Assessing the In Vitro and In Vivo Performance of L Carnitine Loaded Nanoparticles in Combating Obesity Levocarnitine Liv Hospital L carnitine supplements bioavailability is very less and according to some studies it takes 8 to 12 weeks for for loss results, so if you decide to supplement with oral L carnitine do take it in Pharmacokinetics of L Carnitine Clinical Pharmacokinetics Springer Nature Link Pharmacokinetics of L Carnitine Clinical Pharmacokinetics Springer Nature Link