What are the symptoms of vitamin K1 (phylloquinone) deficiency?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: July 2, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Vitamin K1 (phylloquinone) deficiency primarily manifests as bleeding disorders due to impaired blood clotting, with symptoms including easy bruising, nosebleeds, bleeding gums, and prolonged bleeding after surgery or injury, as supported by studies such as 1 and 1. The most common symptoms of vitamin K1 deficiency include:

  • Easy bruising
  • Nosebleeds
  • Bleeding gums
  • Blood in urine or stool
  • Excessive bleeding from cuts or wounds
  • Prolonged bleeding after surgery or injury In severe cases, patients may experience internal bleeding, including gastrointestinal bleeding or intracranial hemorrhage, which can be life-threatening, as noted in 1. Women might notice heavier menstrual periods, and newborns with vitamin K deficiency can develop vitamin K deficiency bleeding (VKDB), which may cause bleeding into the brain. Vitamin K1 is essential for activating clotting factors II, VII, IX, and X in the liver, as well as proteins C and S that regulate clotting, as discussed in 1 and 1. Without sufficient vitamin K1, these proteins remain inactive, leading to prolonged clotting times and increased bleeding risk. Deficiency is rare in healthy adults with normal diets but more common in those with malabsorption disorders, those taking certain antibiotics, or individuals on long-term parenteral nutrition, as highlighted in 1 and 1. Treatment typically involves vitamin K1 supplementation, with dosages varying based on severity and underlying cause, such as the recommendations outlined in 1 and 1.

From the Research

Symptoms of Vitamin K1 Deficiency

The symptoms of vitamin K1 (phylloquinone) deficiency can be identified through various studies, including:

  • Generalized bleeding tendency 2
  • Noncarboxylated prothrombin (PIVKA-II) determinations, which are a sensitive indicator of vitamin K deficiency 2
  • Abnormal clotting tests, including prolongation of the APTT, PT, and thrombotest 2
  • Bleeding and ecchymosis 3
  • Convulsions 3
  • Feeding intolerance, poor sucking, and vomiting 3
  • Diarrhea 3
  • Jaundice 3
  • Pallor 3
  • Intracranial bleeding, including subdural, intracerebral, subarachnoid, intraventricular, and combination of these 3

Diagnosis and Management

Diagnosing vitamin K1 deficiency can be challenging due to the different forms and half-lives of vitamin K isoforms 4. However, patients with suspected vitamin K1 deficiency-related coagulopathies can be assessed for coagulopathy correction within 1-2 days after receiving vitamin K, either orally or parenterally 4. Vitamin K1 deficiency can be prevented by providing vitamin K prophylaxis to all newborns, and administration of vitamin K (1 mg) at birth can prevent intracranial bleeding and other hemorrhagic manifestations 3.

Risk Factors

Vitamin K1 deficiency can occur at any age, and risk factors include:

  • Warfarin therapy 2, 5
  • Fasting 2
  • Antibiotic therapy 2
  • Malabsorption syndromes 2, 5
  • Exclusive breastfeeding 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Vitamin K deficiency.

The Southeast Asian journal of tropical medicine and public health, 1993

Research

Late-type vitamin K deficiency bleeding: experience from 120 patients.

Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery, 2012

Research

Vitamin K Deficiency: Diagnosis and Management.

Annals of laboratory medicine, 2025

Research

Vitamin K and thrombosis.

Vitamins and hormones, 2008

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.