Updated 2026-10-05 · Reviewed for accuracy by the EKO Labs team. Educational only; not medical advice.

Words you will hear when talking with a doctor or pharmacist about GLP-1 medicines and peptides, explained in one or two sentences each.

Medicines and how they work

Peptide: a short chain of amino acids, the building blocks of proteins. Insulin and GLP-1 are natural peptides.
GLP-1 (glucagon-like peptide-1): a hormone the gut releases after eating. It helps release insulin, slows stomach emptying and signals fullness.
GLP-1 receptor agonist: a medicine that acts like GLP-1, such as semaglutide, liraglutide or dulaglutide.
GIP: another gut hormone. Tirzepatide acts on both GIP and GLP-1 receptors.
Insulin: the hormone that moves sugar from the blood into the body's cells.
A1C: a blood test that shows your average blood sugar over about three months.
Lipodystrophy: an abnormal change in where the body stores fat. Tesamorelin is approved for a form linked to HIV.

Safety words

Boxed warning: the FDA's strongest warning, printed in a box on a medicine's label. GLP-1 medicines carry one about thyroid C-cell tumors.
Medullary thyroid carcinoma (MTC): a rare thyroid cancer. People with a personal or family history should not use GLP-1 medicines.
MEN 2: multiple endocrine neoplasia type 2, an inherited condition that raises the risk of MTC.
Pancreatitis: inflammation of the pancreas. Severe stomach pain that does not go away needs urgent care.
Contraindication: a reason a person should not take a medicine.

FDA-approved: the FDA reviewed the medicine's safety and effectiveness for a specific use.
Brand-name medicine: the version sold by the company that got FDA approval, for example Ozempic® or Mounjaro®.
Compounded medicine: a version prepared by a licensed pharmacy for a specific patient's prescription. It is not itself FDA-approved.
503A / 503B pharmacy: the two federal categories of compounding pharmacies; 503A makes patient-specific prescriptions, 503B outsourcing facilities make larger batches under FDA oversight.
Prescribing information (label): the official FDA document for a medicine, with its uses, warnings and side effects.
"Research use only" (RUO): a label on chemicals sold for laboratory work. These products are not made or approved for people.

Telehealth: a medical visit by video or phone.
Licensed in your state: U.S. doctors may treat patients only in states where they hold a license, so the doctor you see must be licensed where you live.
HIPAA: the U.S. law that protects the privacy of your health information.

Have questions about your situation?

Talk to our team. A licensed doctor makes every medical decision.