Evidence-Based Supplement & Herb Guides

Recurrent Pregnancy Loss Genetic Test: Karyotype, Translocations, and Results

Understand recurrent pregnancy loss genetic testing, including miscarriage-tissue analysis, parental karyotypes, translocations, result meanings, and reproductive options.

Recurrent pregnancy loss genetic testing looks for chromosome findings that can explain why two or more pregnancies have ended and help estimate what may...

Second-Trimester Quad Screen Test: AFP, hCG, Estriol, Inhibin A, and Results

Learn how the second-trimester quad screen uses AFP, hCG, estriol, and inhibin A, what positive and negative results mean, and which follow-up tests may be offered.

The second-trimester quad screen is a maternal blood test that combines four pregnancy-related markers—alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin...

Sex Chromosome Aneuploidy Test: X and Y Chromosome Results

Understand sex chromosome aneuploidy testing for 45,X, XXY, XXX, XYY, and mosaic results, including prenatal screening accuracy, diagnostic confirmation, and clinical meaning.

A sex chromosome aneuploidy test looks for an unexpected number of X or Y chromosomes. Depending on the setting, it may be a prenatal...

Turner Syndrome Genetic Test: Monosomy X Screening, Diagnosis, and Results

Learn how Turner syndrome testing detects 45,X, mosaic, and structural X results, why cfDNA screening needs confirmation, and what diagnosis means before and after birth.

Turner syndrome genetic testing determines whether cells contain complete or partial loss of one sex chromosome in a person with a female phenotype. The...

Y-Chromosome Microdeletion Test: Male Infertility, AZF Regions, and Results

Understand Y-chromosome microdeletion testing for male infertility, including AZFa, AZFb, and AZFc results, sperm retrieval prognosis, ICSI inheritance, and next steps.

A Y-chromosome microdeletion test looks for missing DNA in the azoospermia factor, or AZF, regions of the Y chromosome. These regions contain genes needed...

Anticonvulsant Pharmacogenetic Test: HLA, CYP2C9, CYP2C19, and Results

Learn how HLA, CYP2C9, and CYP2C19 anticonvulsant pharmacogenetic test results may affect carbamazepine, phenytoin, clobazam, skin-reaction risk, dosing, and follow-up.

An anticonvulsant pharmacogenetic test looks for inherited variants that can affect the safety or handling of certain antiseizure medicines. The most clinically established findings...

BCHE Genetic Test: Pseudocholinesterase Deficiency, Anesthesia Risk, and Results

Understand how a BCHE genetic test, pseudocholinesterase activity, and dibucaine number reveal prolonged succinylcholine or mivacurium paralysis risk and guide safer anesthesia.

A BCHE genetic test looks for inherited changes that reduce the activity of butyrylcholinesterase, an enzyme also called pseudocholinesterase or plasma cholinesterase. Low or...

CACNA1S Genetic Test: Malignant Hyperthermia Risk and Results

Understand what CACNA1S genetic test results mean for malignant hyperthermia risk, trigger-free anesthesia, contracture testing, and family screening.

A CACNA1S genetic test looks for variants in a skeletal-muscle calcium-channel gene that can contribute to malignant hyperthermia susceptibility. Malignant hyperthermia is not an...

Chemotherapy Pharmacogenetic Test: DPYD, UGT1A1, TPMT, and Results

Learn how DPYD, UGT1A1, TPMT, and NUDT15 results can guide fluoropyrimidine, irinotecan, and thiopurine dosing and toxicity prevention.

A chemotherapy pharmacogenetic test can identify inherited differences that affect how a patient handles particular anticancer drugs, but no single result predicts response to...

COMT Genetic Test: Dopamine Metabolism, Pain, Medication Response, and Results

Understand COMT Val158Met results, dopamine metabolism, pain research, medication-response evidence, and why most COMT claims are not clinically actionable.

A COMT genetic test usually examines rs4680, also called Val158Met, a common variant that changes the activity of catechol-O-methyltransferase. This enzyme helps inactivate dopamine,...

CYP1A2 Genetic Test: Caffeine, Clozapine, Drug Metabolism, and Results

Understand CYP1A2 genetic test results for caffeine and clozapine, including why smoking, inflammation, interactions, and drug levels often matter more.

A CYP1A2 genetic test examines variants in an enzyme that metabolizes caffeine and several medicines, including clozapine, olanzapine, theophylline, tizanidine, and duloxetine. Commercial reports...

CYP2B6 Genetic Test: Efavirenz, Methadone, Bupropion, and Results

Understand CYP2B6 test results for efavirenz, methadone, and bupropion, including metabolizer phenotypes, drug-specific guidance, and test limitations.

A CYP2B6 genetic test estimates inherited differences in an enzyme that metabolizes efavirenz, methadone, bupropion, and several other drugs. The result can be clinically...

CYP2C9 Genetic Test: Warfarin, NSAIDs, Phenytoin, and Results

Learn how CYP2C9 test results affect warfarin, NSAIDs, and phenytoin, including metabolizer types, dose guidance, allele coverage, monitoring, and safety limits.

A CYP2C9 genetic test predicts how efficiently the CYP2C9 enzyme clears several medicines, including warfarin, selected nonsteroidal anti-inflammatory drugs, and phenytoin. Reduced-function variants can...

CYP2C19 Clopidogrel Genetic Test: Plavix Response, Heart Risk, and Results

Understand CYP2C19 clopidogrel test results, loss-of-function alleles, Plavix response, alternatives after PCI, and cardiovascular risk implications.

A CYP2C19 clopidogrel genetic test estimates whether a patient can efficiently convert Plavix into its active antiplatelet metabolite. Clopidogrel is a prodrug, so inherited...

CYP2C19 Genetic Test: Clopidogrel, Antidepressants, PPIs, and Results

Understand CYP2C19 test results for clopidogrel, antidepressants, and PPIs, including metabolizer types, dosing implications, interactions, and limitations.

A CYP2C19 genetic test estimates how actively your body makes the CYP2C19 enzyme, which helps process several widely used medicines. The same result can...

CYP2D6 and CYP2C19 Antidepressant Pharmacogenetic Test: SSRI Response and Results

Understand CYP2D6 and CYP2C19 antidepressant test results, SSRI dosing implications, poor and rapid metabolizer findings, interactions, limits, and follow-up.

A CYP2D6 and CYP2C19 antidepressant pharmacogenetic test estimates how quickly a person may process selected antidepressants. It can help explain unusually high exposure, early...

CYP2D6 Genetic Test: Drug Metabolism, Poor Metabolizer, and Results

Understand CYP2D6 genetic test results, poor and ultrarapid metabolizer meanings, copy-number issues, drug effects, phenoconversion, and safe clinical use.

A CYP2D6 genetic test predicts how much functional CYP2D6 enzyme a person is likely to produce. This enzyme affects many antidepressants, opioids, antipsychotics, attention-deficit...

CYP2D6 Opioid Pharmacogenetic Test: Codeine, Tramadol, Oxycodone, and Results

Understand CYP2D6 opioid test results for codeine, tramadol, and oxycodone, including poor and ultrarapid metabolism, interactions, safety, and limits.

A CYP2D6 opioid pharmacogenetic test predicts how efficiently the body converts certain opioids into more active metabolites. The result is most clinically useful for...

CYP3A4 Genetic Test: Drug Metabolism, Variants, and Results

Learn what a CYP3A4 genetic test shows, how CYP3A4*22 affects drug metabolism, which medicines may be influenced, and how to interpret results safely.

A CYP3A4 genetic test looks for inherited variants that may change the activity of CYP3A4, a liver and intestinal enzyme involved in processing many...

CYP3A5 Genetic Test: Tacrolimus Dosing, Metabolism, and Results

Understand CYP3A5 genetic test results, tacrolimus expresser status, genotype-guided starting doses, trough monitoring, and safe transplant medication use.

A CYP3A5 genetic test predicts how strongly a person expresses the CYP3A5 enzyme, one of the main pathways that clears tacrolimus. People who express...