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(phytonadione) Vitamin K1
Phytonadione is a vitamin which is a clear, yellow to amber, viscous, and nearly odorless liquid. It is insoluble in water, soluble in chloroform and slightly soluble in ethanol. It has a molecular weight of 450.70.
Phytonadione is 2-methyl-3-phytyl-1, 4-naphthoquinone. Its empirical formula is C31H46O2 and its structural formula is:
MEPHYTON* (Phytonadione) tablets containing 5 mg of phytonadione are yellow, compressed tablets, scored on one side. Inactive ingredients are acacia, calcium phosphate, colloidal silicon dioxide, lactose, magnesium stearate, starch, and talc.
What are the possible side effects of phytonadione (Mephyton)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
- an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);
- fast or irregular heartbeats; or
- increased sweating.
Call your doctor at once if you have a serious side effect such as:
- feeling like you might pass out;
- blue colored lips; or
- trouble breathing.
Less serious side...
What are the precautions when taking phytonadione (Mephyton)?
Before taking vitamin K, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood disorders, gallbladder disease (e.g., obstructive jaundice, biliary fistula), liver disease.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known whether this medication passes into breast milk. Consult your doctor before...
Last reviewed on RxList: 12/2/2008
This monograph has been modified to include the generic and brand name in many instances.
Additional Mephyton Information
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