Warfarin® Tablets for Atrial Fibrillation

An oral anticoagulant helps prevent and treat blood clots. It is used to reduce stroke risk in certain heart rhythm conditions and to treat or prevent deep vein thrombosis and pulmonary embolism. This page explains key facts and how to order with US delivery from Canada so you can compare options, even without insurance.

What Warfarin Is and How It Works

Warfarin® is a vitamin K antagonist that lowers the blood’s tendency to clot. As a warfarin medication, it decreases production of clotting factors made by the liver. The effect is monitored with INR blood tests and adjusted by your prescriber to keep you in a safe range. YouDrugstore is a licensed Canadian pharmacy in Manitoba. Pharmacists review prescriptions before dispensing.

It starts working over several days as existing clotting factors wear off. The treatment is often continued for months or long term, depending on your diagnosis and risk factors. Food and other medicines can change its effect, so steady habits and regular monitoring matter.

Who It’s For

This therapy is prescribed to lower stroke risk in nonvalvular atrial fibrillation and after some heart valve surgeries. It is also used to treat and prevent deep vein thrombosis and pulmonary embolism. Explore related guidance for Atrial Fibrillation and for patients with a Mechanical Heart Valve.

People with active bleeding, significant bleeding risks, or known allergies to ingredients should avoid it. Those who are pregnant or planning pregnancy should discuss safer alternatives. Severe liver disease, poor adherence to blood tests, and heavy alcohol use can raise risks and may require a different plan.

Dosage and Usage

The dose is individualized. Most adults take it once daily at the same time. Your prescriber selects a starting dose and adjusts based on INR checks. Many patients aim for a target INR range guided by diagnosis; follow your clinician’s instructions and the official label.

Try to keep your dietary vitamin K intake consistent from week to week. Sudden changes in leafy greens, certain supplements, or alcohol can shift your INR. Tell your healthcare professional about new medicines, missed doses, or any bleeding.

Strengths and Forms

This medicine comes as scored oral tablets. Availability may vary by manufacturer. Many people recognize color-coded strengths. A common strength used for dose adjustments is warfarin 5 mg, but your prescriber may select a different strength based on your INR.

• 1 mg
• 2 mg
• 2.5 mg
• 3 mg
• 4 mg
• 5 mg
• 6 mg
• 7.5 mg
• 10 mg

Your pharmacy may dispense different manufacturers over time; shape or color can change, but the active ingredient remains the same.

Missed Dose and Timing

If you miss a dose, take it the same day when remembered. If it is the next day, skip the missed dose and resume your usual schedule. Do not double the next dose. Note the date in your log and tell your prescriber at your next INR check, as guidance can vary.

Storage and Travel Basics

Store tablets at room temperature, dry, and away from direct light. Keep them in the original, child-resistant container. Do not store in a bathroom. When you travel, pack your labeled bottle in carry-on luggage and bring a medication list or a copy of your prescription. Time-zone changes usually do not require a dose change; keep a consistent local dosing time.

Benefits

This anticoagulant is well-studied and can be adjusted to your INR results. The therapy is reversible with vitamin K in emergency settings. Once-daily dosing fits many routines. Generic availability may lower out-of-pocket costs compared with some newer options.

Side Effects and Safety

• Mild bleeding gums
• Easy bruising
• Nosebleeds
• Upset stomach or nausea
• Hair thinning

Serious effects can include major bleeding, coughing or vomiting blood, black or tarry stools, severe headache, or signs of stroke. Rare reactions include skin necrosis or purple toe syndrome. Seek urgent care if you notice serious symptoms. Learn more in our guide to Warfarin Side Effects.

Drug Interactions and Cautions

Many medicines can raise or lower this anticoagulant’s effect. Examples include antibiotics, antifungals, amiodarone, antiepileptics, and some cholesterol agents. NSAIDs, aspirin, and other blood thinners can increase bleeding risk. Herbal products like St. John’s wort, ginkgo, and ginseng may interact. Keep a consistent intake of vitamin K–rich foods. See practical diet tips in Foods To Avoid.

Always tell your prescriber and pharmacist about all prescription drugs, OTC products, and supplements. Alcohol can change your INR and increase bleeding risk; ask your clinician about safe limits.

What to Expect Over Time

You will usually have INR checks more often at the start, then less frequently once stable. Dose changes may be needed if your diet, other medicines, or health status changes. Keep a simple log of doses, tests, and any symptoms. Carry an anticoagulant alert card so others know you take this therapy.

Compare With Alternatives

Direct oral anticoagulants such as Eliquis® and Pradaxa® are options for many patients. These do not require routine INR checks but are not right for every condition, such as some mechanical valves. They are not a generic for warfarin; your prescriber will help choose based on your medical history, kidney function, and interactions.

Pricing and Access

Compare Canadian pricing and see how warfarin cost without insurance may fit your budget. Check the product page to review current options and available manufacturers. We offer transparent pricing and secure checkout. This product ships from Canada to US with clear import documentation when required.

If your prescriber changes your dose or brand, you can review alternatives within our Cardiovascular category and discuss with your clinician before switching.

Availability and Substitutions

Stock and manufacturers can vary by time. A valid warfarin prescription is required for dispensing. If a strength or manufacturer is unavailable, your prescriber may recommend a therapeutically equivalent alternative or a different strength combination. We do not promise restock dates.

Patient Suitability and Cost-Saving Tips

This treatment may suit adults who can attend INR checks, keep a consistent diet, and coordinate medicines across prescribers. It may not suit those with a high bleeding risk, planned pregnancy, or barriers to monitoring. Ask your clinician about your individual risks.

To lower out-of-pocket costs, consider multi-month fills when appropriate, keep a steady diet to avoid extra visits, and use refill reminders. Traveling soon? Arrange tests ahead of time and bring enough tablets for your trip.

Questions to Ask Your Clinician

• My INR target: what range and how often to check?
• Diet: how consistent should my vitamin K intake be?
• Interactions: which antibiotics or pain relievers should I avoid?
• Safety: what warning signs require urgent care?
• Procedures: how to manage before dental or surgical work?
• Travel: how to time doses across time zones?
• Alternatives: could a DOAC fit my medical history?

Authoritative Sources

FDA DailyMed: Warfarin Sodium

FDA Medication Guide: Warfarin

Health Canada DPD: Warfarin

Ready to proceed? Order from YouDrugstore for US shipping from Canada with prompt, express shipping and temperature-controlled handling when required. This information is not a substitute for professional medical advice; always follow your prescriber and the official label.