Section
Glossary
118 plain-language definitions of the genetic, medication and mental-health terms used on this site, from agonist to VNTR.
A
- ADHDMental Health Conditions
- Attention-Deficit/Hyperactivity Disorder. A condition that can affect attention, organization, impulse control, motivation and activity levels.
- Adjunctive TreatmentMedication Terms
- A medication added to another treatment to improve the overall response.
- AgonistGeneral Terms
- A medication or chemical that turns on or activates a receptor.
- AlleleGeneral Terms
- A version of a gene. People can inherit different versions of the same gene from their parents.
- AmygdalaGeneral Terms
- A part of the brain involved in fear, anxiety, emotional reactions and detecting possible danger.
- AntidepressantGeneral Terms
- A medication used mainly to treat depression and anxiety. Different antidepressants work on different brain chemical systems.
- AntipsychoticGeneral Terms
- A medication used to treat conditions such as schizophrenia, psychosis and bipolar disorder. Some are also used with antidepressants.
- AnxietyMental Health Conditions
- A state of excessive worry, fear or tension. Anxiety can involve both emotional symptoms and physical symptoms such as a racing heart or restlessness.
- AugmentationMedication Terms
- Adding another medication to improve the effect of the original medication.
B
- Bipolar I DisorderMental Health Conditions
- A form of bipolar disorder that includes at least one episode of mania, which can involve very high energy, reduced need for sleep, rapid thinking and major changes in judgment or behaviour.
- Bipolar II DisorderMental Health Conditions
- A form of bipolar disorder involving periods of hypomania and major depressive episodes. Hypomania is less severe than full mania.
- Blood-Brain Barrier (BBB)General Terms
- A protective barrier that controls which substances can move from the blood into the brain. Some medications cross it more easily than others.
- Brain ChemicalGeneral Terms
- A simple term for chemicals used by brain cells to communicate. Many are called neurotransmitters.
- Brain CircuitGeneral Terms
- A group of connected brain areas that work together to perform a function such as attention, reward, fear or emotional control.
C
- ChemoToxOther Terms
- A genetic report that helps identify whether a person may have an increased inherited risk of certain serious side effects from specific chemotherapy drugs. It is designed to support treatment planning and monitoring and does not replace an oncologist’s clinical judgment.
- ChromosomeGenetic Terms
- A package of DNA inside our cells. Humans normally receive chromosomes from both parents.
- CNSGeneral Terms
- Central Nervous System. The brain and spinal cord.
- CYP EnzymesGeneral Terms
- Liver enzymes that help break down many medications. Genes can affect how active these enzymes are.
- CYP1A2General Terms
- An enzyme involved in processing medications such as clozapine and olanzapine. Smoking and some medications can strongly affect its activity.
- CYP2B6General Terms
- An enzyme that helps process medications including bupropion and, to some extent, sertraline.
- CYP2C19General Terms
- An enzyme that helps process several antidepressants, including citalopram, escitalopram and sertraline.
- CYP2D6General Terms
- An important enzyme that processes many antidepressants, antipsychotics and ADHD medications.
- CYP3A4 / CYP3A5General Terms
- Enzymes that process many medications. Their activity can also be affected by other drugs, foods and supplements.
D
- DepressionMental Health Conditions
- A condition that can affect mood, motivation, energy, sleep, concentration, pleasure and everyday functioning.
- DNAGeneral Terms
- The biological information that contains the instructions used to build and regulate the body.
- DopamineGeneral Terms
- A brain chemical involved in motivation, reward, pleasure, attention and movement.
- Dopamine DysregulationGeneral Terms
- Dopamine signaling that is not working normally. It may be too strong in some brain areas and too weak in others.
- DoseGeneral Terms
- The amount of medication a person takes.
- Drug CompatibilityGeneral Terms
- How well a medication may fit a person's biology. Genetics can provide useful information, but no genetic test can guarantee that a medication will work.
- Drug ExposureMedication Terms
- The amount of medication the body is exposed to over time.
- Drug InteractionGeneral Terms
- When one medication, food, supplement or substance changes how another medication works.
E
- EnzymeGeneral Terms
- A protein that helps the body perform chemical processes, including breaking down medications.
- Executive FunctionGeneral Terms
- Mental skills used for planning, organizing, focusing, controlling impulses and completing tasks.
G
- GABAGeneral Terms
- One of the brain's main calming chemicals. It helps prevent brain circuits from becoming overly active.
- GeneGeneral Terms
- A section of DNA containing instructions that help the body make or regulate proteins.
- Generalized Anxiety DisorderMental Health Conditions
- Ongoing and difficult-to-control worry about many areas of everyday life.
- Genetic PanelGenetic Terms
- A test that examines a group of genes selected for a particular purpose.
- Genetic TestGenetic Terms
- A test that looks at specific parts of a person's DNA.
- Genetic VariationGeneral Terms
- A small natural difference in DNA between people. Some variations can influence medication response.
- GenotypeGeneral Terms
- The specific genetic versions a person has inherited.
- Genotype–Phenotype ComparisonOther Terms
- Comparing a person's genetic information with their current symptoms or observable characteristics to look for areas of agreement or difference.
- GlutamateGeneral Terms
- The brain's main activating chemical. It is important for learning, memory and communication between brain cells.
H
- Half-LifeMedication Terms
- Approximately how long it takes for the amount of a medication in the body to decrease by half.
- HippocampusGeneral Terms
- A brain area involved in memory, learning and the response to stress.
- HTR1AGeneral Terms
- A gene involved in making one type of serotonin receptor. Researchers are studying how differences in this gene may influence medication response.
- HTR2AGeneral Terms
- A gene involved in making a serotonin receptor that is targeted by several psychiatric medications.
- HTR2CGeneral Terms
- A gene involved in serotonin signaling and the regulation of dopamine and other brain systems.
- HyperarousalGeneral Terms
- A state in which the brain and body remain highly alert, tense or ready for danger.
- HypervigilanceGeneral Terms
- Constantly watching or listening for possible danger, even when there may be no immediate threat.
I
- InheritedGenetic Terms
- Passed from parent to child through DNA.
- Intermediate MetabolizerGeneral Terms
- Someone whose body processes certain medications somewhat more slowly than expected because of their genetics.
- IntraMindOther Terms
- PPI's assessment that combines information about symptoms and genetics to help describe patterns related to brain function and neurotransmitter systems.
M
- Major Depressive Disorder (MDD)Mental Health Conditions
- Depression that significantly affects mood, motivation, energy, thinking and everyday functioning.
- MAOIGeneral Terms
- Monoamine Oxidase Inhibitor. An older class of antidepressants that increases serotonin, dopamine and norepinephrine by reducing their breakdown.
- Medication MetabolismGeneral Terms
- The process by which the body breaks down and removes a medication.
- Medication SuitabilityOther Terms
- An assessment of whether a medication appears more or less appropriate for an individual based on available clinical, genetic and medication information. It does not guarantee response.
- Metabolizer StatusGeneral Terms
- A description of how quickly a person's body is expected to process a medication through a particular enzyme.
- MonoaminesGeneral Terms
- A group of brain chemicals that includes serotonin, dopamine and norepinephrine.
- Mood StabilizerGeneral Terms
- A medication used to help control large changes in mood, especially in bipolar disorder. Lithium is one example.
N
- NDRIGeneral Terms
- Norepinephrine-Dopamine Reuptake Inhibitor. A medication that increases norepinephrine and dopamine signaling. Bupropion is an example.
- NeuroMapOther Terms
- A symptom-based assessment that helps describe patterns in how serotonin, dopamine and norepinephrine systems may be functioning in different parts of the brain. It does not directly measure neurotransmitter levels.
- NeuroplasticityGeneral Terms
- The brain's ability to adapt, reorganize and strengthen or weaken connections over time.
- NeurotoneGeneral Terms
- A term used by Personalized Prescribing to describe the overall functional pattern of a neurotransmitter system, rather than simply calling it “high” or “low.”
- NeurotransmitterGeneral Terms
- A chemical messenger used by brain cells to communicate with one another.
- Neurotransmitter PatternOther Terms
- A description of how symptoms may suggest that certain brain systems are functioning differently. It is not a direct measurement of neurotransmitter levels in the brain.
- NorepinephrineGeneral Terms
- A brain chemical involved in energy, alertness, attention, concentration and the stress response.
- Norepinephrine DysregulationGeneral Terms
- Norepinephrine activity that is not properly balanced. It may be too low in attention-related brain areas and too strong in stress-related areas.
- Normal MetabolizerGeneral Terms
- Someone whose body is expected to process a medication at the usual rate through a particular enzyme.
O
- Obsessive-Compulsive Disorder (OCD)Mental Health Conditions
- A condition involving unwanted repetitive thoughts or urges and behaviours or mental actions performed to reduce distress.
- Opti-MedOther Terms
- PPI's pharmacokinetic-focused pharmacogenomic test that examines how genetic differences may affect medication metabolism.
P
- Panic DisorderMental Health Conditions
- Repeated episodes of sudden intense fear or panic, sometimes accompanied by racing heart, shortness of breath or dizziness.
- Partial AgonistGeneral Terms
- A medication that activates a receptor, but less strongly than a full agonist.
- Pharmacodynamic GenesGeneral Terms
- Genes that may influence how the brain or body responds to a medication after the medication reaches its target.
- Pharmacodynamics (PD)General Terms
- What a medication does to the brain and body. It includes how the medication interacts with receptors, transporters and other biological systems.
- Pharmacogenomics (PGx)General Terms
- The study of how a person's genes can influence their response to medications.
- Pharmacokinetic GenesGeneral Terms
- Genes that influence how quickly the body processes or removes medications.
- Pharmacokinetics (PK)General Terms
- What the body does to a medication, including how it is absorbed, processed and removed.
- PhenoconversionGeneral Terms
- When a person's actual ability to process a medication change because of another medication or environmental factor, even though their genes have not changed.
- PhenotypeGeneral Terms
- An observable characteristic. In pharmacogenomics, it can describe how active an enzyme is expected to be, such as poor or normal metabolizer.
- PolygenicGeneral Terms
- Involving many genes rather than just one gene. Medication response is often polygenic because many biological systems work together.
- Polygenic ApproachGeneral Terms
- Looking at several relevant genes together to understand a medication pathway rather than expecting one gene to predict the entire response.
- Poor MetabolizerGeneral Terms
- Someone whose body has very little activity from a particular medication-processing enzyme. Some medications may therefore remain in the body longer.
- Post-Traumatic Stress Disorder (PTSD)Mental Health Conditions
- A condition that can develop after trauma when fear, memory and stress systems remain highly sensitive after the danger has passed.
- Prefrontal Cortex (PFC)General Terms
- A brain area important for attention, planning, decision-making, emotional control and impulse control.
- PsychosisGeneral Terms
- A condition in which a person may have difficulty distinguishing what is real from what is not. It can include hallucinations or delusions.
R
- Rapid MetabolizerGeneral Terms
- Someone whose body processes certain medications faster than usual through a particular enzyme.
- ReceptorGeneral Terms
- A structure on or inside a cell that receives chemical messages. Medications often work by activating or blocking receptors.
- RemissionMedication Terms
- When symptoms have improved enough that they are minimal or no longer significantly interfere with everyday life.
- ReuptakeGeneral Terms
- The process by which a brain chemical is taken back into the nerve cell after it has been released.
- Reward SystemGeneral Terms
- Brain circuits that help create motivation, pleasure and the desire to repeat rewarding activities. Dopamine plays an important role.
- RxReportOther Terms
- PPI's pharmacogenomic assessment designed to help healthcare professionals understand how a person's genetics may influence psychiatric medication use.
S
- SchizophreniaMental Health Conditions
- A mental health condition that can affect thinking, perception, motivation, emotions and the ability to distinguish internal thoughts from outside events.
- SerotoninGeneral Terms
- A brain chemical involved in mood, anxiety, emotional control, sleep and repetitive thinking.
- Serotonin DysregulationGeneral Terms
- Serotonin signaling that is not functioning normally in particular brain circuits. This is more accurate than simply saying someone has “low serotonin.”
- Serotonin TransporterGeneral Terms
- A protein that moves serotonin back into nerve cells after it has been released. SSRIs block this transporter.
- Side EffectMedication Terms
- An unwanted effect that can occur while taking a medication.
- SLC6A2General Terms
- The gene that helps make the norepinephrine transporter.
- SLC6A3General Terms
- The gene that helps make the dopamine transporter.
- SLC6A4General Terms
- The gene that helps make the serotonin transporter. Genetic differences in this gene have been studied for their possible influence on antidepressant response.
- SNPGenetic Terms
- Pronounced “snip.” A small difference at one position in DNA that is common among people.
- SNRIGeneral Terms
- Serotonin-Norepinephrine Reuptake Inhibitor. An antidepressant that increases signaling through both serotonin and norepinephrine systems.
- Social Anxiety DisorderMental Health Conditions
- Strong fear or anxiety about social situations or being judged by others.
- SSRIGeneral Terms
- Selective Serotonin Reuptake Inhibitor. A common antidepressant that increases serotonin signaling by blocking the serotonin transporter.
- StimulantGeneral Terms
- A medication that increases activity in dopamine and norepinephrine systems. Stimulants are commonly used to treat ADHD.
- StriatumGeneral Terms
- A brain area involved in reward, motivation, habits, movement and deciding which actions are important.
- Symptom AssessmentOther Terms
- A structured set of questions used to understand a person's current symptoms and how different brain systems may be functioning.
- SynapseGeneral Terms
- The tiny space between two nerve cells where chemical messages are passed.
T
- TaperingMedication Terms
- Gradually reducing a medication rather than stopping it suddenly.
- TCAGeneral Terms
- Tricyclic Antidepressant. An older class of antidepressants that mainly affects serotonin and norepinephrine.
- Therapeutic Drug Monitoring (TDM)General Terms
- Measuring the amount of a medication in the blood to help determine whether the level is too low, appropriate or too high.
- Therapeutic EffectMedication Terms
- The intended beneficial effect of a medication.
- TransporterGeneral Terms
- A protein that moves neurotransmitters or other substances from one place to another. Many psychiatric medications work by blocking transporters.
- Treatment Resistant DepressionGeneral Terms
- Depression that has not improved enough after appropriate treatment with more than one antidepressant.
- Treatment ResponseMedication Terms
- How much a person's symptoms improve after treatment.
U
- Ultrarapid MetabolizerGeneral Terms
- Someone whose body processes certain medications much faster than usual because of highly active medication-processing enzymes.
V
W
- Working MemoryGeneral Terms
- The brain's ability to temporarily hold and use information, such as remembering instructions while completing a task.