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Peptide Glossary
Clear definitions for the math, vial, research, regulatory, and biology terms that appear throughout BACToBasics. The goal is to make the rest of the site easier to understand without turning definitions into dosing or treatment guidance.
6
Math & Measurement
terms in this section
5
Reconstitution & Vials
terms in this section
8
Research & Regulation
terms in this section
6
Pharmacology & Biology
terms in this section
25 terms
Math & Measurement
Concentration
The amount of a substance contained in a given volume of liquid, such as mg/mL or mcg/mL.
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Math & Measurement
Milligram (mg)
Also: mg
A unit of mass equal to one-thousandth of a gram.
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Math & Measurement
Microgram (mcg)
Also: mcg, µg, ug
A unit of mass equal to one-millionth of a gram, or one-thousandth of a milligram.
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Math & Measurement
Milliliter (mL)
Also: mL, ml
A metric unit of liquid volume equal to one-thousandth of a liter.
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Math & Measurement
U-100 Syringe Units
Also: syringe units, U-100 units, insulin syringe units
Volume markings on a U-100 insulin syringe where 100 units correspond to 1 mL of liquid.
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Math & Measurement
International Unit (IU)
Also: IU, international units
A substance-specific unit of biological activity that cannot be converted generically to mg or mcg.
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Reconstitution & Vials
Bacteriostatic Water
Also: BAC water, bacteriostatic water for injection
Sterile water for injection that contains an antimicrobial preservative intended to inhibit bacterial growth after entry into the vial.
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Reconstitution & Vials
Sterile Water
Also: sterile water for injection
Sterile water for injection that does not contain the bacteriostatic preservative found in bacteriostatic water.
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Reconstitution & Vials
Reconstitution
The process of adding a liquid to a dry or lyophilized product so that it becomes a solution or suspension with a calculable concentration.
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Reconstitution & Vials
Lyophilized
Also: freeze-dried, freeze dried
Freeze-dried: a form in which water has been removed from a product under controlled conditions.
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Reconstitution & Vials
Fixed-Ratio Blend
Also: peptide blend, pre-blended vial, multi-component vial
A single vial containing multiple labeled components in a set proportion to one another.
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Pharmacology & Biology
Peptide
A chain of amino acids linked by peptide bonds.
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Pharmacology & Biology
Receptor
A biological molecule, often a protein, that can respond when a signaling molecule or drug binds to it.
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Pharmacology & Biology
Agonist
A molecule that binds to a receptor and activates signaling through that receptor.
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Pharmacology & Biology
Half-Life
The time required for the amount or concentration of a substance in a defined system to fall to one-half of a reference value.
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Pharmacology & Biology
Pharmacokinetics (PK)
Also: PK
The study of how a drug or compound moves through the body over time, including absorption, distribution, metabolism, and elimination.
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Pharmacology & Biology
Pharmacodynamics (PD)
Also: PD
The study of what a drug or compound does to a biological system, including target engagement and measurable effects.
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Research & Regulation
FDA-Approved
Also: approved, FDA approval
A status indicating that the FDA has approved a specific drug product for one or more labeled uses after reviewing the required evidence and manufacturing information.
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Research & Regulation
Investigational
A compound, product, or use that is being studied and has not received approval for general marketing for that use.
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Research & Regulation
Preclinical
Research conducted before or outside direct therapeutic testing in humans, often including laboratory and animal studies.
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Research & Regulation
Phase 1 Clinical Trial
Also: Phase I, phase one
An early stage of human clinical development that commonly emphasizes safety, tolerability, pharmacokinetics, and dose-ranging information.
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Research & Regulation
Phase 2 Clinical Trial
Also: Phase II, phase two
A stage of human clinical development that commonly explores efficacy signals, dose selection, and continued safety assessment.
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Research & Regulation
Phase 3 Clinical Trial
Also: Phase III, phase three
A later-stage clinical trial designed to provide substantial evidence about efficacy and safety in the intended population and use context.
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Research & Regulation
Randomized Controlled Trial (RCT)
Also: RCT, randomized trial
A study in which participants are assigned by a random process to different intervention or control groups.
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Research & Regulation
Placebo
A control intervention designed to resemble the study treatment without containing the active study intervention being evaluated.
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Built for cross-reference
Each term page links to related definitions and the BACToBasics tools or research pages where the concept actually appears. That keeps the glossary useful as a learning layer rather than an isolated dictionary.
Definitions are not recommendations
A definition can explain what a unit, trial phase, receptor term, or vial concept means without telling a reader what compound to use, what amount to use, or how to prepare a product.
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