| Baclofen | Central Nervous System Agents | LC/MS/MS | 2-800 ng/mL | Human EDTA Plasma |
| Balsalazide | Gastrointestinal | LC/MS/MS | 1-500 ng/mL | Human Sodium Heparinized Plasma |
| Balsalazide | Gastrointestinal | LC/MS/MS | 1-500 ng/mL | Human EDTA Plasma |
| Benazepril; Benazeprilat | Cardiovascular | LC/MS/MS | 3-1500 ng/mL | Human EDTA Plasma |
| Benserazide | Central Nervous System Agents | LC/MS/MS | 0.4-10 ng/mL | Human EDTA Plasma |
| Benserazide | Central Nervous System Agents | LC/MS/MS | 0.4-10 ng/mL | Dog Plasma |
| Betamethasone | Immunology | LC/MS/MS | 0.5-100 ng/mL | Human EDTA Plasma |
| Betamethasone Acetate | Immunology | LC/MS/MS | 5-500 pg/mL | Human EDTA Plasma |
| Betamethasone Phosphate | Immunology | LC/MS/MS | 2.5 - 500 ng/mL | Human EDTA plasma |
| Betamethasone; Betamethasone Acetate | Immunology | LC/MS/MS | 0.5 - 50 ng/mL | Human EDTA Plasma |
| Bicalutamide | Oncology | LC/MS | 25-1250 ng/mL | Human EDTA Plasma |
| Bisoprolol | Cardiovascular | LC/MS | 0.2-20 ng/mL | Human EDTA Plasma |
| Bivalirudin | Antithrombotic | LC/MS/MS | 5-5000 ng/mL | Human sodium citrate plasma |
| Bromide | Miscellaneous | ICP-MS | 0.5-50µg/mL | Human Sodium Heparinized Plasma |
| Brompheniramine | Respiratory | LC/MS/MS | 100-20000 pg/mL | Human EDTA Plasma |
| Buflomedil | Cardiovascular | HPLC/UV | 50-3000 ng/mL | Human EDTA Plasma |
| Bupivacaine | Pain | LC/MS/MS | 5-500 ng/mL | Rat Plasma |
| Bupivicaine | Pain | LC/MS/MS | 100-5000 ng/mL | Pig Plasma |
| Buprenorphine | Pain | LC/MS/MS | 50-1200 pg/mL | Dog Plasma |
| Buprenorphine;Norbuprenorphine | Pain | LC/MS/MS | 5-400 ng/mL;10-400ng/mL | Human EDTA Plasma |
| Bupropion ; Threohydroxybupropion ; Erythrohydroxybupropion | Central Nervous System Agents | LC/MS/MS | 10-2000 ng/mL | Rat Plasma |
| Bupropion; Hydroxybupropion | Central Nervous System Agents | LC/MS/MS | 5-1000 ng/mL | Rat Plasma |
| Bupropion; Hydroxybupropion | Central Nervous System Agents | LC/MS/MS | 1-200 ng/mL;1-400 ng/mL | Human EDTA Plasma |
| Bupropion; Hydroxybupropion | Central Nervous System Agents | LC/MS/MS | 1-200 ng/mL | Human EDTA Plasma |
| Bupropion; Hydroxybupropion; Erythrohydroxybupropion; Threohydroxybupropion | Central Nervous System Agents | LC/MS/MS | 1-200 ng/mL; 2-800ng/mL ; 1-40 ng/mL; 1-200 ng/mL ; 1-40 ng/mL | Human EDTA Plasma |
| Buspirone | Central Nervous System Agents | LC/MS/MS | 0.5-50 ng/mL | Monkey/Mouse Plasma |
| Buspirone; 1-(2-pyrimidyl) piperazine | Central Nervous System Agents | LC/MS/MS | 1-100 ng/mL | Monkey/Mouse Plasma |
| Butorphanol | Pain | LC/MS/MS | 0.1-3.0 ng/mL | Human Plasma |