Amazon.com: SIRENLABS L Carnitine Elite Burn Liquid Keto Fat Burner and Metabolism Activator Fat Loss Support Keto Friendly Weight Loss Increase Energy Stimulant Free Strawberry Blast 3000mg (32 Servings) : Amazon.com: Ronnie Coleman Signature Series L Carnitine XS 3000 Liquid, Amino Acids Metabolism and Lean Muscle Strength Support, Stimulant Free, Sugar Free, Zero Carbs, Blue Razz, 16 Oz : Health & Household L Carnitine in the Treatment of Psychiatric and Neurological Manifestations: A Systematic Review Did You Know? Some people report a fishy smell after supplementing with L carnitine. This happens because certain gut bacteria convert carnitine to trimethylamine, a malodorous compound found in rotting fish. Did You Know? Some people report a fishy smell after supplementing with L carnitine. This happens because certain gut bacteria convert carnitine to trimethylamine, a malodorous compound found in rotting fish. Urine normally has a slight smell, but some unusual and strong smells may be a sign that something's wrong.