Medical glossary

Plain-English definitions of 28+ common medical terms, lab values, and medication classes — written so you can use them in a visit with confidence.

• A1C (Hemoglobin A1C)

  A blood test that shows your average blood sugar over the last 3 months.

• ACE Inhibitor

  A common blood-pressure medication that also protects kidneys.

• ARB (Angiotensin Receptor Blocker)

  A blood-pressure medication similar to ACE inhibitors but without the cough.

• Blood Pressure

  The force of blood against your artery walls, recorded as two numbers.

• BMI (Body Mass Index)

  A weight-for-height calculation used to screen for under- or overweight.

• Controlled Substance

  A medication regulated by the DEA because of abuse or dependence potential.

• eGFR (Estimated Glomerular Filtration Rate)

  A blood test that estimates how well your kidneys filter waste.

• EHR (Electronic Health Record)

  Your digital medical chart maintained by a clinic or hospital system.

• Ferritin

  The blood test that measures your body's stored iron.

• Formulary

  The list of medications your insurance plan covers, grouped by cost tier.

• GERD (Acid Reflux)

  Chronic backflow of stomach acid into the esophagus.

• GLP-1 (Glucagon-Like Peptide-1)

  A gut hormone — and a drug class — used for diabetes and weight loss.

• HDL Cholesterol

  The 'good' cholesterol that helps clear excess cholesterol from your blood.

• ICD-10 Code

  The international code your clinician puts on visits and prescriptions.

• LDL Cholesterol

  The 'bad' cholesterol that can build up in arteries and raise heart-attack risk.

• Metformin

  The standard first-line oral medication for type 2 diabetes.

• NPI (National Provider Identifier)

  A 10-digit federal ID number for every U.S. healthcare provider.

• PPI (Proton Pump Inhibitor)

  Acid-blocking medication used for reflux and ulcer disease.

• Prediabetes

  Blood sugar higher than normal but not yet diabetes.

• Prior Authorization

  When insurance requires approval before covering a prescription or service.

• Referral

  A note from one clinician to another that you need specialty care.

• Refill

  An additional fill of an existing prescription, up to the authorized limit.

• SSRI (Selective Serotonin Reuptake Inhibitor)

  A common first-line class of antidepressant medication.

• Statin

  A cholesterol-lowering medication that reduces heart-attack risk.

• Telehealth

  Healthcare delivered by video, phone, or messaging instead of in person.

• TSH (Thyroid Stimulating Hormone)

  The pituitary-gland hormone used to screen for thyroid problems.

• UTI (Urinary Tract Infection)

  A bacterial infection of the bladder, urethra, or kidneys.

• Vitamin D (25-OH)

  A blood test for vitamin D status; low levels are very common.