Question 1

What happened to Peptide Sciences?

Accepted Answer

PeptideSciences.com ceased operations in early 2026 due to increasing FDA regulatory pressure and quality control concerns that affected several peptide suppliers. The shutdown created a significant gap in the research peptide supply chain. PeptideSciences.ai was created as an independent educational resource to provide researchers and consumers with reliable, science-backed information about peptides, supplier evaluation, and regulatory compliance.

Question 2

Are peptides legal in the United States?

Accepted Answer

The legality of peptides depends on the specific peptide and its intended use. FDA-approved peptide drugs (like semaglutide) are legal with a prescription. Research peptides can be legally sold for legitimate laboratory use. However, marketing research peptides for human consumption is illegal. The safest legal pathway for personal use is through a licensed healthcare provider or telehealth consultation with a prescription filled by a licensed pharmacy.

Question 3

How do I verify peptide purity?

Accepted Answer

Request a batch-specific Certificate of Analysis (COA) from your supplier. A legitimate COA should include HPLC purity results (95%+ for research grade), mass spectrometry identity confirmation, the testing laboratory's name and accreditation, and a batch number matching your product. You can verify authenticity by contacting the listed laboratory directly or submitting samples for independent third-party testing.

Question 4

What is the difference between research peptides and prescription peptides?

Accepted Answer

Research peptides are sold for laboratory use only, typically at 95-98% purity, and are not approved for human consumption. Prescription peptides are pharmaceutical-grade (99%+ purity), manufactured under GMP conditions, prescribed by licensed healthcare providers, and legally approved for human use. The clinical pathway offers medical oversight, higher quality assurance, and legal protection.

Question 5

How do I choose a reliable peptide supplier?

Accepted Answer

Evaluate suppliers based on five key criteria: (1) Batch-specific COA documentation from accredited labs, (2) Third-party testing verification, (3) Transparency about business registration and sourcing, (4) Regulatory compliance with no unauthorized health claims, and (5) Verifiable reputation with customer reviews. Avoid suppliers with unusually low prices, no COA documentation, or medical/therapeutic claims.

Question 6

What is PeptideGPT?

Accepted Answer

PeptideGPT is our AI-powered peptide research assistant that provides instant, science-backed answers to questions about peptide mechanisms, research findings, safety profiles, and more. It draws on published research and clinical data to deliver accurate, referenced information. PeptideGPT is an educational tool and does not provide medical advice.

Question 7

Why is the FDA cracking down on peptides?

Accepted Answer

The FDA has increased enforcement due to rapid market growth attracting bad actors, quality control failures revealing contaminated or mislabeled products, unauthorized health claims by sellers, and consumer safety risks from unregulated products. This has led to more warning letters, import alerts, and coordination with state agencies. The trend is moving the industry toward higher standards and greater accountability.

Question 8

Is it safe to buy peptides online?

Accepted Answer

Safety depends entirely on the source. For personal health use, the safest option is obtaining peptides through a licensed healthcare provider and pharmacy. For research purposes, safety means verifying supplier quality through COA documentation, third-party testing, and established reputation. Avoid sources that make medical claims, lack documentation, or offer prices significantly below market average.