Pathology & Blood Tests
Fasting vs Non-Fasting, Best Timing, Reports & Expected TAT
Blood tests and pathology reports are a key part of diagnosis and treatment monitoring. This guide helps you know what to do before the test, when to come, and how/when reports are received.
What to Bring (Checklist)
- Doctor’s prescription/advice for tests (if available)
- Any previous blood reports (for comparison)
- List/photos of current medicines (especially sugar/BP/thyroid meds)
- Photo ID (if needed for registration)
- Insurance/scheme details (if applicable)
Fasting vs Non-Fasting (Simple Guide)
A) Common tests that are usually NON-FASTING
(You can come anytime unless your doctor says otherwise.)
- CBC (Complete Blood Count)
- LFT/KFT (Liver/Kidney function)
- Electrolytes
- Thyroid tests (often non-fasting)
- Many tumour markers (often non-fasting)
- Most routine follow-up blood counts for chemo/radiation monitoring
B) Common tests that usually REQUIRE FASTING
(Typically 8–12 hours fasting — water usually allowed.)
- Fasting blood sugar (FBS)
- Lipid profile (cholesterol)
- Fasting insulin / some metabolic tests (as advised)
C) Tests with special timing instructions
- Post-meal sugar (PP) — usually taken 2 hours after meal
- Some hormone tests — may require morning sampling
- Drug levels / specific monitoring tests — as advised by doctor
Important: Fasting rules can differ by test and your medical condition. If you are unsure, call/WhatsApp the centre before coming.
Best Time to Give Samples (Practical Tips)
- For routine blood tests: morning is best (faster processing and same-day workflow)
- If tests are needed before chemo: come as per the chemo team’s advised timing
- If you are diabetic: inform the staff so sampling can be planned safely
Medicine Instructions (Important)
- Do not stop medicines on your own.
- If fasting tests are planned and you take sugar medicines/insulin, ask the team for guidance on timing.
- If you are on blood thinners, it usually doesn’t affect routine blood tests—but always inform the staff.
What to Expect at the Lab (Step-by-Step)
- Registration & billing (if applicable)
- Sample collection (blood/urine/other sample)
- Sample labelling & processing
- Report generation and dispatch
Where and How You Receive Reports
Depending on your centre workflow, reports may be:
- Given at the reception/lab counter, or
- Shared on WhatsApp / Email (hospital discretion) or
(Your centre team will confirm the exact method.)
Expected Report Timelines (TAT – Safe Ranges)
Same day / within 24 hours (common)
- CBC
- Basic blood sugar tests
- Many routine biochemistry tests (LFT/KFT, electrolytes)
24–48 hours (common)
- Some specialized biochemistry / certain tumour markers
- Some urine cultures may take longer (see below)
2–5 days (common)
- Cultures (urine/blood/sputum) and sensitivity testing
- Some advanced markers/tests
3–7 working days or more (case dependent)
- Histopathology (biopsy tissue reports)
- IHC/advanced pathology markers may take additional time
- Molecular/cytogenetic tests may take longer
Note: TAT varies based on test type, sample quality, and if special stains/markers are required.
Common Mistakes to Avoid
- Coming fasting when not needed (or eating when fasting is required)
- Not informing about diabetes medicines/insulin timing
- Not carrying previous reports (comparison helps doctors a lot)
- Leaving before confirming how you’ll receive the report
Disclaimer
Test preparation and timelines can vary by doctor advice and lab protocol. Please follow instructions shared during scheduling or at the collection counter.
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