| Latrepirdine H1-Antihistamine Action |  | Drug Action | Calcium / Latrepirdine |
| Lavoltidine H2 Anti-histamine Action Pathway |  | Drug Action | ATP / Potassium cation / Magnesium cation / Zinc / Cyclic adenosine monophosphate / Lavoltidine |
| Ledipasvir Action Pathway |  | Drug Action | Magnesium cation / Zinc / Ledipasvir |
| 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 |
| 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 |
| Lemborexant Drug Metabolism |  | Metabolic | Lemborexant |
| Lenalidomide Predicted Metabolism Pathway |  | Metabolic | Lenalidomide / Mesoheme |
| Lenvatinib Action Pathway |  | Drug Action | Calcium / Lenvatinib |
| Lenvatinib Drug Metabolism |  | Metabolic | Lenvatinib |
| Lepirudin Action Pathway |  | Drug Action | Lepirudin / Phylloquinone / Calcium |
| Lercanidipine Action Pathway |  | Drug Action | ATP / Lercanidipine / Calcium / Magnesium cation |
| 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 / Uric acid / 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 |
| Letermovir Action Pathway |  | Drug Action | Letermovir |
| Letermovir Predicted Metabolism Pathway |  | Metabolic | Mesoheme / Letermovir |
| 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 |
| Levacetylmethadol Opioid Agonist Action Pathway |  | Drug Action | ATP / Levacetylmethadol / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid / Sar9, Met (O2)11-Substance P |
| Levallorphan Action Pathway |  | Drug Action | ATP / Norepinephrine / Levallorphan / Dopamine / Potassium cation / Calcium |
| Levallorphan Action Pathway (New) |  | Drug Action | ATP / Levallorphan / Calcium / Magnesium cation / Cyclic adenosine monophosphate / Pyrophosphoric acid |
| Levamisole Drug Metabolism |  | Metabolic | Levamisole |
| Levamlodipine Action Pathway |  | Drug Action | ATP / Calcium / Magnesium cation / Levamlodipine |
| Levetiracetam Action Pathway (New) |  | Drug Action | L-Glutamine / Levetiracetam / Calcium |
| Levetiracetam Predicted Metabolism Pathway |  | Metabolic | Levetiracetam / Mesoheme |
| Levobunolol Action Pathway |  | Drug Action | ATP / Levobunolol / Potassium cation / Calcium |
| Levobunolol Action Pathway |  | Drug Action | ATP / Levobunolol / Calcium |