CYP2C19 Genotyping Test
Short Name: CYP2C19
Also known as: Cytochrome P450 2C19 Genotyping, CYP2C19 Pharmacogenomic Test, Clopidogrel Resistance Test, CYP2C19 Mutation Analysis
CYP2C19 Genotyping Test test available at DNA Labs India for ₹10,500. Uses PCR (Polymerase Chain Reaction), DNA Sequencing on Whole Blood samples. Results in Reports are available within 15 working days from sample receipt at the laboratory. Submit sample by 11 AM Saturday for timely processing.. Free home collection in 300+ cities across India.
🩺 Medically Reviewed By
Dr SULOCHANA HEMCHANDRA HOLLA
Consultant Medical Geneticist · Reg: 8532
Last reviewed: September 7, 2026
Overview
The primary purpose of the CYP2C19 Genotyping Test is to determine a patient's metabolizer status for the CYP2C19 enzyme, enabling healthcare providers to make informed, personalized decisions about drug selection and dosing. This test is particularly valuable for patients who are about to start or are currently taking medications metabolized by the CYP2C19 enzyme. By identifying whether a patient is a normal, intermediate, poor, or rapid metabolizer, physicians can adjust drug choices and dosages to maximize therapeutic benefit while minimizing the risk of adverse drug reactions, treatment failure, or drug toxicity.
- Test Code
- 461
- CPT Code
- 81225
- ICD Code
- Z15.89
- Price
- ₹10,500
- Sample Type
- Whole Blood
- Result Time
- Reports are available within 15 working days from sample receipt at the laboratory. Submit sample by 11 AM Saturday for timely processing.
- Fasting Required
- No
- Method
- PCR (Polymerase Chain Reaction), DNA Sequencing
Sample Collection
Duly filled Genomics Clinical Information Requisition Form (Form 20) is mandatory. Inform your physician about any recent blood transfusions, bone marrow transplants, or current medications. No fasting is required for this test.
Method: Venipuncture
Laboratory Analysis
A trained phlebotomist will collect approximately 4 mL of whole blood via venipuncture into a lavender-top EDTA tube. The procedure typically takes less than 5 minutes.
Report Delivery
Apply gentle pressure to the puncture site with a cotton ball or gauze for 3–5 minutes. A small bruise may form, which is normal. Avoid heavy lifting with the affected arm for the rest of the day.
Timeline: Reports are available within 15 working days from sample receipt at the laboratory. Submit sample by 11 AM Saturday for timely processing.
Patient Instructions
About This Test
Who Should Get This Test
The primary purpose of the CYP2C19 Genotyping Test is to determine a patient's metabolizer status for the CYP2C19 enzyme, enabling healthcare providers to make informed, personalized decisions about drug selection and dosing. This test is particularly valuable for patients who are about to start or are currently taking medications metabolized by the CYP2C19 enzyme. By identifying whether a patient is a normal, intermediate, poor, or rapid metabolizer, physicians can adjust drug choices and dosages to maximize therapeutic benefit while minimizing the risk of adverse drug reactions, treatment failure, or drug toxicity.
How to Prepare
- Duly filled Genomics Clinical Information Requisition Form (Form 20) is mandatory
- Collect 4 mL (2 mL min.) whole blood in 1 Lavender top (EDTA) tube
- Ship the sample refrigerated. DO NOT FREEZE
- Label the sample correctly with patient details and date of collection
- Submit sample by 11 AM Saturday for timely processing
- No fasting or special dietary preparation is required
Doctor's Notes
Reviewed by Dr SULOCHANA HEMCHANDRA HOLLA — MBBS, MD (Medical Genetics) · Reg. No. 8532
"CYP2C19 genotyping is a clinically actionable pharmacogenomic test recommended by the Clinical Pharmacogenetics Implementation Consortium (CPIC). It is particularly important for patients prescribed clopidogrel, certain proton pump inhibitors, voriconazole, and some antidepressants. Identifying a patient's CYP2C19 metabolizer status before or during therapy can help prevent adverse drug reactions and ensure optimal drug efficacy. I recommend this test for any patient who has experienced unexpected side effects or inadequate response to CYP2C19-substrate medications."
Last medically reviewed: September 7, 2026
Test Parameters & Specifications
Sample Stability
- Hemolyzed blood samples
- Insufficient sample volume (less than 2 mL)
- Missing or incomplete Genomics Clinical Information Requisition Form (Form 20)
- Samples collected in incorrect tube type (non-EDTA)
- Frozen samples
- Samples without proper labeling or patient identification
Understanding Your Results
Patient carries two normal-function alleles (e.g., *1/*1). Standard drug doses are expected to be effective. No dose adjustments typically required.
Patient carries one normal-function and one reduced- or no-function allele (e.g., *1/*2, *1/*3). Reduced CYP2C19 enzyme activity may lead to higher drug levels or slower metabolism. Dose adjustments or alternative medications may be considered depending on the drug.
Patient carries two no-function alleles (e.g., *2/*2, *2/*3, *3/*3). Little to no CYP2C19 enzyme activity. Significant risk of drug toxicity or treatment failure with standard doses. Alternative drugs not metabolized by CYP2C19 are often recommended. For example, clopidogrel may be ineffective and alternative antiplatelet agents (e.g., prasugrel, ticagrelor) may be preferred.
Patient carries one or two increased-function alleles (e.g., *1/*17, *17/*17). Increased CYP2C19 enzyme activity may result in faster drug clearance, potentially leading to subtherapeutic drug levels. Higher doses or alternative agents may be needed to achieve therapeutic effect.
Consult your physician if you experience any of the following after taking a medication: unexplained abdominal pain, persistent headache, dizziness, nausea or vomiting, unexplained fever, skin rashes, or difficulty breathing. Your physician may recommend the CYP2C19 Genotyping Test to determine if your symptoms are related to altered drug metabolism. Additionally, consult your doctor before starting any new CYP2C19-substrate medication if you have a known history of adverse drug reactions or treatment failures.
Limitations
- ⚠This test detects only the specific CYP2C19 variants included in the assay panel; rare or novel variants not covered will not be identified
- ⚠Results reflect germline genetic status and do not account for epigenetic, environmental, or drug-drug interaction factors
- ⚠Metabolizer phenotype predictions are based on known genotype-phenotype correlations and may not capture all clinical variability
- ⚠Results should always be interpreted in conjunction with clinical history and other relevant diagnostic information
- ⚠This test does not replace therapeutic drug monitoring (TDM) when clinically indicated
Risks & Considerations
- ●Minor bruising or soreness at the needle insertion site
- ●Slight risk of infection at the puncture site (rare with proper technique)
- ●Lightheadedness or dizziness during or after blood draw (uncommon)
- ●No significant genetic or long-term risks associated with this test
Interfering Factors
- ●Recent blood transfusion (within 120 days) may contaminate DNA with donor alleles
- ●Prior bone marrow or stem cell transplant may yield mixed DNA profiles
- ●Sample contamination or improper handling during collection
- ●Hemolyzed or degraded DNA samples may affect assay performance
Compare With Similar Tests
| Test | CYP2C19 Genotyping Test | CYP2D6 Genotyping Test | CYP2C9 Genotyping Test | Comprehensive Pharmacogenomic Panel |
|---|---|---|---|---|
| Comparison | CYP2C19 Genotyping Test | CYP2D6 genotyping assesses drug metabolism for opioids, antidepressants, tamoxifen, and antipsychotics, while CYP2C19 focuses on clopidogrel, PPIs, certain antidepressants, and voriconazole. Both are pharmacogenomic tests but cover different drug substrates. | CYP2C9 genotyping evaluates metabolism of warfarin, NSAIDs, and some diabetes medications. CYP2C19 covers a different panel of drugs. Both genes belong to the cytochrome P450 family but have distinct clinical applications. | A comprehensive panel tests multiple pharmacogenes (CYP2C19, CYP2D6, CYP2C9, VKORC1, DPYD, TPMT, etc.) simultaneously. The CYP2C19 test is a focused single-gene test suitable when there is a specific clinical indication related to CYP2C19-substrate drugs. |
Frequently Asked Questions
What is the CYP2C19 Genotyping Test?
Who should get the CYP2C19 Genotyping Test?
What medications are affected by CYP2C19 gene variations?
What does it mean to be a Poor Metabolizer for CYP2C19?
What is the cost of the CYP2C19 Genotyping Test at DNA Labs India?
Is fasting required for the CYP2C19 Genotyping Test?
How is the CYP2C19 Genotyping Test performed?
How long does it take to get CYP2C19 Genotyping Test results?
Does the CYP2C19 Genotyping Test need to be repeated?
What sample type is required for the CYP2C19 Genotyping Test?
Is the CYP2C19 Genotyping Test available for home sample collection?
Can CYP2C19 gene variations be treated or corrected?
Related Tests
Reference Laboratory Services
We serve as a reference laboratory for hospitals and clinics across India. Send samples from your facility with same-day pickup, priority processing, and results delivered through our online portal. Competitive institutional pricing available.
Your Data Privacy
Your medical data is protected under Indian law.
✓ Stored in India: All patient records are stored on servers located in India. No data is transferred outside the country.
✓ DPDP Act Compliant: Under the Digital Personal Data Protection Act 2023, you can request deletion of your records at any time by contacting support.
Book Your Test
Enter your details and we'll connect you within 15 minutes.