| Rivaroxaban Action Pathway |  | Drug Action | Calcium |
| Rivastigmine Action Pathway (new) |  | Drug Action | Choline / Rivastigmine / Calcium / Magnesium cation / Acetylcholine / Acetic acid |
| Rivastigmine Predicted Metabolism Pathway |  | Metabolic | Rivastigmine / Mesoheme |
| Rizatriptan Mechanism of Action Action Pathway |  | Drug Action | ATP / Rizatriptan / Calcium / Magnesium cation / Cyclic adenosine monophosphate / Pyrophosphoric acid |
| Rofecoxib Action Pathway |  | Drug Action | Glutamic acid / Glutathione / Rofecoxib / Dinoprostone / Calcium / Magnesium cation / Zinc / Prostaglandin D2 / Mesoheme / Prostaglandin G2 / Arachidonic Acid |
| Rolitetracycline Action Pathway |  | Drug Action | Rolitetracycline |
| Rolitetracycline Action Pathway (new) |  | Drug Action | Rolitetracycline |
| Ropinirole Mechanism of Action Action Pathway |  | Drug Action | Pyridoxal phosphate / Tyrosine / Ropinirole / Sapropterin / Dopamine / Levodopa / Calcium / Iron |
| Ropivacaine Action Pathway |  | Drug Action | ATP / Ropivacaine / Norepinephrine / Dopamine / Potassium cation / Calcium |
| Rose bengal I-131 Drug Metabolism |  | Metabolic | Rose bengal I-131 |
| Rosiglitazone Metabolism Pathway |  | Drug Metabolism | NADH / Rosiglitazone / Mesoheme / Formaldehyde |
| Rosuvastatin |  | Drug Action | Rosuvastatin / Calcium / Zinc / Cholesterol |
| Rosuvastatin Action Pathway |  | Drug Action | Cholecalciferol / ATP / Rosuvastatin / Magnesium cation / Iron / Dimethylallyl Diphosphate / Formic acid / Geranyl Diphosphate / Mesoheme / Flavin adenine dinucleotide / Palmitic Acid / Pyrophosphoric acid / Cholesterol / ISOPENTENYL PYROPHOSPHATE / Farnesyl diphosphate |
| Rotigotine Dopamine Agonist Action Pathway |  | Drug Action | Pyridoxal phosphate / Tyrosine / Sapropterin / Dopamine / Levodopa / Calcium / Iron / Rotigotine |
| Roxatidine Acetate Action Pathway |  | Drug Action | ATP / Potassium cation / Zinc / Acetylcholine / Roxatidine acetate |
| Roxatidine Acetate H2 Anti-Histamine Action Pathway |  | Drug Action | ATP / Potassium cation / Magnesium cation / Zinc / Cyclic adenosine monophosphate / Roxatidine acetate |
| Roxithromycin Action Pathway |  | Drug Action | Roxithromycin |
| Roxithromycin Anti=Bacterial Action Pathway |  | Drug Action | Roxithromycin |
| Rufinamide Action Pathway |  | Drug Action | Potassium cation / Calcium / Rufinamide |
| Rupatadine H1 Antihistamine Smooth Muscle Relaxation Action Pathway |  | Drug Action | Calcium / Magnesium cation / Rupatadine |
| Rupatadine H1-Antihistamine Action |  | Drug Action | Calcium / Rupatadine |
| Rupatadine H1-Antihistamine Blood Vessel Constriction Action Pathway |  | Drug Action | Arginine / Citrulline / Sapropterin / Nitric Oxide / Calcium / Magnesium cation / Mesoheme / Flavin adenine dinucleotide / Flavin mononucleotide / Rupatadine |
| Rupatadine H1-Antihistamine Immune Response Action Pathway |  | Drug Action | Calcium / Rupatadine |
| Rupatadine Predicted Metabolism Pathway |  | Metabolic | Mesoheme / Rupatadine |
| Ruxolitinib Mechanism of Action Action Pathway |  | Drug Action | Ruxolitinib |