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Evidence-Based Supplement Research

Evidence-Based Supplement Research

Vitamin K1 and Reduced International Normalized Ratio

Doses used in studies

mg/day: 2.5 (median 2.5, IQR 2.5–2.5) — 1 study

Time to effect

Median: 7.1 months · IQR 5.1 months–9.2 months · Range 3 months–11.2 months — Reported in 2 of 2 studies

2 of 2 papers

Randomized, placebo-controlled trial of orally administered vitamin K1 for warfarin-associated coagulopathy in Chinese patients with mechanical heart valves.
- 2021-03-30
- RCT · n = 80
- European journal of clinical pharmacology 77(9)
- - Heng Zhang
  - Mei Li
  - Xue-Lian Ao
  - Yi-Jun Dong
  - Li Dong
- PubMed: 33783553
- DOI: 10.1007/s00228-021-03127-8
2 Insights on
- Reduced International Normalized Ratio
- High evidence
- Clinical
Patients administered vitamin K1 exhibited a quick reduction in INR values relative to patients administered placebo (29 of 40 [72.5%] vs. 0 of 44 [0%] patients exhibiting INR values from 1.5-2.5 on the day following treatment, respectively, p = 0.000).
Effect
Beneficial
Effect size
Large
Significant
Yes
Dose
2.5 mg
Effect of vitamin K1 on survival of patients with chronic liver failure: A retrospective cohort study.
- 2020-03
- Observational · n = 80
- Medicine 99(13)
- - Zhuang Xiong
  - Yangyang Liu
  - Tianying Chang
  - Xiaohao Xu
  - Shaokai Huo
  - Houbo Deng
  - Tiejun Liu
  - Yan Leng
- PubMed: 32221088
- DOI: 10.1097/md.0000000000019619
2 Insights on
- Reduced International Normalized Ratio
- Moderate evidence
- Clinical
Vitamin K1 reduced the international normalized ratio levels [P < 0.01 (95% confidence interval 0.000-0.002)].
Effect
Beneficial
Effect size
Moderate
Significant
Yes