| Buclizine H1-Antihistamine Blood Vessel Constriction Action Pathway |  | Drug Action | Arginine / Citrulline / Buclizine / Sapropterin / Nitric Oxide / Calcium / Magnesium cation / Mesoheme / Flavin adenine dinucleotide / Flavin mononucleotide |
| Buclizine H1-Antihistamine Immune Response Action Pathway |  | Drug Action | Buclizine / Calcium |
| Budesonide Action Pathway |  | Drug Action | Glutathione / Dinoprostone / Budesonide / Calcium / Prostaglandin D2 / Mesoheme / Prostaglandin G2 / Arachidonic Acid |
| Bumetanide Action Pathway |  | Drug Action | Cysteine / Bumetanide / Potassium cation / Urea |
| Bumetanide Diruretic Action Pathway |  | Drug Action | Bumetanide / Potassium cation |
| Bumetanide Predicted Metabolism Pathway |  | Metabolic | Bumetanide / Mesoheme |
| Bupivacaine Action Pathway |  | Drug Action | ATP / Bupivacaine / Norepinephrine / Dopamine / Potassium cation / Calcium |
| Bupranolol Action Pathway |  | Drug Action | ATP / Calcium / Bupranolol |
| Bupranolol Action Pathway |  | Drug Action | ATP / Potassium cation / Calcium / Bupranolol |
| Buprenorphine Action Pathway |  | Drug Action | ATP / Norepinephrine / Buprenorphine / Dopamine / Potassium cation / Calcium |
| Bupropion Action Pathway |  | Drug Action | Pyridoxal phosphate / Ascorbic acid / Tyrosine / ATP / Norepinephrine / Dopamine / Bupropion / Levodopa / Calcium / Magnesium cation / Iron / Cyclic adenosine monophosphate / Pyrroloquinoline Quinone / Pyrophosphoric acid |
| Bupropion Metabolism |  | Metabolic | Bupropion / Mesoheme |
| Buspirone Predicted Metabolism Pathway |  | Metabolic | Buspirone / Mesoheme |
| Busulfan Action Pathway |  | Drug Action | Busulfan / Guanine |
| Busulfan Drug Metabolism |  | Metabolic | Busulfan |
| Butabarbital Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Butabarbital / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Butabarbital Drug Metabolism |  | Metabolic | Butabarbital |
| Butalbital Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Butalbital / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Butenafine Action Pathway |  | Drug Action | Butenafine / Magnesium cation / Formic acid / Mesoheme / Flavin adenine dinucleotide / Ergosterol / Pyrophosphoric acid / Farnesyl diphosphate |
| Butobarbital Action Pathway |  | Drug Action | Pyridoxal phosphate / Glutamic acid / ATP / Butobarbital / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Butobarbital Predicted Metabolism Pathway |  | Metabolic | Butobarbital / Mesoheme |
| Butoconazole Action Pathway |  | Drug Action | Butoconazole / Formic acid / Mesoheme / Ergosterol |
| Butoconazole Drug Metabolism |  | Metabolic | Butoconazole |
| Butorphanol Opioid Antagonist Action Pathway |  | Drug Action | ATP / Butorphanol / Calcium / Magnesium cation / Cyclic adenosine monophosphate / gamma-Aminobutyric acid / Pyrophosphoric acid |
| Butriptyline H1 Antihistamine Smooth Muscle Relaxation Action Pathway |  | Drug Action | Calcium / Magnesium cation / Butriptyline |