Nocturnal Leg Cramps Treatment: Vitamin K Reduces Frequency, Severity

Among older adults, supplementation with vitamin K₂ may serve as a nocturnal leg cramps treatment by reducing the frequency, intensity, and duration of these cramps. These are the findings of a study published in JAMA Internal Medicine.

In 2022, researchers published data on the safety and efficacy of vitamin K₂ in reducing dialysis-related muscle cramps. Due to lack of safe and effective treatment options for nocturnal leg cramps, the researchers conducted a randomized multicenter double-blind trial (ClinicalTrials.gov Identifier: NCT05547750) to determine the role of vitamin K₂ supplements in the management of nocturnal leg cramps.

Participants aged 65 years and older with at least 2 episodes of unexplained nocturnal leg cramps within a period of 2 weeks were included in the analysis. Eligible participants were randomly assigned 1:1 to receive vitamin K₂ or placebo daily for 8 weeks.

The researchers collected data at baseline and every week on number of nocturnal leg cramp events, duration, and pain severity.

Primary outcome was mean number of nocturnal leg cramps per week. Secondary outcomes were duration (measured in minutes) and severity of muscle cramps, assessed using an analog scale from 1 to 10.

Between 2022 and 2023, 199 (mean age, 72.3; women, 54.3%) of the 310 individuals identified were eligible for the study. Of the total cohort, 103 patients (51.8%) received vitamin K₂ and 96 (48.2%) received placebo. The majority of participants in both groups were compliant with treatment.

Baseline measurements of nocturnal leg cramps were comparable in the vitamin K₂ and placebo groups (2.60 and 2.71, respectively).

After 8 weeks of treatment, patients receiving vitamin K₂ vs placebo had significant reductions in mean nocturnal leg cramp frequency (0.96 vs 3.63, respectively), with the difference in mean nocturnal leg cramp frequency being statistically significant (difference, -2.67; 95% CI, -2.86 to -2.49; P <.001).

 In addition, changes in nocturnal leg cramp events from baseline to the intervention phase in the vitamin K₂ vs placebo groups were significantly different (-1.64 vs 0.92, respectively; P <.001). The duration and severity of nocturnal leg cramps were also decreased in patients receiving vitamin K₂ vs placebo (-0.90 vs -0.32 minutes; -2.55 vs -1.24, respectively).

Overall, no adverse events were reported with vitamin K₂.

Limitations of the analysis included the lack of accounting for quality of life and sleep and that the nocturnal leg cramps were of mild severity.

“This trial suggests that vitamin K₂ might be an effective strategy for managing NLCs [nocturnal leg cramps] in older individuals with good safety profile,” the researchers concluded.

One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures.