The main indications for prescribing a blood test for D-dimer:

suspicion of deep vein thrombosis (exclusion test);
pulmonary embolism;
disseminated intravascular coagulation syndrome (DVZ);
complicated course of pregnancy (gestosis, preeclampsia, diabetes and kidney disease).

In the morning on an empty stomach, you can drink clean still water. Venous blood from 2 years. The day before, it is necessary to exclude from the diet fatty or spicy food and alcohol, as well as physical activity.