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Pronunciation |
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(fye
toe na DYE
one) |
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U.S. Brand
Names |
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AquaMEPHYTON® Injection; Konakion®
Injection; Mephyton®
Oral |
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Generic
Available |
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No |
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Synonyms |
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Methylphytyl Napthoquinone; Phylloquinone; Phytomenadione; Vitamin
K1 |
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Pharmacological Index |
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Vitamin, Fat Soluble |
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Use |
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Prevention and treatment of hypoprothrombinemia caused by drug-induced or
anticoagulant-induced vitamin K deficiency, hemorrhagic disease of the newborn;
phytonadione is more effective and is preferred to other vitamin K preparations
in the presence of impending hemorrhage; oral absorption depends on the presence
of bile salts |
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Pregnancy Risk
Factor |
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C |
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Contraindications |
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Hypersensitivity to phytonadione or any component |
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Warnings/Precautions |
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Severe reactions resembling anaphylaxis or hypersensitivity have occurred
rarely during or immediately after I.V. administration (even with proper
dilution and rate of administration); restrict I.V. administration for emergency
use only; ineffective in hereditary hypoprothrombinemia, hypoprothrombinemia
caused by severe liver disease; severe hemolytic anemia has been reported rarely
in neonates following large doses (10-20 mg) of
phytonadione |
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Adverse
Reactions |
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<1%: Transient flushing reaction, rarely hypotension, cyanosis, dizziness
(rarely), pain, abnormal taste, GI upset (oral), hemolysis in neonates and in
patients with G-6-PD deficiency, tenderness at injection site, dyspnea,
diaphoresis, anaphylaxis, hypersensitivity reactions |
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Drug
Interactions |
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Decreased effect: Warfarin sodium, dicumarol, anisindione effects antagonized
by phytonadione; mineral oil may decrease GI absorption of vitamin
K |
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Stability |
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Protect injection from light at all times; may be
autoclaved |
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Mechanism of
Action |
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Promotes liver synthesis of clotting factors (II, VII, IX, X); however, the
exact mechanism as to this stimulation is unknown. Menadiol is a water soluble
form of vitamin K; phytonadione has a more rapid and prolonged effect than
menadione; menadiol sodium diphosphate (K4) is half as potent as
menadione (K3). |
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Pharmacodynamics/Kinetics |
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Onset of increased coagulation factors: Oral: Within 6-12 hours; Parenteral:
Within 1-2 hours; prothrombin may become normal after 12-14 hours
Absorption: Oral: Absorbed from the intestines in the presence of bile
Metabolism: In the liver rapidly
Elimination: In bile and urine |
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Usual Dosage |
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I.V. route should be restricted for emergency use only
Infants: 1-5 mcg/kg/day
Adults: 0.03 mcg/kg/day
Hemorrhagic disease of the newborn:
Prophylaxis: I.M.: 0.5-1 mg within 1 hour of birth
Treatment: I.M., S.C.: 1-2 mg/dose/day
Oral anticoagulant overdose:
Infants: I.M., S.C.: 1-2 mg/dose every 4-8 hours
Children and Adults: Oral, I.M., I.V., S.C.: 2.5-10 mg/dose; rarely up to
25-50 mg has been used; may repeat in 6-8 hours if given by I.M., I.V., S.C.
route; may repeat 12-48 hours after oral route
Vitamin K deficiency: Due to drugs, malabsorption or decreased synthesis of
vitamin K
Infants and Children:
Oral: 2.5-5 mg/24 hours
I.M., I.V.: 1-2 mg/dose as a single dose
Adults:
Oral: 5-25 mg/24 hours
I.M., I.V.: 10 mg |
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Monitoring
Parameters |
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PT |
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Mental Health: Effects
on Mental Status |
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May rarely cause dizziness |
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Mental Health:
Effects on Psychiatric
Treatment |
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None reported |
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Dental Health: Local
Anesthetic/Vasoconstrictor
Precautions |
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No information available to require special precautions |
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Dental Health:
Effects on Dental Treatment |
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No effects or complications reported |
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Patient
Information |
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Oral: Take only as directed; do not take more or more often than prescribed.
Avoid excessive or increased intake of vitamin K containing food (eg, green
leafy vegetables, dairy products, meats) unless recommended by prescriber. Avoid
alcohol and any OTC or prescribed medications containing aspirin that are not
approved by prescriber. Report bleeding gums; blood in urine, stool, or vomitus;
unusual bruising of bleeding; or abdominal cramping. Pregnancy
precautions: Inform prescriber if you are or intend to be
pregnant. |
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Nursing
Implications |
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I.V. administration: Dilute in normal saline, D5W or
D5NS and infuse slowly; rate of infusion should not exceed 1
mg/minute. This route should be used only if administration by another route
is not feasible for phytonadione; I.V. administration should not exceed 1
mg/minute; for I.V. infusion, dilute in PF (preservative free) D5W or
normal saline. |
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Dosage Forms |
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Injection:
Aqueous colloidal: 2 mg/mL (0.5 mL); 10 mg/mL (1 mL, 2.5 mL, 5 mL)
Aqueous (I.M. only): 2 mg/mL (0.5 mL); 10 mg/mL (1 mL)
Tablet: 5 mg |
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Extemporaneous
Preparations |
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A 1 mg/mL oral suspension was stable for only 3 days when refrigerated when
compounded as follows:
Shake well before using and keep in refrigerator
Nahata MC and Hipple TF, Pediatric Drug Formulations, 3rd ed,
Cincinnati, OH: Harvey Whitney Books Co, 1997. |
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References |
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Barash P, Kitahata LM, and Mandel S,
"Acute Cardiovascular Collapse After Intravenous Phytonadione," Anesth
Analg, 1976, 55(2):304-6.
Harrell CC and Kline SS,
"Oral Vitamin K1: An Option to Reduce Warfarin's Activity," Ann
Pharmacother, 1995, 29(12):1228-32.
Hopkins CS,
"Adverse Reaction to a Cremophor-Containing Preparation of Intravenous Vitamin K,"
Intensive Therapy Clin Monit, 1988, 9:254-5.
Martinez-Abad M, Delgado F, Palop V, et al,
"Vitamin K1 and Anaphylactic Shock," DICP, 1991,
25(7-8):871-2.
Michelson AD, Bovill E, Monagle P, et al,
"Antithrombic Therapy in Children," Chest, 1998, 114(5 Suppl):748S-69S.
Shearer MJ, "Vitamin K," Lancet, 1995, 345(8944):229-34.
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