Therapy
Oral L-carnitine lowers Lp(a) by 9 mg/dL, but intravenous administration does not, a meta-analysis of randomised trials (Sci Rep 2016)
Original title: Impact of L-carnitine on plasma lipoprotein(a) concentrations: A systematic review and meta-analysis of randomized controlled trials
This systematic review and meta-analysis of randomised controlled trials assessed L-carnitine effect on plasma Lp(a), searching literature through 31 January 2015. Overall, L-carnitine supplementation significantly reduced Lp(a) (weighted mean difference -8.82 mg/dL, 95% CI -10.09 to -7.55, P<0.001). By route of administration, oral L-carnitine significantly reduced Lp(a) (weighted mean difference -9.00 mg/dL, 95% CI -10.29 to -7.72, P<0.001), but intravenous L-carnitine did not (weighted mean difference -2.91 mg/dL, 95% CI -10.22 to 4.41, P=0.436). Meta-regression found the effect was independent of dose (P=0.878) and treatment duration (P=0.374). The findings show oral, but not intravenous, L-carnitine significantly lowers Lp(a), suggesting it could be an effective alternative given the limited number of available Lp(a)-targeted drugs, pending outcome trials to confirm its clinical value.
Original abstract
We aimed to assess the impact of L-carnitine on plasma Lp(a) concentrations through systematic review and meta-analysis of available RCTs. The literature search included selected databases up to 31(st) January 2015. Meta-analysis was performed using fixed-effects or random-effect model according to I(2) statistic. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence interval (CI). The meta-analysis showed a significant reduction of Lp(a) levels following L-carnitine supplementation (WMD: -8.82 mg/dL, 95% CI: -10.09, -7.55, p < 0.001). When the studies were categorized according to the route of administration, a significant reduction in plasma Lp(a) concentration was observed with oral (WMD: -9.00 mg/dL, 95% CI: -10.29, -7.72, p < 0.001) but not intravenous L-carnitine (WMD: -2.91 mg/dL, 95% CI: -10.22, 4.41, p = 0.436). The results of the meta-regression analysis showed that the pooled estimate is independent of L-carnitine dose (slope: -0.30; 95% CI: -4.19, 3.59; p = 0.878) and duration of therapy (slope: 0.18; 95% CI: -0.22, 0.59; p = 0.374). In conclusion, the meta-analysis suggests a significant Lp(a) lowering by oral L-carnitine supplementation. Taking into account the limited number of available Lp(a)-targeted drugs, L-carnitine might be an effective alternative to effectively reduce Lp(a). Prospective outcome trials will be required to fully elucidate the clinical value and safety of oral L-carnitine supplementation.
Summary written by lp-a.org from the published abstract; figures as published. Page updated 18 August 2026. Methods.