(IM) to infants at birth to prevent infant hemorrhagic disease. Infants are administered
this medication because at birth they lack the normal intestinal flora required to produce
enough Vitamin K to play its role in blood clotting. When phytonadione is used for its
anticoagulant effects, the dosage is based on the level of warfarin anticoagulation in the
patient. This level of anticoagulation is determined by blood sample and expressed as
the International Normalized Ratio (INR) by the laboratory. Doses may be as small as
0.5-1 mg (oral) up to 10 mg administered subcutaneously. The initial effects of vitamin
K take up to 6 hours with maximum effects in 2-3 days. If a patient is actively bleeding,
the coagulant of choice may be fresh frozen plasma or a blood transfusion. Side effects
associated with this agent include "flushing" sensations and peculiar sensations of taste.
The injectable form of this agent is used only on an inpatient basis (that, in the hospital
or emergency room), and it should be remembered that it should only be administered
subcutaneously--severe reactions (including death) have been reported when the
product was given intravenously (IV). Phytonadione will not counteract the
anticoagulant action of heparin.
b. Vitamin K3, Menadione. Menadione is another coagulant prescribed in
patients who have bleeding problems. The only side effect of real concern with
menadione is hepatomegaly. Hepatomegaly is a condition in which the liver becomes
enlarged because of an excess of fat soluble vitamins stored in the lipid tissue. This
agent is commonly supplied in tablet form.
c. Menadiol (Synkayvite). Menadiol (observe its similiarity to menadione) is a
synthetic Vitamin K3. Menadiol is also used as a coagulant available in a tablet and
injectable form.
d. Specific Clotting Factors. In patients that have an acquired or hereditary
clotting factor deficiency, specific clotting factors are available. Factor VIII and Factor IX
are available as concentrates often stocked within the pharmacy. The agents are
available for minor procedures or surgery in select patients with these deficiencies.
e. Desmopressin Acetate (DDAVP). Desmopresin is a synthetic analog of
vasopressin, the naturally occurring human antidiuretic hormone. It has the unique
activity of producing a dose-related increase in circulating Factor VIII and von
Willdebrand's factor levels. Both of these factors are essential to normal human
coagulation. This agent is used in individuals with Hemophilia A (lacking factor VIII) or
von Willdebrand's disease. Desmopressin will maintain homeostasis in these patients
during surgery and post-operatively. Desmopressin may also be prescribed for
uncontrolled bleeding related to surgery in patients without a coagulation dysfunction.
f. Aminocaproic Acid (Amicar). Aminocaproic acid is an agent that inhibits
fibrinolysis (clot breakdown) by inhibiting plasminogen activators. Consequently, it
stabilizes clots in excessive bleeding. Aminocaproic acid is given either intravenously
or orally. Individuals with bleeding dysfunction (hemophilia) may take this product 12-24
hours prior to a dental procedure or surgery. It is often prescribed with desmopressin.
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