Mephyton Side Effects

Generic name: phytonadione

Medically reviewed by Drugs.com. Last updated on Jun 12, 2025.

Note: This document provides detailed information about Mephyton Side Effects associated with phytonadione. Some dosage forms listed on this page may not apply specifically to the brand name Mephyton.

Applies to phytonadione: oral capsule, oral tablet.

Other dosage forms:

• injection emulsion, injection solution

Precautions

It is very important that your doctor check your progress at regular visits to see if the medicine is working properly and to decide if you should continue to use it. Blood tests are needed to check for unwanted effects.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Mephyton

Along with its needed effects, phytonadione (the active ingredient contained in Mephyton) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking phytonadione:

Incidence not known

• bluish color of the fingernails, lips, skin, palms, or nail beds
• blurred vision
• chest tightness
• confusion
• cough
• difficulty swallowing
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• fast heartbeat
• hives, itching, skin rash
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• rapid and weak pulse
• sweating
• trouble breathing
• unusual tiredness or weakness
• yellow eyes or skin

Other side effects of Mephyton

Some side effects of phytonadione may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

• change in taste
• feeling of warmth
• redness of the face, neck, arms and occasionally, upper chest

See also:

For healthcare professionals

Applies to phytonadione: compounding powder, injectable solution, oral capsule, oral tablet.

General adverse events

The most common adverse events were dermatologic and injection site reactions.^[Ref]

Cardiovascular

• Rare (less than 0.1%): Rapid and weak pulse, hypotension, cyanosis
• Very rare (less than 0.01%): Facial flushing
• Postmarketing reports: Tachycardia, flushing^[Ref]

Hypersensitivity

• Very rare (less than 0.01%): Anaphylactoid reactions (IV route)
• Frequency not reported: Allergic sensitivity, anaphylaxis
• Postmarketing reports: Fatal hypersensitivity reaction^[Ref]

Fatalities and other severe reactions have occurred during or immediately after the parenteral administration of phytonadione. The majority of these reactions have occurred with intravenous administration. These reactions resemble hypersensitivity or anaphylaxis and include shock and cardiac or respiratory arrest. Feelings of uneasiness, flushing, diaphoresis, chest pain, tachycardia, cyanosis, weakness, and dyspnea may precede the cardiopulmonary event. These severe reactions are more likely with, but are not limited to, rapid infusions of undiluted drug.^[Ref]

Gastrointestinal

Gastrointestinal side effects have rarely included 'peculiar' sensations of taste.

Respiratory

• Rare (less than 0.1%): Dyspnea^[Ref]

Other

• Frequency not reported: Death (IV and IM routes)^[Ref]

Dermatologic

• Uncommon (0.1% to 1%): Erythematous, indurated, pruritic plaques
• Rare (less than 0.1%): Profuse sweating, scleroderma-like lesions,
• Very rare (less than 0.01%): Sweating
• Frequency not reported: Erythema perstans-like lesions^[Ref]

Nervous system

• Rare (less than 0.1%): Dizziness
• Very rare (less than 0.01%): Unusual taste
• Postmarketing reports: Dysgeusia^[Ref]

Hepatic

• Rare (less than 0.1%): Hyperbilirubinemia
• Frequency not reported: Jaundice in newborns^[Ref]

Hyperbilirubinemia occurred primarily with doses above those recommended.^[Ref]

Hematologic

• Frequency not reported: Hemolysis in newborns^[Ref]

Local

• Rare (less than 0.1%): Injection site reactions (inflammation, atrophy, necrosis)
• Very rare (less than 0.01%): Venous irritation or phlebitis (IV route)
• Frequency not reported: Pain, swelling, and tenderness at the injection site^[Ref]

Further information

Mephyton side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer