Interventional Medications Used in Biliary Scanning (1,2,7–12,14–16,21)
| Drug | Indication | Dose | Pharmacokinetics | Mechanism of action | Contraindications/cautions | Adverse effects/interactions |
| Sincalide | Gallbladder ejection fraction on biliary scan | 0.02 μg/kg in 10 mL of saline intravenously over 3–5 min | Onset, 5–15 min; peak, 40 min; limited data | Synthetic active portion of cholecystokinin that stimulates gallbladder contraction and relaxes sphincter of Oddi | Contraindicated in known hypersensitivity, intestinal obstruction, and pregnancy (spontaneous abortion); caution with opioids | Abdominal pain, nausea, dizziness, flushing, urge to defecate, and allergic reaction; no documented interactions |
| Morphine | Differentiation of acute and chronic cholecystitis on biliary imaging | 0.04 mg/kg in 10 mL of saline intravenously over 1–2 min (range of 2–4.6 mg); this is subanalgesic dose | Onset, 5 min; peak, 20 min; half-life, 2 h; duration, 20–50 min; 35% plasma protein–bound | Opioid agonist that constricts sphincter of Oddi to increase pressure in common bile duct | Contraindicated in known hypersensitivity, respiratory depression, and coma; caution in renal or liver impairment, pregnancy, seizures, head injuries, asthma, hypotension, hypothyroidism, pheochromocytoma, addiction, and dyspnea | Respiratory depression, hypotension, vomiting, dysphoria, urinary retention, dizziness, sedation, nausea, and constipation; potential interactions with narcotic analgesics, central nervous system depressants, benzodiazepines, and monoamine oxidase inhibitors |
| Phenobarbital | Biliary imaging | 2.5 mg/kg twice daily orally for 5 d before study | Onset orally, 30–60 min; peak, 2–12 h; half-life, 75–120 h; duration, 4 h to 2 d; 5%–60% plasma protein–bound | Increases radiotracer uptake and biliary excretion by inducing hepatic enzymes | Contraindicated in known allergy to phenobarbital and severe respiratory depression; caution in liver, kidney, or lung dysfunction, elderly, children, and acute pain | Sedation, anxiety, respiratory depression, vomiting, dizziness, nausea, headache, and paradoxical excitement; potential interactions with drugs metabolized by liver and central nervous system depressants |
Duration is period of significant or measurable effect. Some adverse effects are more likely when used therapeutically than in single interventional doses.