Peptide Glossary
62+ plain-language definitions covering everything from basic peptide chemistry and receptor mechanisms to reconstitution, testing methodology, and regulatory terminology.
The Building Blocks
Amino Acid
The basic building block of peptides and proteins.
Amino acids are small organic molecules that link together to form peptides and proteins. Each contains an amino group, a carboxyl group, and a side chain that gives it distinct chemical properties.
There are 20 standard amino acids that occur in nature, and the specific combination and order used in a chain determines the resulting peptide's structure and behavior.
Peptide Bond
The chemical link that joins amino acids together in a chain.
A peptide bond forms when the carboxyl group of one amino acid reacts with the amino group of another, releasing a water molecule and creating a covalent link between the two.
A chain of amino acids connected by repeated peptide bonds is what defines a peptide or protein structurally, regardless of length.
Peptide
A relatively short chain of amino acids, commonly described as containing roughly 2-50 amino-acid units.
A peptide is a chain of amino acids joined by peptide bonds. The term generally covers chains ranging from just two amino acids up to roughly 50, though the exact cutoff between a peptide and a small protein is not fixed in the scientific literature.
Peptides occur naturally in the body as hormones, signaling molecules, and enzyme fragments, and many research peptides are designed as analogs of these naturally occurring sequences.
Protein
A longer amino-acid chain that folds into a specific three-dimensional structure.
Proteins and peptides belong to the same general family โ both are chains of amino acids linked by peptide bonds โ but proteins are typically much larger and fold into complex, stable three-dimensional shapes that determine their function.
Where a short peptide might act mainly through its sequence and a simple structure, a protein's biological role usually depends heavily on that folded 3D shape.
Residue
A single amino-acid unit within a peptide or protein chain.
Once an amino acid is incorporated into a chain via peptide bonds, it's referred to as a "residue" rather than a free amino acid, since it has lost a water molecule in the bonding process.
A peptide's length is often described by its residue count โ for example, a "31-residue peptide" simply means a chain of 31 linked amino acids.
Sequence
The specific order of amino acids in a peptide.
A peptide's sequence is the ordered list of its amino acid residues, typically written using standard one- or three-letter codes from the N-terminus (start) to the C-terminus (end) of the chain.
Even small changes to a sequence โ substituting, adding, or removing a single residue โ can significantly change a peptide's stability, receptor binding, or half-life, which is the basis for most peptide analogs.
Oligopeptide
A peptide made from a relatively small number of amino acids.
"Oligopeptide" is a general term for peptides built from a small number of residues, generally cited as somewhere under 10-20, though usage varies across the literature.
It sits at the short end of the peptide size spectrum, distinct from longer oligopeptides and polypeptides that contain many more residues.
Polypeptide
A longer chain containing many amino acids.
A polypeptide is a single chain built from many amino acid residues linked by peptide bonds โ structurally the same chemistry as a short peptide, just longer.
The line between a "large peptide" and a "small polypeptide" or protein isn't strictly defined; in practice the terms overlap depending on the source and field.
Analog
A modified version of a naturally occurring molecule, often designed to change its stability, potency, selectivity, or duration of action.
An analog keeps the core structure or activity of a parent molecule but includes deliberate modifications โ substituted residues, added groups, or structural tweaks โ intended to change how it behaves.
Many research peptides are analogs of naturally occurring hormones. CJC-1295, for example, is described as an analog of growth-hormone-releasing hormone (GHRH) engineered for a longer duration of action than the native hormone.
Mechanisms of Action
Receptor
A cellular target โ often compared to a "lock" โ that a signaling molecule can bind to.
A receptor is a protein, usually on or in a cell, that a specific signaling molecule (the "key") can bind to, triggering a downstream cellular response.
Most peptide hormones and their analogs act by binding to one or more specific receptor types, which is why understanding a compound's receptor target is central to understanding what it does.
Agonist
A substance that activates a receptor and turns on its signaling pathway.
An agonist binds to a receptor in a way that triggers the same downstream signaling that the receptor's natural ligand would produce.
Agonists can vary in strength (potency) and in how completely they activate a receptor relative to the natural ligand (efficacy) โ terms often summarized as full, partial, or biased agonism.
Antagonist
A substance that blocks a receptor and prevents or reduces its activation.
An antagonist binds to a receptor without activating it, and in doing so can physically block the receptor's natural ligand โ or an agonist โ from binding and producing an effect.
Antagonists are the functional opposite of agonists, and the two terms are used together throughout receptor pharmacology to describe how a compound interacts with its target.
GPCR (G-Protein-Coupled Receptor)
A large and common family of receptors involved in cellular signaling.
GPCRs are a large family of cell-surface receptors that, once activated, trigger an internal signaling cascade via associated G-proteins. They're involved in an enormous range of physiological processes.
Many peptide hormones โ including ghrelin, GLP-1, and GHRH โ act through GPCRs, which is why the term shows up so often in descriptions of how peptide analogs work.
Selective / Selectivity
How narrowly a compound acts on one target rather than several.
Selectivity describes how specifically a compound engages its intended receptor versus binding to related or unrelated targets it wasn't designed for.
Greater selectivity may reduce certain off-target effects associated with hitting unintended receptors, though it does not automatically guarantee safety โ selectivity is one factor among many.
Secretagogue
A substance that stimulates the secretion of another substance, such as a hormone.
A secretagogue triggers a cell or gland to release (secrete) a substance it produces โ most commonly used in peptide research to describe compounds that stimulate hormone release.
Growth hormone secretagogues, for instance, are compounds that prompt the pituitary gland to release growth hormone, whether by mimicking GHRH, acting through the ghrelin receptor, or another mechanism.
GHRH Analog
A compound that mimics growth-hormone-releasing hormone and can stimulate growth hormone release.
A GHRH analog is a modified version of growth-hormone-releasing hormone designed to activate the same receptor as the natural hormone, often with improved stability or a longer duration of action.
Sermorelin and certain forms of CJC-1295 are commonly discussed examples of GHRH analogs in the research peptide space.
GHRP (Growth Hormone-Releasing Peptide)
A compound that stimulates growth hormone release through the ghrelin receptor.
GHRPs are a class of peptides that act as agonists at the ghrelin receptor, which โ among other effects โ stimulates the release of growth hormone from the pituitary gland.
Ipamorelin is one commonly cited example, often discussed in research contexts alongside GHRH analogs like CJC-1295 due to their complementary mechanisms.
Ghrelin Mimetic
A compound that mimics some of the biological actions of ghrelin, generally by activating the ghrelin receptor.
Ghrelin is a naturally occurring hormone involved in appetite regulation and growth hormone release. A ghrelin mimetic is a compound designed to reproduce some of its effects by acting on the same receptor.
GHRPs are one category of ghrelin mimetic; some non-peptide compounds are also studied for this same mechanism.
GLP-1 Receptor Agonist
A compound that activates the GLP-1 receptor and influences functions such as appetite, glucose regulation, and insulin secretion.
GLP-1 (glucagon-like peptide-1) is a naturally occurring incretin hormone. A GLP-1 receptor agonist binds to and activates the same receptor, influencing appetite signaling, gastric emptying, and glucose-dependent insulin secretion.
Semaglutide is one widely known example, and it's frequently compared against dual and triple agonists like tirzepatide and retatrutide that act on more than one receptor.
Peptidomimetic
A molecule designed to mimic a peptide's structure or biological activity without necessarily being a conventional peptide.
A peptidomimetic reproduces the receptor-binding behavior of a peptide using a molecular scaffold that isn't a standard amino acid chain โ which can change how it's absorbed, metabolized, or administered.
MK-677 is commonly discussed as a non-peptide, orally active ghrelin-receptor agonist, illustrating how a peptidomimetic can act on the same target as a peptide while behaving very differently in the body.
Pharmacokinetics
Pharmacokinetics
The study of how a substance is absorbed, distributed, metabolized, and eliminated by the body.
Pharmacokinetics (often abbreviated PK) covers the full journey of a compound through the body โ how it's absorbed after administration, how it distributes into tissues, how it's broken down, and how it's ultimately cleared.
For peptides, pharmacokinetics is especially important because most are broken down quickly by enzymes in the blood and tissues, which is why route of administration and half-life are recurring themes in peptide research.
Bioavailability
The fraction of an administered dose that reaches systemic circulation.
Bioavailability is expressed as a percentage of the administered amount that actually makes it into the bloodstream in active form, versus being broken down or excreted before it can act.
Route of administration has a major effect on bioavailability โ peptides given orally typically have very low bioavailability due to digestive breakdown, which is a large part of why most are studied via injection instead.
First-Pass Metabolism
The breakdown of a substance โ primarily in the intestinal wall and liver โ before it reaches systemic circulation.
When a substance is taken orally, it passes through the intestinal wall and liver before reaching general circulation, and both organs can metabolize a significant portion of it before it ever has a chance to act.
This is especially relevant to peptides, most of which are also vulnerable to being broken down by digestive enzymes โ a combination that makes oral peptide delivery a persistent formulation challenge.
Peptidase
An enzyme that breaks peptide bonds.
Peptidases (also called proteases) are enzymes present throughout the body โ in blood, the digestive tract, and tissues โ that cleave the peptide bonds holding an amino acid chain together.
Peptidases are one of the main reasons many natural peptides have very short half-lives, and a major driver behind why analogs are engineered with modified sequences or protective structural changes.
DAC (Drug Affinity Complex)
A modification designed to promote binding to proteins in the blood, potentially extending a compound's half-life.
DAC is a chemical modification attached to a peptide that promotes reversible binding to albumin, a plasma protein. Because albumin has a long half-life of its own, binding to it can slow a peptide's clearance from the body.
CJC-1295 is commonly discussed both with and without DAC โ the DAC version is associated with a substantially longer duration of action than the non-DAC form.
Pulsatile vs. Sustained Signaling
A signal delivered in intermittent bursts compared with one maintained at a relatively continuous level.
Pulsatile signaling refers to a hormone or compound being released or administered in distinct bursts, followed by a return closer to baseline โ the pattern in which the body naturally releases many hormones.
Sustained signaling instead keeps levels relatively elevated and steady over time. Whether a research compound produces a more pulsatile or more sustained profile depends heavily on its half-life and dosing frequency, and is a common point of comparison between short-acting and long-acting analogs of the same hormone.
Form, Handling & Administration
Lyophilized Powder
Freeze-dried peptide with the water content removed, used for long-term stability during storage and shipping.
Lyophilization (freeze-drying) removes water from a peptide solution under vacuum at low temperature, leaving a stable powder. Peptides in this form resist degradation far better than peptides already in solution, which is why virtually all research peptides are sold lyophilized rather than pre-mixed.
A lyophilized peptide is stable at refrigerated or frozen temperatures for extended periods. Once reconstituted into solution, that stability window shortens considerably โ which is why unreconstituted vials and reconstituted vials have different storage guidance.
Reconstitution
The process of dissolving lyophilized (freeze-dried) peptide powder into a liquid solution before use.
Peptides typically ship as a lyophilized powder for stability. Reconstitution is the process of adding a solvent โ most often bacteriostatic water โ to bring the peptide back into solution at a known concentration (mg/mL), so it can be measured and drawn accurately with a syringe.
The volume of solvent added determines the final concentration: a 5mg vial reconstituted with 1mL of water yields a 5mg/mL solution, while the same vial reconstituted with 2mL yields 2.5mg/mL. Getting this number right is the basis of every dosing calculation.
Bacteriostatic Water (BAC Water)
Sterile water containing 0.9% benzyl alcohol, used to reconstitute lyophilized peptide powder.
Bacteriostatic water is sterile water for injection that contains 0.9% benzyl alcohol as a preservative. The benzyl alcohol inhibits bacterial growth, which is why bacteriostatic water can be used to reconstitute a vial and then drawn from multiple times over a period of weeks, unlike plain sterile water which is meant for single use.
It's added slowly to a lyophilized peptide vial โ usually run down the inside wall of the vial rather than injected directly onto the powder โ to avoid excess foaming or agitation that can degrade the peptide structure.
Sterile Water
Water prepared to be sterile but containing no antimicrobial preservative.
Sterile water for injection is free of microbial contamination but, unlike bacteriostatic water, contains no preservative to inhibit bacterial growth once a vial has been opened.
Because it offers no ongoing antimicrobial protection, sterile water is generally treated as single-use once a vial is punctured, and is not automatically interchangeable with bacteriostatic water in a reconstitution protocol.
Subcutaneous (SC) vs Intramuscular (IM) Injection
Two injection routes โ SC deposits into the fat layer under the skin, IM deposits into muscle tissue โ with different absorption profiles.
Subcutaneous (SC) injection deposits solution into the layer of fat just beneath the skin, typically using a short, fine-gauge needle (commonly the same insulin syringe used for reconstituted peptide dosing). Absorption from SC tissue is generally slower and more gradual than IM.
Intramuscular (IM) injection deposits solution directly into muscle tissue, which has a richer blood supply and can lead to faster absorption for some compounds. Most peptide research protocols specify SC administration by default; IM is used where a specific protocol calls for it.
IV (Intravenous)
Administration directly into a vein.
Intravenous administration delivers a substance straight into venous circulation, producing the fastest onset of any common route since it bypasses absorption entirely.
This is a higher-risk route generally associated with clinical care, requiring sterile technique and, typically, direct medical supervision โ it is not a standard route used in peptide self-research protocols.
Intranasal
Administered through the nose.
Intranasal administration delivers a compound via the nasal mucosa, which is richly vascularized and allows some molecules to be absorbed without passing through the digestive tract.
This route is used for certain approved medications and has been studied for select peptides in the research literature, though absorption and bioavailability vary widely by compound.
Cold Chain / Storage Temperature
The temperature-controlled handling a peptide needs from shipping through storage, to prevent degradation.
Peptides are proteins, and like most proteins, their structure can degrade with heat exposure, agitation, or time in solution. "Cold chain" refers to keeping a product within its required temperature range continuously โ during shipping, and then in storage once it arrives.
As a general pattern: unreconstituted lyophilized powder is more heat-stable and can typically tolerate brief transit at room temperature, while long-term storage calls for freezer temperatures (commonly -20ยฐC). Once reconstituted into solution, refrigeration (2-8ยฐC) and prompt use become far more important, and repeated freeze-thaw cycles should be avoided.
Units & Measurement
mg (Milligram)
A unit of mass equal to one-thousandth of a gram.
The milligram is the standard unit used on peptide vial labels and Certificates of Analysis to describe the total mass of peptide contained.
It's distinct from concentration (mg/mL), which describes how that total mass is distributed once the vial has been reconstituted into a specific volume of liquid.
mcg / ฮผg (Microgram)
A unit of mass equal to one-millionth of a gram. One milligram equals 1,000 micrograms.
Micrograms (written as mcg or ฮผg) are used when the relevant amounts are far smaller than a milligram โ common for potent peptides that are effective at very low doses.
Because 1 mg = 1,000 mcg, a mismatch between these units is one of the most common sources of dosing calculation errors, which is why unit conversion is a core function of any peptide dosing calculator.
IU (International Unit)
A measure of biological activity rather than a universal measure of mass.
An International Unit standardizes a substance's biological potency rather than its physical mass, which is why IU is used for certain hormones and biologics instead of milligrams.
The conversion between IU and mass is specific to each substance โ there is no universal IU-to-mg formula, so any conversion has to reference that particular compound's established standard.
Concentration
The amount of a substance contained in a given volume of solution, commonly expressed as amount per unit of volume.
Concentration, typically expressed as mg/mL, describes how much peptide is present in each unit of liquid volume after reconstitution โ the figure that translates a vial's total mg content into something measurable with a syringe.
Concentration is a function of both the total peptide mass and the volume of solvent added during reconstitution, so changing either one changes the resulting concentration.
Quality & Testing
HPLC-MS Testing
High-Performance Liquid Chromatography paired with Mass Spectrometry โ the analytical method used to verify a peptide's identity and purity.
HPLC (High-Performance Liquid Chromatography) separates a sample into its individual components based on how they interact with a chromatography column, producing a chromatogram that shows purity as the percentage of the total signal belonging to the intended peptide peak.
MS (Mass Spectrometry) measures the molecular weight of separated components, confirming that the primary peak actually is the peptide it's supposed to be, not just a similarly-behaving impurity. Used together, HPLC-MS verifies both identity (is this actually the right compound) and purity (how much of the vial is that compound versus everything else).
Mass Spectrometry
A laboratory technique used to help identify a compound by measuring its mass-to-charge characteristics.
Mass spectrometry ionizes a sample and measures the mass-to-charge ratio of the resulting fragments, producing a molecular weight profile that can confirm a compound's identity.
In peptide testing it's typically paired with HPLC: HPLC separates the sample's components, and mass spectrometry confirms that the dominant peak matches the expected molecular weight of the intended peptide.
Certificate of Analysis (CoA)
The lab report for a specific batch, showing its measured purity and identity test results.
A Certificate of Analysis is a document from an independent testing laboratory reporting the results of specific tests โ typically HPLC purity and mass spec identity confirmation โ for a specific manufacturing batch, referenced by a batch or lot number.
A CoA is batch-specific, not product-generic: it tells you what a lab found in that particular batch, not what the supplier claims about the product in general. Checking that the batch number on your CoA matches the batch number on your vial is the only way to confirm the two actually correspond. A CoA is also only as reliable as the sample, methods, and laboratory behind it.
Purity Percentage
The proportion of a vial's contents that is the intended peptide, as measured by HPLC โ not a measure of safety or effectiveness.
Purity percentage, as reported on a Certificate of Analysis, reflects the proportion of the HPLC chromatogram's total peak area attributable to the intended peptide, versus related impurities, degradation products, or synthesis byproducts.
A 99% purity result means roughly 1% of the measured signal comes from something other than the target peptide โ commonly truncated sequences or oxidation products from the synthesis process. A high reported purity percentage does not automatically confirm sterility, correct dosing, or absence of endotoxins โ purity is an analytical measurement of composition, not a claim about safety or biological effect.
Endotoxin
A potentially harmful bacterial contaminant.
Endotoxins are components of certain bacterial cell walls that can trigger a strong immune or inflammatory response, even in very small amounts, if introduced into the body.
Endotoxin testing is particularly important for products intended for injection, since the injectable route bypasses the natural barriers that would otherwise limit exposure โ it's typically reported separately from HPLC purity, since the two measure entirely different things.
Sterility Testing
Testing intended to determine whether viable contaminating microorganisms are present.
Sterility testing checks a sample for the presence of viable bacteria, fungi, or other microorganisms that could pose a contamination risk.
Like endotoxin testing, it addresses a different question than HPLC purity testing โ a peptide can show a high purity percentage on a chromatogram while still carrying a microbial contamination risk if sterility hasn't been separately verified.
Third-Party Testing
Testing performed by a laboratory that is independent of the seller or manufacturer.
Third-party testing means the lab generating the Certificate of Analysis has no ownership or financial stake in the product being tested, which reduces (though doesn't eliminate) potential conflicts of interest compared to in-house testing.
Verifying that a CoA actually comes from an independent lab โ rather than being self-reported by the seller โ is a common due-diligence step when evaluating a product's documentation.
USP Monograph
An official public standard published by the United States Pharmacopeia for the identity, strength, quality, and purity of a substance or product.
A USP monograph is a formal specification that defines how a substance should be tested and what results qualify it as meeting the pharmacopeial standard for identity, strength, and purity.
Not every research peptide has an established USP monograph, since many are newer or not approved as drugs โ where one does exist, it provides a recognized external benchmark beyond a supplier's own internal specifications.
GMP (Good Manufacturing Practice)
Manufacturing requirements and quality systems intended to ensure that products are consistently produced and controlled.
GMP refers to a set of standards governing facility conditions, process controls, documentation, and quality checks intended to make manufacturing consistent and traceable batch to batch.
A manufacturer's GMP status speaks to how a batch was produced and controlled; it's a separate question from whether that specific batch has since been independently tested and confirmed to meet its stated specifications.
Legal & Regulatory
Research Use Only (RUO)
A labeling designation meaning a compound is sold for laboratory and research purposes, not for human or animal consumption.
"Research Use Only" (RUO) is a standard designation for compounds that have not been evaluated or approved by a regulatory body โ such as Health Canada or the FDA โ for human or veterinary use. RUO products are intended for in vitro or laboratory research settings only.
This designation is distinct from a compound simply lacking approval for a specific indication (many approved drugs are also studied for off-label uses). RUO means the product itself, as sold, has not been evaluated for human consumption, dosing safety, or clinical use of any kind.
Research Chemical
A substance marketed for laboratory research, often labeled "not for human consumption."
"Research chemical" is a common label applied to compounds sold for laboratory study rather than for approved human or veterinary use, frequently paired with explicit "not for human consumption" language.
This label does not, by itself, establish that a product is safe, effective, or suitable for medical use โ it describes the intended sale and use category, not a safety or quality claim.
FDA-Approved
Reviewed and approved by the U.S. Food and Drug Administration as a drug for one or more specific uses.
FDA approval means a drug has gone through a formal review process demonstrating safety and efficacy for at least one specific approved indication, dose, and population.
Most products marketed online as "research peptides" are not FDA-approved for human use โ approval status is specific to a formulation and indication, and does not transfer simply because a related molecule has been approved elsewhere.
Off-Label Use
The use of an approved drug for a condition, population, dose, or route that is not included in its FDA-approved labeling.
Off-label use occurs when an already-approved medication is used outside the specific indication, dosage, population, or route described in its official labeling.
Licensed clinicians may prescribe approved drugs off-label when medically appropriate, based on their professional judgment โ this is a distinct legal and clinical category from a product that has no approval at all.
Compounding
The preparation of a customized medication by a qualified pharmacy or outsourcing facility under applicable laws and quality requirements.
Compounding is the practice of preparing a customized drug formulation โ a different dose, form, or combination โ under regulatory frameworks distinct from standard commercial drug manufacturing.
In the U.S., compounding is carried out primarily by two categories of licensed facility: 503A pharmacies and 503B outsourcing facilities, each operating under its own set of federal and state requirements.
503A Pharmacy
A state-licensed pharmacy that generally compounds medications based on prescriptions for identified individual patients.
A 503A pharmacy is licensed at the state level and typically compounds a specific preparation only in response to a prescription for a named individual patient.
This distinguishes 503A pharmacies from 503B outsourcing facilities, which can compound in larger batches under separate federal oversight.
503B Outsourcing Facility
A facility that may compound certain sterile medications in larger quantities under federal requirements and FDA oversight.
503B outsourcing facilities register with the FDA and operate under federal current Good Manufacturing Practice (cGMP) requirements, which allows them to compound sterile preparations in larger quantities than a typical 503A pharmacy.
This category exists specifically to supply hospitals, clinics, and prescribers with compounded sterile products at scale, under a distinct regulatory framework from both standard drug manufacturers and patient-specific 503A compounding.
Bulks List
An informal name for FDA lists identifying certain bulk drug substances that may be eligible for use in compounding under specified conditions.
The "Bulks List" refers informally to the FDA's published lists of bulk drug substances that 503A pharmacies or 503B outsourcing facilities may use in compounding under defined conditions.
A substance's presence on a Bulks List doesn't equate to full drug approval โ it reflects a determination specifically about its eligibility for use in compounding, evaluated separately under the Category 1 / Category 2 framework.
Category 1 / Category 2
FDA classifications used during the evaluation of certain bulk substances nominated for compounding.
Category 1 generally covers nominated bulk substances that are under evaluation and may qualify for interim enforcement discretion while the FDA's review is ongoing.
Category 2 identifies substances that the FDA has associated with significant safety risks, which weighs against their use in compounding regardless of nomination status.
DSHEA (Dietary Supplement Health and Education Act)
The 1994 U.S. law that established the modern federal framework for dietary supplements.
DSHEA created the current U.S. regulatory category for dietary supplements, setting out how such products are defined, labeled, and overseen separately from conventional drugs.
Calling something a "peptide" does not automatically make it a lawful dietary-supplement ingredient โ whether a given substance qualifies depends on how it's defined and regulated under DSHEA and related FDA guidance, not on the marketing term used to describe it.
WADA Prohibited List
The World Anti-Doping Agency's list of substances and methods prohibited in sport.
The WADA Prohibited List catalogs substances and methods banned in competitive sport under the World Anti-Doping Code, and is updated annually to reflect new compounds and emerging research.
Many peptide hormone analogs and secretagogues discussed in research contexts appear on this list, which is a separate consideration from a substance's legal or regulatory status outside of competitive sport.
Research & Usage Concepts
Cycle
The use of a compound for a defined period, sometimes followed by a break.
A "cycle," as discussed in research and community contexts, refers to a defined period during which a compound is used, sometimes followed by a break before it's used again.
This term describes a structural concept only, not a personal protocol or recommendation โ the length and structure of any cycle discussed in the literature varies enormously by compound and research question.
Stacking
Using more than one compound during the same period.
"Stacking" refers to the concurrent use of multiple compounds within the same period, often chosen because they're thought to act through complementary mechanisms.
CJC-1295 and Ipamorelin, for example, are frequently discussed as a stack because one is a GHRH analog and the other a GHRP acting through a different receptor โ the concept of stacking is discussed here only as a definition, not a recommendation.
Titration
Carefully adjusting an amount over time to reach a particular therapeutic effect or improve tolerability.
Titration describes the process of incrementally adjusting an amount โ usually upward from a lower starting point โ based on observed response, with the goal of finding an effective level while managing tolerability.
It's a general pharmacological concept, not specific to any one compound, and is commonly discussed alongside dose escalation in research protocols for compounds with a defined therapeutic window.
Dose Escalation
Increasing a dose in planned stages.
Dose escalation refers to increasing an amount in a series of planned, discrete steps over time, typically according to a pre-defined schedule.
It's related to titration but not necessarily identical โ titration usually implies adjusting in response to observed effect, while dose escalation can follow a fixed schedule regardless of individual response.
Research use only. Definitions above describe general laboratory and pharmacological concepts for research education purposes. They are not medical advice and do not describe or endorse human use of any product sold by JA Performance.