| Lamivudine Action Pathway |  | Drug action | Adenosine phosphate / ATP / Lamivudine / Pyrophosphoric acid |
| Lamivudine Metabolism Pathway |  | Drug metabolism | ATP / Lamivudine / Magnesium cation / Uridine-5'-Diphosphate / N,N,N-Trimethyl-2-(phosphonooxy)ethanaminium / Pyrophosphoric acid |
| Lansoprazole Action Pathway |  | Drug action | ATP / Lansoprazole / Potassium cation / Zinc / Acetylcholine |
| Lansoprazole Metabolism Pathway |  | Drug metabolism | Lansoprazole |
| Latrepirdine H1-Antihistamine Action |  | Drug action | Calcium / Latrepirdine |
| Leigh Syndrome |  | Disease | Pyruvic acid / Biotin / Adenosine phosphate / Glutathione / NADH / ATP / Potassium cation / Magnesium cation / Zinc / Phosphoenolpyruvate / Propylene glycol / Acetylphosphate / D-Lactic acid / Flavin adenine dinucleotide / Acetic acid / Pyruvaldehyde / Lactaldehyde / Pyrophosphoric acid / Malonyl-CoA |
| Lepirudin Action Pathway |  | Drug action | Lepirudin / Phylloquinone / Calcium |
| Lesch-Nyhan Syndrome (LNS) |  | Disease | Tetrahydrofolic acid / Aspartic acid / L-Glutamine / Adenosine phosphate / Glutamic acid / Glycine / NADH / ATP / Adenine / Adenosine / Potassium cation / Calcium / Magnesium cation / Zinc / 5-O-phosphono-alpha-D-ribofuranosyl diphosphate / AICA ribonucleotide / Guanosine-5'-Monophosphate / Xanthine / Guanine / Cyclic adenosine monophosphate / Mesoheme / Guanosine / Ribose-1-Phosphate / Flavin adenine dinucleotide / Hypoxanthine / Pyrophosphoric acid / Maleic acid / Inosine / 2'-Deoxyguanosine-5'-Monophosphate |
| Leucine Stimulation on Insulin Signaling |  | Signaling | Leucine |
| Leukotriene C4 Synthesis Deficiency |  | Disease | Glutamic acid / Glutathione / Dinoprostone / Calcium / Magnesium cation / Zinc / Prostaglandin D2 / Mesoheme / Prostaglandin G2 / Arachidonic Acid |
| Levallorphan Action Pathway |  | Drug action | ATP / Norepinephrine / Levallorphan / Dopamine / Potassium cation / Calcium |
| Levobunolol Action Pathway |  | Drug action | ATP / Levobunolol / Potassium cation / Calcium / Magnesium cation |
| Levobupivacaine Action Pathway |  | Drug action | ATP / Norepinephrine / Dopamine / Levobupivacaine / Potassium cation / Calcium |
| Levocabastine H1-Antihistamine Action |  | Drug action | Levocabastine / Calcium |
| Levocetirizine H1-Antihistamine Action |  | Drug action | Calcium / Levocetirizine |
| Levomethadyl Acetate Action Action Pathway |  | Drug action | ATP / Norepinephrine / Dopamine / Levacetylmethadol / Potassium cation / Calcium |
| Levomethadyl Acetate Metabolism Pathway |  | Drug metabolism | NADH / Levacetylmethadol / Mesoheme / Formaldehyde |
| Levorphanol Action Pathway |  | Drug action | ATP / Norepinephrine / Levorphanol / Dopamine / Potassium cation / Calcium |
| Lidocaine (Antiarrhythmic) Action Pathway |  | Drug action | NADH / ATP / Lidocaine / Potassium cation / Calcium / Magnesium cation / Mesoheme / Formaldehyde |
| Lidocaine (Local Anaesthetic) Action Pathway |  | Drug action | NADH / ATP / Lidocaine / Norepinephrine / Dopamine / Potassium cation / Calcium / Mesoheme / Formaldehyde |
| Lidocaine (Local Anaesthetic) Metabolism Pathway |  | Drug metabolism | NADH / Lidocaine / Mesoheme / Formaldehyde |
| Lincomycin Action Pathway |  | Drug action | Histidine / Adenosine phosphate / Methionine / Leucine / Threonine / Alanine / Valine / Isoleucine / ATP / Proline / Asparagine / Lincomycin / Guanosine-5'-Monophosphate / Cytidine-5'-Triphosphate / Uridine monophosphate / D-Serine / Pyrophosphoric acid |
| Lisinopril Action Pathway |  | Drug action | Lisinopril / Zinc |
| Long Chain Acyl-CoA Dehydrogenase Deficiency (LCAD) |  | Disease | Adenosine phosphate / NADH / ATP / Levocarnitine / Magnesium cation / Flavin adenine dinucleotide / Palmitic Acid / Pyrophosphoric acid |
| Long-Chain-3-Hydroxyacyl-CoA Dehydrogenase Deficiency (LCHAD) |  | Disease | NADH / Palmitic Acid |