| Isosorbide Mononitrate Action Pathway |  | Drug Action | Nitric Oxide / Isosorbide mononitrate / Potassium cation / Calcium / Magnesium cation / Pyrophosphoric acid |
| Isosulfan blue Predicted Metabolism Pathway |  | Metabolic | Mesoheme / Isosulfan blue |
| Isothipendyl H1 Antihistamine Smooth Muscle Relaxation Action Pathway |  | Drug Action | Calcium / Magnesium cation / Isothipendyl |
| Isothipendyl H1-Antihistamine Action |  | Drug Action | Calcium / Isothipendyl |
| Isothipendyl H1-Antihistamine Blood Vessel Constriction Action Pathway |  | Drug Action | Arginine / Citrulline / Sapropterin / Nitric Oxide / Calcium / Magnesium cation / Mesoheme / Flavin adenine dinucleotide / Flavin mononucleotide / Isothipendyl |
| Isothipendyl H1-Antihistamine Immune Response Action Pathway |  | Drug Action | Calcium / Isothipendyl |
| Isovaleric Acidemia |  | Disease | Pyridoxal phosphate / Biotin / Succinic acid / Glutamic acid / Pyridoxal / Leucine / NADH / Valine / Isoleucine / ATP / Acetoacetic acid / Oxogluric acid / Flavin adenine dinucleotide / alpha-Ketoisocaproic acid / alpha-Ketoisovalerate / Methylmalonic Acid |
| Isovaleric Acidemia |  | Disease | Pyridoxal phosphate / Biotin / Succinic acid / Glutamic acid / Pyridoxal / Leucine / NADH / Valine / Isoleucine / ATP / Acetoacetic acid / Oxogluric acid / Flavin adenine dinucleotide / alpha-Ketoisocaproic acid / Isovaleric Acid / alpha-Ketoisovalerate / Methylmalonic Acid |
| Isovaleric Aciduria |  | Disease | Pyridoxal phosphate / Biotin / Succinic acid / Glutamic acid / Pyridoxal / Leucine / NADH / Valine / Isoleucine / ATP / Acetoacetic acid / Oxogluric acid / Flavin adenine dinucleotide / alpha-Ketoisocaproic acid / alpha-Ketoisovalerate / Methylmalonic Acid |
| Isovaleric Aciduria |  | Disease | Pyridoxal phosphate / Biotin / Succinic acid / Glutamic acid / Pyridoxal / Leucine / NADH / Valine / Isoleucine / ATP / Acetoacetic acid / Oxogluric acid / Flavin adenine dinucleotide / alpha-Ketoisocaproic acid / alpha-Ketoisovalerate / Methylmalonic Acid |
| Isoxaflutole Drug Metabolism |  | Metabolic | Isoxaflutole |
| Isoxicam Drug Metabolism |  | Metabolic | Isoxicam |
| Isradipine Action Pathway |  | Drug Action | ATP / Isradipine / Potassium cation / Calcium |
| Isradipine Action Pathway (New) |  | Drug Action | ATP / Isradipine / Calcium / Magnesium cation |
| Itraconazole Action Pathway |  | Drug Action | Itraconazole / Formic acid / Mesoheme / Ergosterol |
| Itraconazole Metabolism |  | Metabolic | Itraconazole / Formic acid / Mesoheme |
| Ivacaftor Predicted Metabolism Pathway |  | Metabolic | Mesoheme / Ivacaftor |
| Josamycin Action Pathway |  | Drug Action | Josamycin |
| Joubert Syndrome |  | Disease | ATP / Calcium / Magnesium cation / Inositol |
| Joubert Syndrome |  | Disease | ATP / Calcium / Magnesium cation / Inositol |
| Kanamycin Action Pathway |  | Drug Action | Kanamycin |
| Kanamycin Action Pathway (new) |  | Drug Action | Streptomycin / Kanamycin |
| Kandutsch-Russell Pathway (Cholesterol Biosynthesis) |  | Metabolic | Iron / Formic acid / Mesoheme / Flavin adenine dinucleotide / Flavin mononucleotide / Cholesterol |
| Kappadione Drug Metabolism |  | Metabolic | Kappadione |
| Kava Drug Metabolism |  | Metabolic | Kava |