Other Less Commonly Used Interventional Medications (57,10,11,1520,23)

DrugIndicationDosePharmacokineticsMechanism of actionContraindications/cautionsAdverse effects/interactions
AcetazolamideCerebral flow reserve in brain perfusion studies1 g diluted in sterile water intravenously over 2 minOnset, 30 min, slow; peak, 2 h; duration, 12 h; half-life, 3–6 h; 70%–90% plasma protein–boundCarbonic anhydrase inhibitor; causes sodium bicarbonate dieresis and vasodilation in brain in response to cerebral carbonic acidosis (carbon dioxide clearance inhibition)Contraindicated in sodium or potassium depletion, hyperchloremic acidosis, Addison disease, closed-angle glaucoma, and severe renal or liver dysfunction; caution in acute stroke, kidney or liver disease, diabetes, gout, lupus, hypotension, and pregnancyTingling sensation, flushing, dizziness, blurred vision, confusion, nausea, headache, tinnitus, and allergic reaction; potential interactions with aspirin, lithium, cyclosporin, amphetamines, other diuretics, antihypertensives, salicylates, hypoglycemics, phenytoin, sodium bicarbonate, anticoagulants, and cardiac glycosides
CimetidineEnhanced detection of Meckel diverticulum300 mg orally, 4 times over 24 h in adults and 20 mg/kg in 20 mL of saline intravenously over 20 min in childrenOnset, 0.5–1 h; peak, 1 h; half-life, 2 h; duration, 4–6 h; 20% plasma protein–boundH2 histamine receptor blocker; reduces gastric acid secretion and volume and impedes 99mTc-pertechnetate secretionContraindicated in known hypersensitivity; caution in renal or cardiovascular dysfunctionHeadache, dizziness, diarrhea, muscle pain, confusion, and bradycardia; potential interactions with medications metabolized in liver; can also alter bioavailability of drugs reliant on stomach pH for absorption
RanitidineAs above300 mg orally for adults and 1 mg/kg intravenously over 20 min for childrenOnset, 60 min; peak, 2–3 h; half-life, 2–3 h; duration, 4–13 h; 15% plasma protein–boundAs aboveAs aboveAs above
Omeprazole40 mg orally morning before and morning of scanOnset, 60 min; peak, 2 h; half-life, 0.5 h; duration, 3–5 d; 95% plasma protein–boundProton pump inhibitor (irreversible); suppresses stomach acid secretion and impedes 99mTc-pertechnetate secretionContraindicated in known hypersensitivity; caution in liver dysfunction; ranitidine is preferred in pediatricsInfrequent but include headache, dizziness, abdominal pain, diarrhea, nausea, vomiting, and rash; potential interactions with diazepam, phenytoin, warfarin, and medications reliant on gastric acidity for absorption
  • Duration is period of significant or measurable effect. Some adverse effects are more likely when used therapeutically than in single interventional doses.