1

What it is

A GLP-1 receptor agonist. It mimics GLP-1, a natural gut hormone, and is modified to last about a week in the body.

Potential benefits

  • Reduces appetite and increases fullness1,6
  • Supports meaningful weight loss alongside diet and activity1
  • Improves blood sugar control6
  • The longest track record of the two

How it's used

A small injection under the skin once a week. Your clinician starts you at a low dose and increases it gradually. In trials, much of the weight returned after treatment stopped, so results depend on continued use.4

$95 first order$195
Limited-time offer: use code AJP_100 for $100 off
Start your Semaglutide evaluation

Includes a free consultation with a licensed clinician. Prescription required.

Tirzepatide

The dual-pathway option

20.9%average body-weight reduction at 72 weeks on the highest dose in the SURMOUNT-1 trial of FDA-approved tirzepatide (Zepbound®), vs. 3.1% with placebo2

What it is

A dual GIP and GLP-1 receptor agonist. A single molecule that acts on both gut-hormone pathways, also modified to last about a week.

Potential benefits

  • Acts on two appetite and metabolic pathways2,7
  • Greater average weight loss than semaglutide in a head-to-head trial3
  • Improves blood sugar control7
  • An option if semaglutide hasn't been enough for you

How it's used

A small injection under the skin once a week. Your clinician starts you at a low dose and increases it gradually. In trials, much of the weight returned after treatment stopped, so results depend on continued use.5

$185 first month$285

Or $175/month with a 3-month commitment

Limited-time offer: use code AJP_100 for $100 off
Start your Tirzepatide evaluation

Includes a free consultation with a licensed clinician. Prescription required.

Trial results above are from the FDA-approved medications in adults with obesity, or overweight with a weight-related condition, without diabetes. Compounded semaglutide and tirzepatide were not studied in these trials and are not FDA-approved. Individual results vary.

How they compare

How it worksSemaglutideGLP-1 receptor (single pathway)TirzepatideGLP-1 and GIP receptors (dual pathway)
How oftenSemaglutideOnce weeklyTirzepatideOnce weekly
Head-to-head trial3Semaglutide13.7% average weight loss at 72 weeksTirzepatide20.2% average weight loss at 72 weeks
Common side effectsSemaglutideNausea, diarrhea, constipation, vomiting, mostly early and during dose increasesTirzepatideSimilar digestive side effects, mostly early and during dose increases
Track recordSemaglutideApproved for diabetes since 2017, for weight management since 2021TirzepatideApproved for diabetes since 2022, for weight management since 2023
Limited-time priceSemaglutide$95 first order (code AJP_100)Tirzepatide$185 first month, or $175/month with a 3-month commitment (code AJP_100)

Head-to-head results are from the SURMOUNT-5 trial comparing the FDA-approved versions at their maximum tolerated doses. Approval dates refer to the FDA-approved brand medications.

What your first months look like

GLP-1 treatment is gradual by design. Here's what most people can expect.

Week 1

You start at a low dose. Many people notice less hunger and feel full sooner.

Weeks 2 to 4

Your body adjusts. Mild nausea is common early on and usually eases. Smaller meals help.

Every 4 weeks

Your clinician checks in and may increase your dose based on how you're feeling and progressing.

Month 3 and beyond

Progress tends to build over months, not weeks. Your clinician adjusts your plan as you go.

How it works

  1. Start your evaluation onlineAnswer a short health questionnaire about your history and goals.
  2. Free clinician reviewA licensed clinician reviews your answers, recommends semaglutide or tirzepatide if appropriate, and may ask follow-up questions. There's no charge for the consultation.
  3. Prescribed and compoundedYour prescription goes to a licensed 503A pharmacy that compounds it and releases it with a Certificate of Analysis.
  4. Delivered ready to useYour medication ships to your door in solution, with no mixing needed, along with instructions for use.
  5. Ongoing supportYour clinician is available for questions, dose adjustments, and refills as treatment continues.
Free clinician consultEvery prescription starts with an evaluation by a licensed clinician.
Ready to useDelivered in solution. No mixing or reconstitution.
Licensed 503A pharmacyCompounded by a named, licensed U.S. pharmacy with a Certificate of Analysis.
Ships to all 50 statesLicensed prescribers and pharmacy shipping nationwide.

Common questions

Is this the same as Ozempic, Wegovy, Mounjaro or Zepbound?

No. Those are FDA-approved brand-name medications. AJ Peptide's semaglutide and tirzepatide are compounded medications, prepared by a licensed 503A pharmacy for you based on your clinician's prescription. Compounded drugs are not FDA-approved and have not been evaluated by the FDA for safety, effectiveness, or quality.

Which one is right for me?

That's a decision you make with your clinician. They'll consider your goals, health history, any GLP-1 medication you've taken before, and how you tolerate side effects. You don't need to choose before you start your evaluation.

How much weight will I lose?

It varies from person to person. Results depend on your dose, how long you stay on treatment, and changes to eating and activity. The trial results on this page are averages from studies of the FDA-approved medications and are not a promise of individual results.

What happens if I stop?

In clinical trials, people who stopped treatment regained much of the weight they had lost.4,5 Talk with your clinician before stopping so you can plan next steps together.

Do I have to mix anything?

No. Your medication arrives in solution, ready to use, with instructions for injecting at home.

Who makes my medication?

Your prescription is compounded by one of our partner pharmacies, OptioRx or VialsRx, both licensed U.S. 503A compounding pharmacies. Each batch is released with a Certificate of Analysis.

Important safety information

Risk of thyroid C-cell tumors: In studies in rodents, semaglutide and tirzepatide caused thyroid C-cell tumors. It is not known whether they cause these tumors, including medullary thyroid carcinoma (MTC), in people. Do not use if you or a family member has had MTC, or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Tell your clinician if you notice a lump or swelling in your neck, trouble swallowing, hoarseness, or shortness of breath.

Who should not use these medications: people with a personal or family history of MTC or MEN 2, people who are pregnant or planning pregnancy, and people with a serious allergic reaction to semaglutide, tirzepatide, or any ingredient.

Serious side effects can include: inflammation of the pancreas (severe stomach pain that may spread to the back); gallbladder problems; low blood sugar, especially with insulin or sulfonylureas; kidney problems from dehydration caused by vomiting or diarrhea; serious allergic reactions; changes in vision in people with diabetes; and depression or thoughts of self-harm. These medications slow stomach emptying, which can raise the risk of inhaling food or liquid during anesthesia, so tell any provider before a procedure.

Common side effects: nausea, diarrhea, vomiting, constipation, stomach pain, indigestion, burping, tiredness, and injection-site reactions.

Tell your clinician if you have a history of pancreatitis, gallbladder, kidney, or stomach problems, diabetic eye disease, or depression, and about all medicines you take. Tirzepatide may make birth control pills less effective; use another method or add a backup method for 4 weeks after starting and after each dose increase.

Seek medical care right away if you have severe stomach pain, signs of a serious allergic reaction (rash, swelling of the face or throat, trouble breathing), or symptoms of low blood sugar.

This is not a complete list. Review all risks and side effects with your clinician.

References
  1. Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med. 2021;384(11):989–1002.
  2. Jastreboff AM, et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). N Engl J Med. 2022;387(3):205–216.
  3. Aronne LJ, et al. Tirzepatide as compared with semaglutide for the treatment of obesity (SURMOUNT-5). N Engl J Med. 2025;393(1):26–36.
  4. Rubino D, et al. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance (STEP 4). JAMA. 2021;325(14):1414–1425.
  5. Aronne LJ, et al. Continued treatment with tirzepatide for maintenance of weight reduction (SURMOUNT-4). JAMA. 2024;331(1):38–48.
  6. WEGOVY® (semaglutide) injection Prescribing Information. Novo Nordisk A/S.
  7. ZEPBOUND® (tirzepatide) injection Prescribing Information. Eli Lilly and Company.

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