What Are Peptides? How They Differ from GLP-1 Medications
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Peptides are short chains of amino acids that act as chemical messengers in your body, and they are behind many of the medications and wellness treatments now offered through telehealth. If you already know about GLP-1 medications like Ozempic or Wegovy, you have already been introduced to one type of peptide. But there are many others showing up in telehealth and wellness programs right now, and this article will walk you through what they are, what they do, what names you might hear them called, and what the research actually shows about each one.
Who This Helps
This article is for anyone who has started hearing words like "peptide therapy," "CJC-1295," "BPC-157," or "ipamorelin" and wants a clear, plain-language explanation of what these compounds are. It is especially helpful if you are already exploring GLP-1 options through a provider or through GLP Winner's personal provider comparison tool and want to understand what else is out there.
What Is a Peptide, Exactly?
A peptide is a short chain of amino acids. Amino acids are the building blocks your body uses to make proteins. When a few of them link together in a specific order, they form a peptide. Your body already makes thousands of them. They act like tiny instructions, telling different cells what to do.
Insulin is a peptide. So is oxytocin. Peptides help regulate everything from your appetite to your immune system to how quickly you heal from an injury.
When people talk about "peptide therapy," they mean using a specific peptide, either one your body already makes or a lab-created version of one, to support a particular function in your body. The idea is to give your body's own signaling system a targeted boost.
Most peptides have traditionally required injections because they break down too quickly in your stomach to be taken as a pill. That is part of what makes 2026 such an interesting moment:
- The FDA recently approved Foundayo (orforglipron), a daily pill that works on the same GLP-1 receptor as peptide-based medications like semaglutide (FDA). Foundayo itself is actually a small molecule, not a peptide, which is exactly why it can survive your stomach acid without any special protection.
- Meanwhile, the oral Wegovy pill (which is semaglutide, and is a peptide) also became available, using a compound called SNAC that buffers the pH in your stomach to shield the peptide from digestive enzymes and help it cross the stomach lining into your bloodstream (NIH).
Together, these approvals point toward a future where more treatments in this space come in pill form rather than as injections.
GLP-1 Medications: The Peptides You Probably Already Know
These are the most widely prescribed peptides in telehealth today, and the ones that put peptides on the map for most people. All of the medications in this section are FDA-approved and available by prescription through your provider.
Ozempic and Wegovy (semaglutide). Semaglutide is a GLP-1 receptor agonist, which is the medical term for a medication that activates a receptor in your body that helps with blood sugar and appetite. After that first explanation, we will just call these "GLP-1 medications" for simplicity. Ozempic is FDA-approved for type 2 diabetes. Wegovy is FDA-approved for weight management and is now also available as a daily pill (FDA).
- Large clinical trials showed the injectable form produced about 14.9% average weight loss, and the oral pill showed about 16.6% in studies where patients stayed on treatment (Novo Nordisk).
- Common side effects include nausea, vomiting, and diarrhea, which are usually mild and tend to improve over time.
- These are prescription medications and should only be taken under a provider's guidance.
Mounjaro and Zepbound (tirzepatide). Tirzepatide is a dual GIP/GLP-1 receptor agonist. That means it activates two receptors instead of one, which is one reason clinical trials have shown strong results. Mounjaro is FDA-approved for type 2 diabetes. Zepbound is FDA-approved for weight management. Both are given as weekly injections. Like semaglutide, the most common side effects are stomach-related, and these are prescription medications requiring a provider's evaluation.
Saxenda (liraglutide). This is an older daily-injection GLP-1 medication for weight management. It was FDA-approved in 2014 (FDA) and is still prescribed, but semaglutide and tirzepatide have largely become the more common choices because of stronger results and more convenient dosing. Prescription required.
Foundayo (orforglipron). This one deserves a special note. The FDA approved Foundayo in April 2026 (FDA). Foundayo is not a peptide. It is a small molecule that activates the same GLP-1 receptor. Because it is not a peptide, your stomach acid does not break it down, which means it can be taken as a simple daily pill with no food or water restrictions.
- In clinical trials, participants at the highest dose achieved about 12.4% average weight loss (FDA).
- We mention it here because you will almost certainly hear it alongside peptide names, and it is worth knowing the difference.
- You can read more about Foundayo in GLP Winner's full breakdown of the approval. Prescription required.
If you are exploring GLP-1 options and want to compare what different providers charge, GLP Winner's personal provider comparison tool can help you see your options side by side.
What This Means for You
The GLP-1 category now includes both injectable and oral options. If needles have been a barrier for you, the approval of Foundayo and the oral Wegovy pill means there are now pill-based paths to consider. Your provider can help you decide which format and medication fits best.
Growth Hormone Peptides: Recovery, Sleep, and Body Composition
This is the second-largest group of peptides you will see offered in telehealth wellness programs. These peptides work by encouraging your pituitary gland (a small gland at the base of your brain) to release more of its own growth hormone. They do not introduce synthetic growth hormone directly.
The goal for most people interested in these peptides is better recovery from exercise, improved sleep, less body fat, and more lean muscle. None of the peptides in this section (except tesamorelin) are FDA-approved, and all should be used under a provider's guidance with appropriate lab monitoring, typically including IGF-1 blood levels.
Sermorelin. This is one of the most commonly prescribed peptides in anti-aging and wellness clinics. Sermorelin is a lab-made version of the signal your brain naturally sends to trigger growth hormone release.
- It was originally FDA-approved in 1997 under the brand name Geref for treating growth hormone deficiency in children. The manufacturer voluntarily discontinued it in 2008 due to manufacturing difficulties, not because of safety concerns (Federal Register).
- Human studies confirmed it effectively stimulates growth hormone release, and its safety profile during its years as an FDA-approved product was well established.
- Today it is available through licensed compounding pharmacies by prescription and is typically given as a daily injection.
CJC-1295. This works in a similar way to sermorelin but has been chemically modified to last longer in the body. It comes in two forms: one version includes something called DAC (Drug Affinity Complex), which keeps it active for several days, and the other version, without DAC, creates shorter pulses of growth hormone release.
- A human study in healthy adults found that a single injection increased growth hormone levels 2 to 10 times above baseline for six or more days (PubMed).
- One clinical trial was halted after a participant death, though the attending physician believed it was unrelated to the peptide and likely caused by an undiagnosed heart condition.
- CJC-1295 is not FDA-approved but is available through licensed compounding pharmacies by prescription.
Ipamorelin. This peptide takes a different approach. Instead of mimicking the growth hormone release signal, ipamorelin works on ghrelin receptors (ghrelin is sometimes called the "hunger hormone"). What makes ipamorelin popular is that it stimulates growth hormone without significantly raising cortisol or other stress hormones, which means it tends to have fewer side effects.
- A 1999 human trial in healthy male volunteers confirmed ipamorelin stimulates growth hormone at levels considered biologically effective, with peak secretion within one hour of administration (PubMed).
- Ipamorelin is not FDA-approved but is available through licensed compounding pharmacies by prescription.
CJC-1295 and ipamorelin together. You will very often see these two prescribed as a combination, sometimes called a "stack." Because they work through different pathways, they can support each other's effects. This is one of the most commonly requested peptide combinations in telehealth programs. People who use this combination typically report improved sleep within the first few weeks, with changes in body composition becoming more noticeable after two to three months. While each peptide has individual human data, the combination itself has mainly been studied in animal models.
Tesamorelin (Egrifta SV). This is the only growth hormone peptide in this group with current FDA approval. It was approved in 2010 specifically for reducing excess belly fat in people living with HIV-related lipodystrophy (FDA). It is a prescription medication. Some wellness providers prescribe it off-label for fat reduction in other situations.
Important safety note. Growth hormone peptides like sermorelin, tesamorelin, and CJC-1295 are generally not recommended for people with active cancer or a personal or family history of cancer, because stimulating growth hormone could potentially promote tumor growth (NIH). This is something your provider should discuss with you before prescribing.
Healing and Recovery Peptides
These peptides have generated enormous interest from athletes, people dealing with injuries, and anyone looking for support with chronic pain or gut health. The regulatory picture here has been complicated, though it is actively evolving.
BPC-157 (Body Protection Compound-157). This is probably the most talked-about peptide in the recovery space. BPC-157 is a synthetic version of a short protein sequence found naturally in your stomach juice.
- Hundreds of animal studies suggest it may help with tissue healing, gut protection, and reducing inflammation, but no completed human clinical trials exist to confirm these findings in people.
- In 2023, the FDA added BPC-157 to a list of substances that compounding pharmacies could no longer produce, citing a lack of human safety data (FDA).
- In February 2026, the administration announced plans to reclassify BPC-157 and restore legal compounding access through licensed pharmacies with a prescription, though formal implementation is still pending.
- Until that is finalized, BPC-157 is primarily found through grey market sources. If you see it being sold online without a prescription, that is a risk. Without verified purity and sterility, injectable peptides from unregulated sources can cause infections ranging from minor skin reactions to serious conditions requiring hospitalization.
TB-500 (Thymosin Beta-4 fragment). TB-500 is a lab-made version of part of a protein called Thymosin Beta-4, which is found in nearly all human cells and plays a role in tissue repair. Where BPC-157 research focuses on building new blood vessels at an injury site, TB-500 research focuses on helping cells move to where they are needed for healing.
- Animal studies have shown thymosin beta-4 accelerates wound healing and increases collagen deposition, and two small phase 2 human trials in stasis and pressure ulcers found it accelerated healing compared to controls (PubMed). Beyond wound care, the broader recovery claims popular in fitness communities remain supported only by animal data.
- TB-500 was also placed on the FDA's restricted list in 2023 and is expected to be reclassified for legal compounding access pending formal implementation.
- Until then, it is primarily sourced through grey market channels and carries the same contamination and quality risks as any unregulated peptide.
- These two peptides were often used together before the restrictions, and that combination remains one of the most commonly discussed in recovery-focused communities.
Immune Support Peptides
Thymosin Alpha-1 (Ta1). Your thymus gland (a small organ behind your breastbone) naturally produces this peptide. It helps activate certain immune cells called T-cells and helps balance your immune response.
- Thymosin Alpha-1 has been approved by regulatory agencies in more than 35 countries (marketed as Zadaxin) for treating chronic hepatitis B and as an immune-boosting therapy. It is not approved by the FDA here in the United States.
- Extensive human clinical data exists, including studies showing it can improve immune response in people with hepatitis B and certain cancers (NIH).
- In the U.S., it was placed on the FDA's Category 2 list and is expected to be reclassified for legal compounding under pending changes. Until then, availability through licensed compounding pharmacies may be limited.
- Your provider should evaluate whether it is appropriate for you based on your health history.
Fat Loss Peptides Beyond GLP-1s
AOD-9604. This peptide is a modified fragment of human growth hormone, specifically a small piece (positions 176 through 191) that researchers believed might retain fat-burning properties without the muscle-building or blood-sugar effects of full growth hormone.
- Human clinical trials have been conducted. Early smaller studies showed modest weight loss compared to placebo, but the largest trial (536 participants over 24 weeks) failed to show a statistically significant difference, and development was abandoned in 2007 (NIH).
- On the safety side, across six controlled trials involving more than 900 participants, AOD-9604 was well tolerated with minimal side effects (NIH).
- It received GRAS (Generally Recognized as Safe) status from the FDA in 2021 as a food ingredient, though that is a different regulatory category than approval as a medication.
- AOD-9604 is not FDA-approved as a drug. It is available through licensed compounding pharmacies by prescription and is expected to be reclassified under pending changes. Your provider should help you weigh the limited efficacy evidence against your goals.
Skin, Hair, and Cosmetic Peptides
GHK-Cu (Copper Peptide). This is a naturally occurring peptide that has been circulating in your blood since birth. It is just three amino acids long, bound to a copper molecule. GHK-Cu was first identified in 1973 and has been studied for its ability to stimulate collagen and elastin production, support wound healing, and promote hair growth (NIH).
- Early animal studies have shown results comparable to minoxidil 5% (the active ingredient in Rogaine) for stimulating hair follicle activity, though large-scale human trials comparing the two have not been completed.
- A human trial of 71 women with signs of photoaging found that a GHK-Cu facial cream applied for 12 weeks increased skin density and thickness while reducing fine lines and wrinkle depth (NIH).
- GHK-Cu is available as a topical product (serums, creams) that you can buy over the counter without a prescription. Injectable versions are available through licensed compounding pharmacies by prescription.
- Topical use is generally considered safe. Injectable use should be monitored by a provider.
Sexual Health Peptides
PT-141 (bremelanotide, brand name Vyleesi). Unlike most sexual health medications that work on blood flow, PT-141 acts on receptors in the brain called melanocortin receptors to stimulate sexual desire.
- Vyleesi was FDA-approved in 2019 for treating hypoactive sexual desire disorder (HSDD) in premenopausal women, based on two large clinical trials involving over 1,200 women (FDA).
- Common side effects include nausea, flushing, and headache.
- It is given as a shot under the skin and is a prescription medication. Compounding pharmacies also produce it for off-label use, but you should discuss any use with your provider.
Do You Need a Prescription for Peptides?
The short answer: for any peptide you plan to inject or take as a therapeutic treatment, you should be working with a licensed provider who can evaluate whether it is appropriate for you and write a prescription.
Here is how it breaks down:
- FDA-approved peptide medications (like semaglutide, tirzepatide, bremelanotide, and tesamorelin) always require a prescription.
- Compounded peptides (like sermorelin, CJC-1295, ipamorelin, and others) require a prescription from a licensed provider to obtain from a legitimate 503A or 503B compounding pharmacy.
- Grey market peptides can be purchased without a prescription, but this is not recommended and comes with significant quality and safety risks (more on that below).
Even if a peptide has a generally favorable safety profile, you need a provider who can:
- Check for contraindications (like cancer history with growth hormone peptides)
- Order the right lab work to monitor your response
- Adjust dosing based on how your body reacts
At the very least, if you are already taking any peptide on your own, let your doctor know so they can factor it into your overall care.
What About Compounded Peptides vs. Supplements?
This is an important distinction that every peptide buyer should understand. Compounded peptides from licensed pharmacies are not the same as over-the-counter supplements or unregulated products sold online.
Licensed compounding pharmacies (503A and 503B) operate within established legal and regulatory frameworks:
- 503A pharmacies compound medications based on individual prescriptions from a licensed provider and are regulated by state boards of pharmacy.
- 503B outsourcing facilities are registered with the FDA and subject to FDA manufacturing standards and inspections (FDA).
- You can learn more about the difference between these pharmacy types in GLP Winner's 503A vs 503B article.
Dietary supplements are a different thing entirely:
- They do not require FDA pre-market approval.
- Supplement manufacturers are responsible for their own safety and labeling claims, but the FDA does not verify these before the product reaches you.
- The phrase "FDA-registered facility" does not mean FDA-approved. Any facility that makes or packages supplements must register with the FDA, but registration does not mean the FDA has reviewed or approved what is being made there.
If you see peptides being sold as "supplements" or through sources that do not require a prescription, that is worth approaching with caution.
What Are Grey Market Peptides, and Why Should You Be Careful?
Before peptides became widely available through telehealth and licensed compounding pharmacies, many of them first gained a following through what is known as the grey market.
Peptides like BPC-157, TB-500, and CJC-1295 first entered the public conversation in the 2010s, when bodybuilders and powerlifters began sourcing them from overseas websites to speed up injury recovery and build muscle (STAT News). People shared dosing guides on forums and social media, often without ever consulting a provider. By 2020, interest had expanded beyond fitness communities into mainstream wellness and biohacking, fueled in part by popular podcasts and social media influencers introducing millions of people to compounds they had never heard of (NPR). U.S. peptide imports from unregulated overseas sources nearly doubled in 2025, reaching $328 million in the first nine months alone (Preventive Medicine Daily).
Grey market peptides are typically sold online, often from overseas manufacturers, labeled "for research purposes only." They do not require a prescription and have no guaranteed quality controls.
The risks are real:
- The FDA has found that up to 40% of tested peptide products from online and compounded sources contained incorrect dosages or ingredients not listed on the label (FDA).
- Some tested samples contained no detectable target peptide at all.
- A vial can test at high purity and still be contaminated with bacterial byproducts from unsterile manufacturing. Injecting contaminated products can cause infections ranging from minor cellulitis to sepsis.
- There is no way to verify dosing accuracy, sterility, or actual contents without independent lab testing that most consumers do not have access to.
For a deeper look at grey market risks specifically, GLP Winner has a dedicated article: What Are Grey Market Peptides and Why You Should Care.
Peptides Primarily Available Through Grey Market Sources
Some peptides you may hear about are not currently available through licensed U.S. compounding pharmacies and are primarily found only through grey market channels. These carry additional risk because there is no regulated supply chain and no prescription requirement to act as a safety check. Here are a few you may encounter:
Selank and Semax. These are two synthetic peptides originally developed in Russia and popular in the cognitive performance and mood support space. Selank is studied for anti-anxiety effects. A clinical study of 62 patients with generalized anxiety disorder found its anti-anxiety effects comparable to medazepam (a benzodiazepine) but without the sedation, memory impairment, or dependence risks associated with those drugs (PubMed). Semax is studied for memory, focus, and brain protection, with human clinical research showing neuroprotective benefits in stroke recovery and increases in BDNF, a protein that supports brain cell health (PubMed). Both are approved pharmaceuticals in Russia but have not gone through FDA approval in the U.S. Large Western-style randomized controlled trials are limited. They are typically given as nasal sprays and are primarily sourced through grey market sellers and specialty research suppliers. Because they lack regulated U.S. compounding availability, there is no guaranteed way to verify purity or dosage. You should not purchase or self-administer these from unregulated sources.
Epitalon. This is a lab-made version of a peptide your pineal gland produces naturally. It has attracted interest in the longevity community because of research suggesting it may affect telomere length (the protective caps on the ends of your chromosomes that shorten as you age). Lab studies have shown epitalon can activate telomerase and increase telomere length in human cell lines (PubMed). Early research also suggests it may help regulate melatonin and improve sleep quality. However, large-scale human clinical trials have not been conducted, and most evidence comes from cell studies and research primarily out of one institute in Russia. Epitalon is not FDA-approved and is primarily found through grey market sources and research suppliers. Quality verification is a serious concern. You should not purchase or self-administer this from unregulated sources.
MOTS-c. This is produced by your mitochondria (the parts of your cells that generate energy) and plays a role in how your body regulates metabolism and responds to insulin. Human clinical evidence is extremely limited. One small phase 1 study of 20 participants using a MOTS-c analog (CB4211) showed it was well tolerated and reduced liver enzyme markers and glucose levels, but the study was only four weeks long and too small to draw firm conclusions (ClinicalTrials.gov). Long-term safety data in humans does not exist. Some licensed compounding pharmacies carry it, but availability is inconsistent and it is also found through grey market sources. You should not purchase or self-administer this from unregulated sources, and if you are interested, work with a provider who can monitor you appropriately.
Language to Watch For
When you are researching peptides online, keep an eye out for phrases that can be misleading:
- "FDA-registered" does not mean FDA-approved. Any supplement manufacturing facility must register with the FDA, but that is an administrative step, not an endorsement.
- "Pharmaceutical grade" is not a regulated term. It sounds reassuring, but anyone can use it.
- "Same ingredient as Ozempic" or "same ingredient as Wegovy" when describing a compounded product is a claim the FDA has explicitly said companies should not make. Compounded products are not FDA-approved as finished drugs (FDA).
- "Clinically proven" used for a peptide that has not completed human clinical trials is misleading. Many popular peptides have strong animal study data, but animal data and human clinical trial data are not the same thing.
- "No prescription needed" for a therapeutic peptide is a warning sign. If a seller does not require a prescription for an injectable peptide, that means you are not getting it through a licensed compounding pharmacy with proper oversight.
- "99% pure" does not mean safe. A peptide can test at high purity and still be contaminated with bacterial byproducts from unsterile manufacturing conditions. Purity testing alone does not catch everything.
- "For research purposes only" is the standard disclaimer on grey market peptides. It means the product is not intended for human use and has no regulatory oversight for safety.
Final Takeaway
Peptides are not new. Your body has been making and using them your entire life. What is new is how many of them are now available through telehealth and wellness programs, and how much more people are hearing about them.
The most important thing is to take the time to understand what each peptide does, whether it is FDA-approved or compounded, and where it is coming from. Work with a provider you trust. Ask about your pharmacy's credentials. And if something is only available from an unregulated online seller, weigh that carefully before moving forward.
This is a rapidly evolving area of medicine. More oral options are on the way. Regulatory changes are ongoing. And the better you understand the basics, the more confidently you can make decisions that are right for your health.
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