Definitions
Peptide and GLP-1 glossary
This glossary defines 40 terms that appear on labels, calculators and tracking records. Definitions explain what a term means and what it does not prove. They do not select an amount, product or schedule.
Reconstitution solution
A reconstitution solution is the measured liquid added to a dry or lyophilised material so that its mass can be expressed as a concentration.
Definition
Bacteriostatic water
Bacteriostatic water is sterile water for injection that contains a preservative, commonly benzyl alcohol, and is packaged for repeated withdrawals under its labelled conditions.
Definition
Sterile water
Sterile water for injection is water prepared to meet sterility standards and generally contains no antimicrobial preservative.
Definition
BAC water vs sterile water
BAC water and sterile water are both sterile diluents at manufacture, but BAC water contains a bacteriostatic preservative while plain sterile water does not.
Definition
Lyophilized
Lyophilized means freeze-dried: water is removed from a frozen material under reduced pressure, leaving a dry cake, film or powder.
Definition
Reconstitution
Reconstitution is the process of adding a specified liquid to a dry product to create a measurable solution or suspension.
Definition
Diluent
A diluent is a liquid used to reduce concentration or reconstitute a dry material according to an applicable label or instruction.
Definition
Concentration
Concentration expresses how much mass is present in a given volume, commonly mg/mL or mcg/mL in this site's calculators.
Definition
Milligram
A milligram is one-thousandth of a gram and is abbreviated mg.
Definition
Microgram
A microgram is one-millionth of a gram and one-thousandth of a milligram, abbreviated mcg or µg.
Definition
Milliliter
A millilitre is one-thousandth of a litre and is abbreviated mL.
Definition
U-100 syringe
A U-100 insulin syringe is calibrated so that 100 marked units correspond to 1 mL of liquid volume.
Definition
Syringe unit
A syringe unit is a graduation printed on a calibrated barrel and represents volume under that syringe's stated calibration.
Definition
Insulin syringe sizes
Insulin syringe sizes describe barrel capacity and calibration, such as 0.3 mL, 0.5 mL or 1 mL U-100 devices.
Definition
Syringe dead space
Syringe dead space is the small internal volume that can retain liquid after the plunger is fully depressed.
Definition
Vial
A vial is a small sealed container used for a dry material or liquid product, usually closed with a stopper and cap.
Definition
Multi-dose vial
A multi-dose vial is labelled to permit more than one withdrawal under the product's stated storage and handling conditions.
Definition
Single-dose vial
A single-dose vial is labelled for use as one container for one patient in one procedure or according to its specific instructions.
Definition
Peptide
A peptide is a chain of amino acids linked by peptide bonds, generally shorter than proteins in common scientific usage.
Definition
Amino acid
An amino acid is an organic molecule containing amino and carboxyl functional groups and serves as a building block of peptides and proteins.
Definition
Peptide bond
A peptide bond is the covalent amide linkage formed between amino acids in a peptide chain.
Definition
Molecular weight
Molecular weight is the relative mass of a molecule, commonly reported as grams per mole for practical chemical records.
Definition
CAS number
A CAS Registry Number is a numeric identifier assigned to a specific chemical substance by Chemical Abstracts Service.
Definition
Half-life
Half-life is the time associated with a quantity falling to one half of its earlier value under a stated model or measurement context.
Definition
Steady state
Steady state describes a repeated-input model in which average input and elimination approach a stable pattern over time.
Definition
First-order elimination
First-order elimination is a model in which a constant fraction of the measured quantity is removed per unit of time.
Definition
Bioavailability
Bioavailability is the fraction and rate at which an administered substance reaches systemic circulation under a defined route and formulation.
Definition
Cold chain
Cold chain is the controlled temperature path used during storage and transport for temperature-sensitive products.
Definition
Freeze-thaw cycle
A freeze-thaw cycle is one complete transition from frozen to thawed conditions, often tracked for temperature-sensitive materials.
Definition
Beyond-use date
A beyond-use date is a date assigned to a prepared or compounded item based on its preparation, packaging, storage and applicable standards.
Definition
Expiration date
An expiration date is the manufacturer's labelled date through which an unopened product is expected to meet specifications when stored as directed.
Definition
Lot number
A lot number identifies a defined production lot so manufacturing and distribution records can be traced.
Definition
Batch number
A batch number is a production identifier often used similarly to lot number, though a manufacturer's terminology and scope can differ.
Definition
Route of administration
Route of administration describes how a product enters or is applied to the body, such as oral, nasal, topical or injection routes.
Definition
Subcutaneous
Subcutaneous describes the tissue layer beneath the skin and is also used as a route label in product instructions.
Definition
Intramuscular
Intramuscular describes administration into muscle and is abbreviated IM in many records.
Definition
Injection site rotation
Injection site rotation is the practice of changing recorded body locations over successive entries according to applicable professional instructions.
Definition
Compounded drug
A compounded drug is prepared by a pharmacy or outsourcing facility for an identified need under the laws and standards that apply to that setting.
Definition
Research use only
Research use only is a label indicating that a material is supplied for research rather than approved clinical use.
Definition
GLP-1 receptor agonist
A GLP-1 receptor agonist is a compound that activates the glucagon-like peptide-1 receptor.
Definition
Frequently asked questions
Does this glossary contain dosing guidance?
No. It defines units, materials, processes and record fields. Linked calculators convert values entered by the user and do not choose an amount or schedule.
Why link glossary terms to calculators?
The link shows where a term affects arithmetic and where it remains descriptive. This prevents words such as units, concentration and half-life from being treated as interchangeable.
Which term should I read first?
Start with reconstitution solution, concentration, milligram, microgram and U-100 syringe. Together they explain the inputs and outputs used by the calculator pages.
Log it once, keep it forever
PepCycle turns the numbers on this page into a running record: every dose, vial, site and side effect in one place — stored on your iPhone and backed up to your own iCloud.
Free to download · No account required · Price shown before you enter anything personal