In people with coagulation disorders, except for a specific medical criterion, small-volume intramuscular injections, such as the ones used for vaccination, can be applied with reasonable security. The use of a 0.5 or 0.6 mm (25G or 23G) fine needle, and after vaccination maintaining pressure at the injection site (without scrubbing) for 2 minutes, is recommended. In any case, the person being vaccinated must be informed about the possibility of a hematoma at the injection site.
People on chronic treatment with anticoagulants, who are under control and have a stable INR, can receive intramuscular vaccination without any problem.
If there is any doubt, a doctor should assess the individual case to determine the possibility of getting (or giving) the vaccine.