DPYD Testing Before — 5-FU and Capecitabine
5-FU and capecitabine are two of the most widely used chemotherapy drugs in India. A gene variant carried by some patients means a standard first dose can cause severe, life-threatening harm. A single blood test, done before treatment starts, identifies this risk.
Medically reviewed by Dr. Bharati Devi Gorantla, Medical Oncologist, MBBS · MD · DM (Adyar, Chennai) · ECMO · MRCP SCE (UK) · Last reviewed September 2026
- A single blood test — DPYD genotyping needs to be done only once and requires a standard blood draw.
- Not routinely offered — Most patients in India are not offered this test unless they raise it with their team.
- The risk is genetic — DPD deficiency runs in families. A close relative who reacted badly to 5-FU raises your own risk.
- The test guides the plan — Your oncologist uses the result to decide whether and how to proceed — not to refuse treatment automatically.
on Panel
Survival Rate*
Treated
(800+ reviews)
DPYD testing looks for a gene variant that stops your body from breaking down 5-FU and capecitabine safely. In people who carry this variant, a standard first dose can accumulate to toxic levels. The test is a blood draw done once before treatment. ESMO and CPIC both recommend it before starting either drug.
What does DPYD testing check for?
DPYD testing checks whether your body can safely process 5-FU and capecitabine by looking for variants in the gene that makes the DPD enzyme. DPD is the enzyme responsible for breaking the drug down after it has done its work.
If this gene carries a variant that reduces DPD activity, the drug has nowhere to go — it builds up in your bloodstream to toxic levels.
The risk is not uniform. Partial deficiency may mean a lower dose is manageable; complete deficiency means a standard first dose can be life-threatening. Your oncologist interprets the result and decides what to do next.
What should you ask your oncologist before the first dose?
- Ask whether DPYD testing is available through your centre or a partner laboratory
- Ask when the test needs to be done so the result is ready before your first infusion is scheduled
- Tell your team if a close family member has had a severe reaction to 5-FU or capecitabine
- Ask what the result will mean for your treatment plan before you begin
- If testing is not available locally, ask whether a referral to a centre that offers it is possible
Where to find us
Our centres in and around Hyderabad
Addressed by landmark, because that is how this city navigates. Each centre also names the areas it serves, so you can place it without a map. Consultation and day-care Chemotherapy run at every one of them.
17+ senior cancer specialists. One panel for your case.
Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Dr. Muralidhar Muddusetty
MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)
Dr. Vinay Mamidala
MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)
Dr. Vajja Sandeep Kumar
MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
You do not have to work this out alone
A 45-minute consultation with a specialist who treats this every week.
Can you get DPYD testing in India?
Specialist genetic laboratories in India do offer DPYD genotyping. It is not yet a routine part of pre-chemotherapy workup at most centres, and most patients are not offered it unless they raise it themselves.
Arrangements vary by centre. Your oncologist can check whether the laboratory your centre works with carries this test, or whether the sample needs to be sent elsewhere. Ask well before your first infusion is scheduled, not on the day.
Because availability changes, the most reliable step is to raise the question directly with your treating team. They are best placed to tell you what is accessible to you now.
Did you know?
The European Medicines Agency updated its guidance in 2020 to require DPYD testing before fluoropyrimidine therapy across Europe. The change followed documented cases where patients died or came close to death from a first dose — patients who would have been identified by testing beforehand.
Most patients in India are not yet offered this test before starting 5-FU or capecitabine.
Source: European Medicines Agency: DPYD testing guidance for fluoropyrimidine medicines, 2020
Explore 24 more Before You Start: Tests, Ports & Fertility topics
Pharmacogenomic & Pre-Treatment Safety Testing
- DPYD Testing Before 5-FU and Capecitabine
- Heart, Kidney and Hearing Tests Before Chemotherapy
- Safety Tests Before Your First Chemotherapy Dose
- Should You Ask for Pharmacogenomic Testing?
- TPMT and NUDT15 Testing Before Thiopurines
- UGT1A1 Testing Before Irinotecan
- What If a Safety Test Comes Back Abnormal?
- What Is DPD Deficiency?
Before You Start: Tests & Preparation
HUB — Before You Start Chemotherapy
Ports, PICC Lines & Cannulas
- Cannula Chemotherapy: Managing Difficult Veins
- Chemotherapy Ports and Lines: Which Do You Need?
- Do You Really Need a Port?
- Does a Port Hurt?
- Extravasation: When Chemotherapy Leaks From the Vein
- Looking After Your Port Between Cycles
- Looking After a PICC Line at Home
- Port Infection: Signs and What to Do
- Port Insertion: What the Procedure Involves
- Port vs PICC Line: Which Is Better?
- What Is a Chemotherapy Port?
- What Is a PICC Line?
- What to Report Immediately During an Infusion
- When and How Is a Port Removed?
Still not sure what applies to you?
Send your reports across and a senior medical oncologist will go through what they mean, what is known, and what the options actually are.
Frequently asked questions
What happens if you have DPD deficiency and receive 5-FU without testing?
Without testing, there is no way to know you carry the variant before you react. In patients with significant DPD deficiency, a standard dose of 5-FU or capecitabine can cause severe toxicity affecting the gut lining, mouth, bone marrow, and nervous system. Some of these reactions are life-threatening and can begin with the first infusion. The value of testing is that it identifies this risk before any dose is given, when it can still change the plan.
How common is DPYD deficiency in Indian patients?
The honest answer is that population data for Indian patients is much thinner than for European populations, and reliable figures specific to South Asian ancestry are not yet established. CPIC guidance acknowledges that variant frequencies differ between populations. What is consistent across populations studied is that DPYD variants do occur. Your oncologist can discuss what is currently understood about risk and whether that changes the case for testing in your situation.
Does a DPYD variant mean you cannot have 5-FU or capecitabine at all?
Not automatically. A result showing partial DPD deficiency does not rule out the drug — it changes the conversation about how to proceed, which is a decision for your oncologist. Complete deficiency is a different situation, and your team will weigh whether the drug should be used at all. Bring the result to your oncologist and ask what it means for your specific plan. This page carries no dose or dose-adjustment guidance.
How long does the DPYD test result take?
Genotyping panels generally return results within one to two weeks, though turnaround varies by laboratory. Ask when the test is requested — not after. If your first infusion is already booked within days, tell your team immediately so they can factor the timeline into the schedule. Planning ahead is the part you can control.
Is DPYD testing covered by health insurance in India?
Coverage varies between insurers and there is no universal rule. Ask your insurer directly whether pharmacogenomic testing is included under your policy. If cost is a concern, ask your oncologist or the hospital's patient services team — they will know which laboratories charge what and whether any subsidised options are available through your centre.
Which cancers use 5-FU or capecitabine?
5-FU and capecitabine are among the most widely used chemotherapy drugs across oncology. They appear in regimens for colorectal cancer, gastric cancer, oesophageal cancer, breast cancer, and certain head and neck cancers, among others. They are also given as part of combination regimens you may recognise by name. If your plan includes either drug in any form, the DPYD question applies to you. Check with your oncologist if you are unsure whether your regimen contains a fluoropyrimidine.
What is the difference between DPYD genotyping and phenotyping?
Genotyping sequences the DPYD gene to look for known variants. Phenotyping measures how well your body actually processes the drug's building blocks — typically by checking the level of uracil in your blood before treatment. Both approaches identify DPD deficiency, and CPIC supports both. In India, genotyping is the test more likely to be accessible at this time. Ask your oncologist which approach is available at your centre and what it would cover.
If DPYD testing is not available to me, should I still have the treatment?
That is a clinical decision for your oncologist, not something this page can answer. Your oncologist will weigh the cancer being treated, the available options, the urgency of starting, and the limits of what testing can be accessed. What you should do is ask the question directly: tell your team you know about DPYD testing and want to understand what the plan is if it cannot be done. That is always a reasonable question to raise, and your team should be able to explain their reasoning.
Chemotherapy Topics
Browse our complete chemotherapy guide — 1133 pages on side effects, medicines, cost, daily life and care in Hyderabad. Tap any topic to read more.