L Carnitine: Benefits, Uses, and Side Effects Lifespan Research Institute L CARNITINE 350 MG ( L CARNITINE ) 20 HARD GELATIN CAPSULES Does Carnitine Cause Body Odor? Lume Deodorant L carnitine supplements can cause a fishy odor in the breath, sweat, and urine. This is likely due to the formation of trimethylamine (TMA). TMA is also responsible for the pungent smell of CUD Deficiency Primary Carnitine Deficiency L Carnitine: Benefits, Side Effects, And Dosage, Per Dietitians