| Alimemazine H1-Antihistamine Immune Response Action Pathway |  | Drug Action | Alimemazine / Calcium |
| Alirocumab Action Pathway (New) |  | Drug Action | Calcium / Cholesterol / Alirocumab |
| Alkaptonuria |  | Disease | Pyridoxal phosphate / Ademetionine / Ascorbic acid / Aspartic acid / Tyrosine / Glutamic acid / NADH / Sapropterin / Norepinephrine / Epinephrine / Dopamine / Levodopa / Calcium / Magnesium cation / Iron / Zinc / 2-(3,4-Dihydroxyphenyl)Acetic Acid / Acetoacetic acid / Methylamine / 1,2-Dihydroxybenzene / Oxogluric acid / Flavin adenine dinucleotide / Pyrroloquinoline Quinone / Maleic acid / 4-Hydroxyphenylpyruvic acid / Homogentisic acid |
| Allopurinol Action Pathway (New) |  | Drug Action | NADH / Adenine / Allopurinol / Adenosine / Zinc / Uric acid / Xanthine / Guanine / Ribose-1-Phosphate / Flavin adenine dinucleotide / Hypoxanthine / Inosine / Oxypurinol |
| Almitrine Predicted Metabolism Pathway |  | Metabolic | Almitrine / Mesoheme |
| Alogliptin Drug Metabolism |  | Metabolic | Alogliptin |
| Alosetron Predicted Metabolism Pathway |  | Metabolic | Alosetron / Mesoheme |
| Alpha Linolenic Acid and Linoleic Acid Metabolism |  | Metabolic | alpha-Linolenic acid / Daleuton / Icosapent / Calcium / Arachidonic Acid |
| alpha-Arbutin Drug Metabolism |  | Metabolic | alpha-Arbutin |
| Alprazolam Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Alprazolam / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Alprazolam Predicted Metabolism Pathway |  | Metabolic | Alprazolam / Mesoheme |
| Alprenolol Action Pathway |  | Drug Action | ATP / Alprenolol / Potassium cation / Calcium |
| Alprenolol Action Pathway |  | Drug Action | ATP / Alprenolol / Calcium |
| Alprostadil Action Pathway |  | Drug Action | Alprostadil / Calcium / Magnesium cation / Cyclic adenosine monophosphate |
| Alteplase Action Pathway |  | Drug Action | Alteplase / Calcium |
| Alteplase Action Pathway |  | Drug Action | Alteplase / Phylloquinone / Calcium |
| Altretamine Action Pathway |  | Drug Action | Altretamine / Guanine / Mesoheme / Formaldehyde |
| Aluminum acetate Drug Metabolism |  | Metabolic | Aluminum acetate |
| Aluminum subacetate Drug Metabolism |  | Metabolic | Aluminum subacetate |
| Aluminum zirconium octachlorohydrex gly Drug Metabolism |  | Metabolic | Aluminum zirconium octachlorohydrex gly |
| Alverine Serotonin Antagonist Action Pathway |  | Drug Action | ATP / Potassium cation / Calcium / Magnesium cation / Alverine / Cyclic adenosine monophosphate |
| Alvimopan Action Pathway |  | Drug Action | ATP / Norepinephrine / Dopamine / Potassium cation / Calcium / Alvimopan |
| Alvimopan Opioid Antagonist Action Pathway |  | Drug Action | ATP / Nitric Oxide / Calcium / Magnesium cation / Cyclic adenosine monophosphate / Acetylcholine / Pyrophosphoric acid / Alvimopan |
| Amantadine Anti-viral Action Pathway |  | Drug Action | Amantadine / Calcium |
| Amantadine NMDA Antagonist Action Pathway |  | Drug Action | L-Glutamine / Glutamic acid / Amantadine / Calcium |