Cimetidine (other H2 blockers, such as famotidine, ranitidine, or proton pump inhibitors, can also be used but have different dosing) | 20 mg/kg/d orally for 2 d in children or 10–20 mg/kg/d for 2 d in neonates | Inhibits release of 99mTc-pertechnetate by intraluminal cells, thus increasing and prolonging uptake |
Glucagon | 50 μg/kg intravenously 10 min after administration of 99mTc-pertechnetate | Slightly reduces gastric activity of 99mTc-pertechnetate and suppresses peristaltic activity |
Pentagastrin (no longer recommended in United States secondary to side effects) | 6 μg/kg subcutaneously 20–30 min before 99mTc-pertechnetate administration | Increases gastric mucosal uptake of 99mTc-pertechnetate, thus increasing target-to-background ratio |