INR Blood Test
On warfarin and need an INR check? Walk in 7 days a week, get same-day results, and avoid the wait for NHS clinic appointments.
INR (International Normalised Ratio) measures how long your blood takes to clot. If you take warfarin or another vitamin K antagonist, regular INR testing is essential to ensure your dose keeps your blood within the safe therapeutic range.
An INR that is too low means your blood may clot too easily, increasing stroke or DVT risk. Too high, and you are at increased risk of bleeding. The target range depends on why you take anticoagulants, typically between 2.0 and 3.0 for most conditions, or 2.5 to 3.5 for mechanical heart valves.
Who needs regular INR testing:
- • Patients on warfarin for atrial fibrillation
- • Those with mechanical heart valves
- • People with a history of blood clots (DVT, PE)
- • Anyone on vitamin K antagonist therapy
Why test at Medical Express Clinic:
- • Walk-in appointments available 7 days a week
- • Results the same day
- • GP review included in the price
- • No need to wait for NHS clinic availability
- • Central London location, CQC registered
If your INR is outside the target range, our GP can advise on dose adjustment or refer you back to your anticoagulation clinic with the results.
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Dr Penelope Sheehan
Health Screening, Paediatrics and Menopause • GMC 6056535
This page was medically reviewed on 2 July 2026.
"Specialising in women's health, hormonal balance, and menopause management within screening contexts. Dr Sheehan also has dedicated weight-loss management training and experience in safe GLP1 agonist prescribing alongside a special interest in paediatric assessments and consultations. Her compassionate and understanding approach is particularly valued by our patients."
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INR Blood Test
£39.38Related blood tests
Common questions
Q.Do I need an appointment?
Walk-ins welcome 7 days a week, or book a specific time if you prefer.
Q.Can you adjust my warfarin dose?
Our GP can advise on dose adjustment based on your result. We can also send results directly to your anticoagulation clinic if you prefer.
Q.I'm travelling - can I get my INR checked before I go?
Yes. Many patients use us for one-off tests between regular clinic appointments or before travel.
