BACKGROUND: Muscle cramps are among the common debilitating complications of liver cirrhosis. Since this complication lacks effective treatments, we aimed to evaluate the effectiveness of L-carnitine supplementation in reducing the frequency, duration, and severity of muscle cramps in patients with liver cirrhosis. METHODS: The present retrospective cohort was conducted on adult patients referred between November 2022 and December 2023 to a tertiary referral hospital in Shiraz, Iran. Patients with confirmed liver cirrhosis who had muscle cramps ≥ 4 times per month without other secondary etiologies for muscle cramps were evaluated for inclusion. They were included if they had taken an oral L-carnitine supplement of 1000 mg/day for one month and had available medical records of the assessment of their cramps before and one month after starting the supplement. RESULTS: From the 702 patients screened, 195 (27.8%) had muscle cramps, and 91 (13.0%) met the inclusion criteria. The respective median age and cirrhosis duration (interquartile range (IQR)) of the included patients were 61.0 (16.0) and 2.0 (3.0) years, and 48 (53%) were male. Median daily, weekly, and monthly cramp frequency and severity were higher in females (P-values <
0.05). We noted reduced daily, weekly, and monthly frequency of the cramps, their severity, and their mean duration following L-carnitine supplementation (respective median (IQR) of absolute percentage change: 100 (100.0), 60 (88.33), 50 (75.0), 50 (77.5), and 40.0 (44.58)
P-values <
0.001). Additionally, daily, weekly, and monthly cramps completely resolved in 29 (31.9%), 21 (23.1%), and 13 (14.3%) after supplementation. BMI correlated with the percentage change of all the mentioned cramp indices (P-values <
0.05), and age correlated with the percentage change in the monthly frequency of cramps (P-value = 0.042). Changes in cramp indices did not differ significantly between males and females. CONCLUSIONS: L-carnitine supplementation seems to be a promising therapeutic option for cramps in liver cirrhosis. Further studies with control groups and larger samples are required to confirm this finding.