ANTICOAGULANTS (Systemic)
Some commonly used brand names are:
In the U.S.?
In Canada?
- Coumadin 4
- Sintrom 1
- Warfilone 4
Other commonly used names are nicoumalone and dicoumarol.
Note: | For quick reference, the following anticoagulants are numbered tomatch the corresponding brand names. |
This information does not apply to ardeparin, dalteparin, danaparoid,enoxaparin, or heparin.
Category
- Anticoagulant?Acenocoumarol; Anisindione; Dicumarol; Warfarin
Description
Anticoagulants decrease the clotting ability of the blood andtherefore help to prevent harmful clots from forming in the blood vessels.These medicines are sometimes called blood thinners, although they do notactually thin the blood. They also will not dissolve clots that already haveformed, but they may prevent the clots from becoming larger and causing moreserious problems. They are often used as treatment for certain blood vessel,heart, and lung conditions.
In order for an anticoagulant to help you without causing serious bleeding,it must be used properly and all of the precautions concerning its use mustbe followed exactly. Be sure that you have discussed the use of this medicinewith your doctor. It is very important that you understand all of your doctor'sorders and that you are willing and able to follow them exactly.
Anticoagulants are available only with your doctor's prescription, in thefollowing dosage forms:
Oral- Acenocoumarol
- Anisindione
- Dicumarol
- Warfarin
- Tablets (U.S. and Canada)
Parenteral- Warfarin
- Injection (U.S. and Canada)
Before Using This Medicine
In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For anticoagulants,the following should be considered:
Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to an anticoagulant. Also tell your health care professionalif you are allergic to any other substances, such as foods, preservatives,or dyes.
Pregnancy?Anticoagulants may cause birth defects. They mayalso cause other problems affecting the physical or mental growth of the fetusor newborn baby. In addition, use of this medicine during the last 6 monthsof pregnancy may increase the chance of severe, possibly fatal, bleeding inthe fetus. If taken during the last few weeks of pregnancy, anticoagulantsmay cause severe bleeding in both the fetus and the mother before or duringdelivery and in the newborn infant.
Do not begin taking this medicine during pregnancy,and do not become pregnant while taking it, unless you have first discussedthe possible effects of this medicine with your doctor. Also, if you suspectthat you may be pregnant and you are already taking an anticoagulant, checkwith your doctor at once. Your doctor may suggest that you take a differentanticoagulant that is less likely to harm the fetus or the newborn infantduring all or part of your pregnancy. Anticoagulants may also cause severebleeding in the mother if taken soon after the baby is born.
Breast-feeding?Warfarin is not likely to cause problems in nursingbabies. Other anticoagulants may pass into the breast milk. A blood test canbe done to see if unwanted effects are occurring in the nursing baby. If necessary,another medicine that will overcome any unwanted effects of the anticoagulantcan be given to the baby.
Children?Very young babies may be especially sensitive tothe effects of anticoagulants. This may increase the chance of bleeding duringtreatment.
Older adults?Elderly people are especially sensitive to the effectsof anticoagulants. This may increase the chance of bleeding during treatment.
Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. Many different medicines can affect the way anticoagulants work in your body. Therefore, it is very important that your health care professionalknows if you are taking any other prescriptionor nonprescription (over-the-counter [OTC]) medicine, especially:
- Amiodarone (e.g., Cordarone) or
- Cimetidine (e.g., Tagamet) or
- Metronidazole (e.g., Flagyl) or
- Omeprazole (e.g., Prilosec) or
- Zafirlukast (e.g., Accolate)?Effects of anticoagulants maybe increased because of slower removal from the body
- Anabolic steroids (nandrolone [e.g., Anabolin], oxandrolone [e.g.,Anavar], oxymetholone [e.g., Anadrol], stanozolol [e.g., Winstrol]) or
- Androgens (male hormones) or
- Antifungals, azole (e.g., Diflucan) or
- Antithyroid agents (medicine for overactive thyroid) or
- Aspirin or other salicylates, including bismuth subsalicylate (e.g.,Pepto-Bismol) or
- Cephalosporins (medicine for infection) or
- Cinchophen or
- Clofibrate (e.g., Abitrate, Atromid-S) or
- Danazol (e.g., Danocrine) or
- Dextrothyroxine or
- Diflunisal or
- Disulfiram (e.g., Antabuse) or
- Fluvoxamine (e.g., Luvox) or
- Inflammation or pain medicine (except narcotics) or
- Lepirudin (e.g., Refludan) or
- Medications causing low platelet count or
- Paroxetine (e.g., Paxil) or
- Propafenone (e.g., Rythmol) or
- Quinidine (e.g., Quinidex) or
- Sertraline (e.g., Zoloft) or
- Sulfapyridine or
- Sulfasalazine (e.g., Azulfidine) or
- Thyroid hormones or
- Ticlopidine (e.g., Ticlid) or
- Zileuton (e.g., Zyflo)?These medications may increase the effectsof anticoagulants and may increase the chance of bleeding
- Carbenicillin by injection (e.g., Geopen) or
- Dipyridamole (e.g., Persantine) or
- Divalproex (e.g., Depakote) or
- Moxalactam (e.g., Moxam) or
- Pentoxifylline (e.g., Trantal) or
- Plicamycin (e.g., Mithracin) or
- Sulfinpyrazone (e.g., Anturane) or
- Thrombolytic agents (medicine for blood clots) or
- Ticarcillin (e.g., Ticar) or
- Valproic acid (e.g., Depakene)?Using any of these medicinestogether with anticoagulants may increase the chance of bleeding
- Alcohol (with chronic use) or
- Barbiturates or
- Carbamazepine (e.g., Tegretol) or
- Corticosteroids (cortisone-like medicine) or
- Glutethimide (e.g., Doriden) or
- Griseofulvin (e.g., Fulvicin) or
- Phenylbutazone (e.g., Butazolidin) or
- Phenytoin (e.g., Dilantin) or
- Primidone (e.g., Mysoline) or
- Rifampin (e.g., Rifadin)?Effects of anticoagulants may be decreasedbecause of faster removal from the body
- Vitamin K (e.g., AquaMEPHYTON)?Vitamin K helps produce someimportant blood clotting factors and may decrease the effects of anticoagulantsif used at the same time
Other medical problems?The presence of other medicalproblems may affect the use of anticoagulants. Many medicalproblems and treatments will affect the way your body responds to this medicine. Make sure you tell your doctor if you have any other medical problems, or if you have recently had any of the followingconditions or medical procedures, especially:
- Aneurysm (swelling in a blood vessel) especially in the head or chestor
- Bleeding in the brain or
- Blood disorders or diseases, especially thrombocytopenia (low plateletcount), polycythemia (high red blood cell count), or leukemia or
- Bruising, excessive or
- Cancer of the internal organs, especially of the abdomen or
- Childbirth, recent or
- Type 2 diabetes mellitus or
- Diverticulitis or
- Falls or blows to the body or head or
- Heart infection or
- Hemophilia or other bleeding problems or
- Hypertension (high blood pressure) or
- Inflammation of blood vessels or
- Intestinal problems, especially conditions that may affect the absorptionof food or vitamins or
- Liver disease or
- Pregnancy, terminated or
- Spinal anesthetics or spinal puncture or
- Surgery, major, especially of the head or eye, or dental surgeryor
- Toxemia of pregnancy or
- Ulcers, active, of the stomach, lung, or urinary tract or
- Vitamin K deficiency or
- Wounds, open, surgical or from an ulcer?These conditions mayincrease the chance of bleeding
In addition, it is important that you tell your doctor if you are nowbeing treated by any other medical doctor or dentist.
Proper Use of This Medicine
Take this medicine only as directed by your doctor. Do not take moreor less of it, do not take it more often, and do not take it for a longertime than your doctor ordered. This is especially important for elderly patients,who are especially sensitive to the effects of anticoagulants. Also, it isbest if you take this medicine at the same time each day.
Your doctor or health care professional should checkyour progress at regular visits. A blood test must be taken regularlyto see how fast your blood is clotting. This will help your doctor decideon the proper amount of anticoagulant you should be taking each day. Somepatients may be able to test their blood at home; discuss with your doctorwhether or not this is possible for you.
Dosing?The dose of these medicines will be differentfor different patients. Follow your doctor's orders orthe directions on the label. The following information includes onlythe average doses of these medicines. If your dose isdifferent, do not change it unless your doctor tells you to do so.
For acenocoumarol- For oral dosage form (tablets):
- For preventing or treating harmful blood clots:
- Adults?The usual dose is 1 to 10 milligrams (mg) per day, adjustedaccording to blood tests.
- Children?Dose must be determined by your doctor.
For anisindione- For oral dosage form (tablets):
- For preventing or treating harmful blood clots:
- Adults?The usual dose is 25 to 250 milligrams (mg) per day,adjusted according to blood tests.
- Children?Dose must be determined by your doctor.
For dicumarol- For oral dosage form (tablets):
- For preventing or treating harmful blood clots:
- Adults?The usual dose is 25 to 200 milligrams (mg) per day,adjusted according to blood tests.
- Children?Dose must be determined by your doctor.
For warfarin- For oral dosage form (tablets):
- For preventing or treating harmful blood clots:
- Adults?The starting dose is usually 2 to 5 milligrams (mg)per day for two to four days. Then, your dose may be adjusted, depending onyour condition and results of routine blood tests.
- Children?Dose must be determined by your doctor.
- For injection dosage form:
- For preventing or treating harmful blood clots:
- Adults?The starting dose is usually 2 to 5 milligrams (mg)per day for two to four days. Then, your dose may be adjusted, depending onyour condition and results of routine blood tests.
- Children?Dose must be determined by your doctor.
Missed dose?If you miss a dose of this medicine, take it assoon as possible. Then go back to your regular dosing schedule. If you donot remember until the next day, do not take the missed dose at all and donot double the next one. Doubling the dose may causebleeding. Instead, go back to your regular dosing schedule. It is recommendedthat you keep a record of each dose as you take it to avoid mistakes. Also,be sure to give your doctor a record of any doses you miss. If you have anyquestions about this, check with your doctor.
Storage?To store this medicine:
- Keep out of the reach of children.
- Store away from heat and direct light.
- Do not store this medicine in the bathroom, near the kitchen sink,or in other damp places. Heat or moisture may cause the medicine to breakdown.
- Do not keep outdated medicine or medicine no longer needed. Be surethat any discarded medicine is out of the reach of children.
Precautions While Using This Medicine
Tell all medical doctors, dentists, and pharmacists you go tothat you are taking this medicine.
Check with your doctor right away if you notice anyunusual bleeding or bruising.
Check with your health care professional before youstart or stop taking any other medicine, or change the amount you are taking. This includes any nonprescription (over-the-counter [OTC]) medicine,even aspirin or acetaminophen. Many medicines change the way this medicineaffects your body. You may not be able to take the other medicine, or thedose of your anticoagulant may need to be changed.
It is important that you carry identification statingthat you are using this medicine. If you have any questions about whatkind of identification to carry, check with your health care professional.
While you are taking this medicine, it is very important that you avoidsports and activities that may cause you to be injured. Report to your doctorany falls, blows to the body or head, or other injuries, since serious internalbleeding may occur without your knowing about it.
Be careful to avoid cutting yourself. This includes taking special carein brushing your teeth and in shaving. Use a soft toothbrush and floss gently.Also, it is best to use an electric shaver rather than a blade.
Drinking too much alcohol may change the way this anticoagulant affectsyour body. You should not drink regularly on a daily basis or take more than1 or 2 drinks at any time. If you have any questions about this, check withyour doctor.
The foods that you eat may also affect the way this medicine affects yourbody. Eat a normal, balanced diet while you are taking this medicine. Do not go on a reducing diet, make other changes in your eatinghabits, start taking vitamins, or begin using other nutrition supplementsunless you have first checked with your health care professional. Also,check with your doctor if you are unable to eat for several days or if youhave continuing stomach upset, diarrhea, or fever. These precautions are importantbecause the effects of the anticoagulant depend on the amount of vitamin Kin your body. Therefore, it is best to have the same amount of vitamin K inyour body every day. Some multiple vitamins and some nutrition supplementscontain vitamin K. Vitamin K is also present in green, leafy vegetables (suchas broccoli, cabbage, collard greens, kale, lettuce, and spinach) and somevegetable oils. It is especially important that you do not make large changesin the amounts of these foods that you eat every day while you are takingan anticoagulant.
Check with your doctor if you are unable to eat for several days or ifyou have continuing stomach upset, diarrhea, or fever. This could decreasethe amount of vitamin K that gets into your body and could affect this medicine.
Be careful if the weather is very hot for several days. This could increasethe effects of the medicine.
After you stop taking this medicine, your body will need time to recoverbefore your blood clotting ability returns to normal. Your health care professionalcan tell you how long this will take depending on which anticoagulant youwere taking. Use the same caution during this periodof time as you did while you were taking the anticoagulant.
Side Effects of This Medicine
Along with its needed effects, a medicine may cause some unwanted effects.Although not all of these side effects may occur, if they do occur they mayneed medical attention.
Since many things can affect the way your bodyreacts to this medicine, you should always watch for signs of unusual bleeding.Unusual bleeding may mean that your body is getting more medicine than itneeds. Check with your doctor immediately if any of thefollowing signs of bleeding or overdose occur:
Bleeding from gums when brushing teeth; blood in urine; nosebleeds; pinpoint red spots on skin; unusual bleeding or bruising; unusually heavy bleeding or oozing from cuts orwounds; unusually heavy or unexpected menstrual bleeding
Signs and symptoms of bleeding inside the body?dose-related
Abdominal or stomach pain or swelling; back pain or backaches; black, tarry stools; bleeding in eye; blood in stools; blood in vomit or vomit that looks like coffee grounds; blood in urine; blurred vision; chest pain; confusion; constipation; coughing up blood; diarrhea (sudden and severe); dizzinessor fainting; headache (continuing or severe); joint pain, stiffness, or swelling; loss of appetite; nausea and vomiting (severe); nervousness; numbness or tingling ofhands, feet, or face; paralysis; shortness of breath; weakness (sudden)
Also, checkwith your doctor as soon as possible if any of the following side effectsoccur:
Rare
Blisters or itching on skin; blue orpurple toes; dark urine; pain in toes; painful red sores on skin, especiallyon thighs, breasts, penis, or buttocks; sores, ulcers,or white spots in mouth or throat; sudden increaseor decrease in amount of urine; swelling of face,feet, and/or lower legs; trouble in breathing; yellow eyes or skin
Other side effects may occur that usually donot need medical attention. These side effects may go away during treatmentas your body adjusts to the medicine. However, check with your doctor if anyof the following side effects continue or are bothersome:
These medicinessometimes cause temporary loss of hair on the scalp.
Depending on your diet, anisindione may causeyour urine to turn orange. Since it may be hard to tell the difference betweenblood in the urine and this normal color change, check with your doctor ifyou notice any color change in your urine.
Other side effects not listed above may also occur in some patients. Ifyou notice any other effects, check with your doctor.
Revised: 5/18/99
