A Guide to Peptide Therapies: What They Are and What They're Used For

Peptides have become one of the most talked-about tools in modern wellness and hormone optimization — and for good reason. These small proteins act as precise messengers in the body, and a growing number of them have earned a real place in medicine, from FDA-approved prescription drugs to compounded therapies used under a provider's care. But the space is also crowded with hype and confusion, especially about what's actually approved versus what's still investigational.

At Finger Lakes FNP, we believe patients make the best decisions when they have clear, honest information. So here's a plain-language review of many of the peptides you may have heard about, what each is used for, and — importantly — where each one stands with the FDA.

First, what exactly is a peptide?

A peptide is a short chain of amino acids, the same building blocks that make up proteins. Your body makes thousands of them naturally, and they act as signaling molecules that tell your cells what to do — regulating everything from blood sugar and appetite to tissue repair, sexual function, and growth hormone release. Peptide therapy uses these molecules (or lab-made versions of them) to nudge specific processes in a targeted way.

A crucial distinction: "approved" vs. "compounded"

This is where a lot of confusion lives, so it's worth being precise. FDA-approved peptides are drugs that have completed rigorous clinical trials and received formal approval for specific conditions — meaning their safety, effectiveness, and dosing are well established. Compounded peptides, by contrast, are prepared by licensed compounding pharmacies and prescribed by a provider, but they have not gone through FDA approval for a specific use. Many popular "wellness" peptides fall into this second category.

The regulatory landscape here is also actively changing. In February 2026, HHS announced that roughly a dozen previously restricted peptides would move back toward a category that allows licensed pharmacies to compound them again. That's meaningful for access — but it's not the same as FDA approval, and it doesn't establish proven safety or efficacy. Responsible clinics treat these therapies accordingly.

With that framing, here's the review.

FDA-approved peptide medications

These are peptides that have completed the full approval process for their listed uses.

Metabolic health and weight loss

• Semaglutide (Ozempic, Wegovy) — a GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management. It curbs appetite, slows digestion, and improves blood sugar control.

• Tirzepatide (Mounjaro, Zepbound) — a dual GIP/GLP-1 agonist approved for type 2 diabetes and weight management, often with even greater weight-loss effect.

• Liraglutide (Victoza, Saxenda) — an earlier GLP-1 agonist for diabetes and weight management.

• Setmelanotide (Imcivree) — approved for certain rare genetic forms of obesity.

Sexual health

• Bremelanotide (Vyleesi) — a melanocortin-receptor agonist approved for low sexual desire (HSDD) in premenopausal women. It acts centrally in the brain rather than on blood flow. (You may also hear it called PT-141; its use in men is off-label.)

Body composition and other hormonal uses

• Tesamorelin (Egrifta) — a growth-hormone-releasing hormone analog approved to reduce excess abdominal fat in people with HIV-associated lipodystrophy.

• Teriparatide (Forteo) and abaloparatide (Tymlos) — parathyroid-hormone peptides approved to build bone in osteoporosis.

• Octreotide and lanreotide — approved for acromegaly (growth hormone excess) and certain neuroendocrine tumors.

• Leuprolide and related GnRH analogs — used in prostate cancer, endometriosis, fibroids, and other hormone-sensitive conditions.

• Desmopressin — a vasopressin analog for diabetes insipidus and certain bleeding and bedwetting conditions.

• Linaclotide and plecanatide — approved for constipation-predominant IBS and chronic constipation.

• Insulin, glucagon, and calcitonin — foundational peptide hormones used in diabetes, hypoglycemia rescue, and bone/calcium disorders.

Compounded and clinically used peptides

These are prescription peptides commonly used in optimization and functional-medicine settings. They are prepared by compounding pharmacies and used under medical supervision, but they are not FDA-approved for these purposes, and the human evidence behind them ranges from promising to preliminary.

Growth hormone support (secretagogues)

• Sermorelin — stimulates the pituitary to release more of your own growth hormone; used to support energy, recovery, body composition, and sleep.

• Ipamorelin — a selective growth-hormone secretagogue valued for triggering GH release with minimal effect on cortisol or appetite.

• CJC-1295 — a longer-acting growth-hormone-releasing analog, often paired with ipamorelin for a steadier effect.

Tissue repair and recovery

• BPC-157 — a "body protective compound" studied for gut, tendon, ligament, and joint healing. Popular in recovery circles, though human data remain limited.

• Thymosin beta-4 / TB-500 — investigated for muscle, tendon, and soft-tissue repair.

• GHK-Cu (copper peptide) — used topically and by injection for skin health, wound healing, hair, and its antioxidant and collagen-supporting effects.

Immune and other targeted uses

• Thymosin alpha-1 — studied for immune modulation and support.

• PT-141 (bremelanotide, compounded form) — used off-label for sexual desire and arousal in both men and women.

• PT-141, Selank, Semax, and similar — a broader family explored for mood, focus, and sexual or cognitive support, all still investigational.

The bottom line on safety

Peptides can be genuinely useful tools, but they are prescription therapies — not supplements — and they deserve the same care as any medication. Purity and sourcing matter enormously (research-grade "gray market" peptides are a real risk), the evidence base varies widely from one peptide to the next, and the right candidate, dose, and monitoring depend on your individual health picture. That's exactly why these therapies belong in a supervised clinical relationship, not a self-directed experiment.

Curious whether peptide therapy is right for you?

Whether your goals are weight loss, recovery, energy, better sleep, or overall optimization, the first step is a conversation grounded in your labs, your history, and the current evidence.

Reach out to Finger Lakes FNP to explore peptide therapy, and we'll help you sort the genuine options from the hype — safely and honestly.

-Melissa Vorhis, DNP, FNP-C

This article is for educational purposes only and is not a substitute for individualized medical advice. FDA approval status and compounding regulations for peptides can change; the information here reflects the landscape as of mid-2026. Any peptide therapy should be prescribed and monitored by a qualified provider based on your specific situation.