| Ammonia Recycling |  | Metabolic | Pyridoxal phosphate / Tetrahydrofolic acid / Histidine / Pyruvic acid / Biotin / Aspartic acid / L-Glutamine / Adenosine phosphate / Serine / Glutamic acid / Glycine / NADH / ATP / Asparagine / Magnesium cation / trans-urocanic acid / Oxogluric acid / Flavin adenine dinucleotide / Pyrophosphoric acid |
| Ammonium carbonate Drug Metabolism |  | Metabolic | Ammonium carbonate |
| Ammonium lactate Drug Metabolism |  | Metabolic | Ammonium lactate |
| Amobarbital Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Amobarbital / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Amobarbital Predicted Metabolism Pathway |  | Metabolic | Amobarbital / Mesoheme |
| Amodiaquine Action Pathway |  | Drug Action | ATP / Amodiaquine / Mesoheme |
| Amodiaquine Predicted Metabolism Pathway |  | Metabolic | Amodiaquine / Mesoheme |
| Amoxapine SSRI Action Pathway |  | Drug Action | Pyridoxal phosphate / Tryptophan / Sapropterin / Amoxapine / Calcium / Iron / Cyclic adenosine monophosphate / Oxitriptan |
| Amphotericin B Action Pathway |  | Drug Action | Amphotericin B / Ergosterol |
| Amprenavir Action Pathway |  | Drug Action | Amprenavir / Magnesium cation |
| Amprenavir Predicted Metabolism Pathway |  | Metabolic | Amprenavir / Mesoheme |
| Amsacrine Drug Metabolism |  | Metabolic | Amsacrine |
| Amyl Nitrite Drug Metabolism |  | Metabolic | Amyl Nitrite |
| Androgen and Estrogen Metabolism |  | Metabolic | NADH / Testosterone / Estrone / Estradiol / Calcium / Androstenedione / Formic acid / Mesoheme / Uridine-5'-Diphosphate / Estrone sulfate / Prasterone sulfate / 5beta-dihydrotestosterone |
| Androstenedione Metabolism |  | Metabolic | NADH / Testosterone / Estrone / Androstenedione / Androstanedione / Formic acid / Mesoheme / Aetiocholanolone / Uridine-5'-Diphosphate / Etiocholanedione |
| Angiotensin Metabolism |  | Physiological | Potassium cation / Zinc |
| Anidulafungin Action Pathway |  | Drug Action | Anidulafungin |
| Anileridine Action Pathway |  | Drug Action | ATP / Norepinephrine / Anileridine / Dopamine / Potassium cation / Calcium |
| Anileridineb Opioid Agonist Action Pathway |  | Drug Action | ATP / Anileridine / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid / Sar9, Met (O2)11-Substance P |
| Anisotropine methylbromide Drug Metabolism |  | Metabolic | Anisotropine methylbromide |
| Anisotropine Methylbromide M2 GI Tract Relaxation Action Pathway |  | Drug Action | ATP / Anisotropine methylbromide / Potassium cation / Calcium / Magnesium cation / Cyclic adenosine monophosphate |
| Anistreplase Action Pathway |  | Drug Action | Anistreplase / Phylloquinone / Calcium |
| Anistreplase Action Pathway (new) |  | Drug Action | Anistreplase / Calcium |
| Ansuvimab Action Pathway |  | Drug Action | Magnesium cation |
| Antazoline H1 Antihistamine Smooth Muscle Relaxation Action Pathway |  | Drug Action | Calcium / Magnesium cation / Antazoline |