Sintrom (Acenocoumarol) in Spain: Uses and INR Checks

Sintrom is the Spanish brand of acenocoumarol, a blood thinner (anticoagulant) that works like warfarin. It lowers the risk of clots in people with atrial fibrillation, a mechanical heart valve or past clots. In Spain it needs a prescription and regular INR blood tests. Never change or stop it without your doctor.

Dr. Pedro Yelamo Vera is a GP licensed in Spain (Colegiado No. 484814280).

For a medical emergency, call 112 or go to the nearest local emergency department. Do not wait for a video consultation or an online reply.

What is Sintrom used for?

Sintrom slows down the way blood clots. The leaflet says it is used to prevent and treat clots in the blood vessels. Doctors use it for:

• Atrial fibrillation, an irregular heartbeat that can cause clots and strokes.
• Mechanical heart valves.
• Clots in the legs or lungs (deep vein thrombosis or pulmonary embolism), and to stop them coming back.

The tablets come in different strengths. The amount changes from person to person and from week to week, based on blood tests. Only the doctor or the anticoagulation clinic sets it.

Is Sintrom the same as warfarin?

They are not the same medicine, but they work in the same way. Both block vitamin K, which the liver needs to make clotting factors. Acenocoumarol acts for a shorter time than warfarin. In Spain, Sintrom is the blood thinner of this type most people take. Warfarin is also sold in Spain as Aldocumar.

Name	Medicine	Where
Sintrom	Acenocoumarol	Spain (prescription)
Sinthrome	Acenocoumarol	UK (prescription, less used)
Aldocumar	Warfarin	Spain (prescription)
Warfarin, Coumadin, Jantoven	Warfarin	UK, Ireland, US (prescription)

The tablets are not swapped one for one. If you arrive in Spain on warfarin, keep taking it as prescribed and see a doctor soon. The doctor decides whether to keep warfarin or switch, and plans the extra INR checks a switch needs.

Do you need a prescription for Sintrom in Spain?

Yes. Both Sintrom tablet strengths are listed on the AEMPS CIMA database as prescription medicines for long-term treatment (tratamiento de larga duración). Our guide on which medicines need a prescription in Spain covers other common examples.

How do INR checks work in Spain?

INR is a blood test that shows how long your blood takes to clot. Your doctor sets a target range for you. If the INR is too high, you bleed more easily. If it is too low, a clot can form.

• In Spain the checks are often done at the health centre, by nurses, with a finger-prick test. People call them controles de Sintrom.
• After each check you get a calendar that shows what to take each day until the next test.
• Checks are closer together at the start, after any change, and in people over 65.
• Some people check their INR at home with a meter, after training.

Keep every result and your calendar. If you move within Spain or come from abroad, bring them to your new doctor. Our guide on records for anticoagulation follow-up lists what to gather. Carry your anticoagulation card, so staff know you take Sintrom in an accident.

Which medicines and foods affect Sintrom?

A long list of medicines can push the INR up or down. Some common ones the leaflet names:

• Painkillers and anti-inflammatories: aspirin, ibuprofen and other NSAIDs. Paracetamol and tramadol can also raise the effect.
• Antibiotics and antifungals, such as amoxicillin, erythromycin, quinolones, metronidazole and miconazole, even the gel.
• Heart, cholesterol and stomach medicines, such as amiodarone, some statins and omeprazole.
• Medicines that weaken it, such as rifampicin, carbamazepine and the contraceptive pill.
• Herbal and supplement products: St John's wort weakens it. Vitamin E and glucosamine can raise it.

Tell every doctor, dentist and pharmacist that you take Sintrom, before you start anything new. That includes medicines sold without a prescription. Our guides to ibuprofen and paracetamol explain those two in Spain.

Food and drink. Vitamin K in green leafy vegetables, such as spinach and cabbage, can weaken Sintrom. You do not need to avoid them. Keep the amount steady from week to week, and tell your doctor before a big diet change. The leaflet says to avoid alcohol and cranberry juice.

Who should not take Sintrom?

• Pregnant women. It can seriously harm the baby. Women who could get pregnant need reliable contraception, and should tell their doctor at once if they plan a pregnancy or become pregnant. Our pregnancy care page explains how a GP helps.
• People with active bleeding, such as a stomach ulcer, or a bleeding disorder.
• People with very high blood pressure that is not controlled, or severe liver or kidney disease.
• People who cannot follow the plan safely, as the leaflet notes.

Before surgery or a tooth extraction, tell the doctor or dentist. They decide whether to pause Sintrom and whether you need a short-term injection instead. Never pause it on your own.

What Sintrom does not do

• It does not dissolve a clot that is already there. It stops new clots and stops old ones from growing, while the body clears them.
• It does not treat high blood pressure or cholesterol. Those need their own care. See our high blood pressure page.
• It is not a painkiller and does not help leg pain on its own.

Bleeding on Sintrom: when to call 112

Bleeding is the main side effect. Small bruises and a short nosebleed can happen. See a doctor soon if you have:

• Bleeding gums or nosebleeds without a clear cause, or bruises you cannot explain.
• Pink, red or dark brown urine.
• Periods that are much heavier than usual.
• Yellow skin or eyes, or a painful skin rash.

Call 112 if you hit your head while on Sintrom, even if you feel fine. Also call 112 if you vomit blood, cough up blood, pass black or bloody stools, have bleeding that will not stop, or get a sudden, severe headache. If you take too many tablets by mistake, contact your doctor straight away. If a child swallows any, call the Spanish poison line (91 562 04 20).

If you miss a dose, do not take a double dose to make up for it. Follow the leaflet and tell the doctor at your next INR check.

Talking it through with a doctor by video

Dr. Yelamo is a GP licensed in Spain. He sees adults, children and pregnant patients by video, every day from 07:30 to 20:30 (Spain time). In the visit he will:

• Go through your INR results, your calendar and your other medicines.
• Check whether a new medicine or remedy may clash with Sintrom.
• Explain how INR follow-up works in Spain, and what to bring.
• Tell you when you need an in-person check or urgent care.

Changes to the Sintrom plan, and any switch from warfarin, are made by the doctor who follows your INR. He does not promise any test or prescription before the visit. Where clinically appropriate, following a genuine evaluation. Treatment and prescriptions are issued solely at the doctor's discretion based on evidence-based clinical guidelines.

A prescription is never guaranteed: it is issued only where clinically appropriate after a genuine evaluation, as a private electronic prescription under Spanish law. This service is for urgent, non-emergency care. In an emergency, call 112.

See how the Urgent Care video visit works. It lasts 15 minutes and costs €50.

This guide is general information. It does not replace the package leaflet or the advice of your doctor or pharmacist.

Frequently asked questions

Sources

• AEMPS CIMA: Sintrom package leaflet
• emc: Sinthrome (acenocoumarol) patient leaflet, UK
• MedlinePlus: Warfarin
• NHS: Warfarin

Related guides

• Anticoagulation follow-up in Spain: records for a GP discussion
• Blood test results explained by a GP
• High blood pressure care online
• Which medicines need a prescription in Spain?
• Urgent Care video visit