Peptides 101

Start here. Plain-English foundations for reading peptide research critically.

What are peptides?

Peptides are short chains of amino acids that act as signals in the body.

Peptides vs proteins

The line between peptide and protein is mostly about length and folding.

How peptide drugs are developed

From mechanism and preclinical work to human trials and approval.

Routes studied in peptide research

Injection, nasal, oral, and topical — why route matters.

Peptide half-life explained

Why many peptides are cleared quickly, and how that's engineered around.

Purity, sterility, and Certificates of Analysis

Why '99% pure' on a COA does not mean 'safe'.

Why animal evidence isn't human evidence

Most peptide hype rests on animal data that may not translate.

Approved drugs vs research compounds

The most important distinction on this site.

Keep reading
Peptide classes

How compounds group by structure and target.

Mechanisms

The pathways peptides act through.

Glossary

Plain-language definitions for every term.

The tier board

Put the concepts to work — rank by evidence.

Browse by goal

Find compounds studied for a given outcome.

The all-in-one peptide app

Stop reading, start tracking.

PepCue logs your doses, runs the vial math, counts your vials, and keeps the whole protocol in one place. It replaces the spreadsheet, the calculator, and the sticky notes.

  • Dose logging
  • Reconstitution math
  • Smart reminders
  • Vial & cost tracking
iPhone · free to start