Anticoagulants prevent the coagulation or clotting of blood. These drugs are given to prevent your blood from clotting by increasing the time it takes for the blood to clot.


Heparin is not given to break up a clot. Know that this would be given to prevent fibrin from forming a clot. The two things that should come to your mind is deep vein thrombosis and pulmonary emboli being prevented. Here’s a question for you. How does fibrin get prevented from forming a clot?

The conversion of prothrombin to thrombin and fibrinogen to fibrin is blocked. Thrombin is no longer a pro. Fibrin is no longer a -ogen.

PT and PTT lab reports belong to Coumadin and Heparin, but how do you remember which belongs to what anticoagulant? Heparin starts with the letter H. Technically if you write two lowercase t next to each other like this (tt) it can look like the letter H. there are two t’s in PTT. Therefore the lab report PTT, or known as partial thromboplastin time levels is for Heparin. REMEMBER that the PTT and aPTT, also known as activated PTT, should be 1.5 to 2 times the normal range.

Also, there are two tt’s in protamine sulfate. Now you can’t forget that protamine sulfate is the antidote for Heparin.

Heparin is rapid acting and is given intravenously or subcutaneously. You do not have to go crazy over Lovenox. Lovenox is a Heparin but it does not require PTT or aPTT monitoring.

Who do you not given Heparin to? Do not even THINK about giving Heparin to anyone with bleeding conditions or patients who are undergoing surgery. Yes, this includes lumbar puncture.

Patients who are on dialysis are likely to receive Heparin. Blood is leaving the body and can easily clot so Heparin maintain the flow of blood to prevent the clotting.


The lab report for Coumadin is PT. The antidote for Coumadin is vitamin K. The easy way to remember that is that Coumadin starts with the letter C. C and K sounds alike.

Make sure you do not give Coumadin to patients with bleeding disorders, such as hemophilia. If a patient has a vitamin K deficiency, they also cannot receive Coumadin.

If you give Coumadin to a pregnant woman, you are asking to lose your license. Pregnant women are more likely to receive Heparin. Coumadin is considered category X and can cross into breast milk.

What happens if you give too much Coumadin to the patient?

Think of the blood getting extra thin to the point where the patient can have hemorrhaging and bruising. This will lead to increased heart rate because the heart is trying to push the blood out faster. The blood pressure will drop as a result. You definitely want to WATCH OUT FOR SPONTANEOUS BLEEDING. Also, be on alert for patients who can have a red-orange urine. That’s not normal.

Why should you teach the client to decrease intake of green leafy vegetables?

Since vitamin K is the antidote to Coumadin, then green leafy vegetables would affect Coumadin as well. You have to associate green leafy vegetables with vitamin K.

HT: Mosby’s Pharmacology Memory NoteCards: Visual, Mnemonic, and Memory Aids for Nurses, 4e