Dosing and uses of GastroMark, Primovist (ferumoxsil)
Adult dosage forms and strengths
oral solution
- 175mcg/mL Fe (300mL)
MRI of GI Tract
Used for usually upper GI, limited utility for lower GI/retroperitoneal region
600 mL PO at 300 mL/15 min
No more than 900 mL
Administration
Fast 4 hr before taking
Pediatric dosage forms and strengths
<16 yo: safety/efficacy not established
Warnings
Contraindications
Hypersensitivity
GI perforation or obstruction
Cautions
Hiatal hernia, GERD, nausea/vomiting, abd pain, pts on specific fluid intake, iron overload d/o (eg, hemochromatosis, hemosiderosis, frequent transfusions)
May cause nausea, vomiting, diarrhea, abd cramps
Pregnancy and lactation
Pregnancy category: B
Lactation: iron enters breast milk, not known about other components; use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of GastroMark, Primovist (ferumoxsil)
Absorption: iron is absorbed (depends on iron stores); silicone not known
Excretion: feces
Mechanism of action
Superparamagnetic iron oxide/silicone containing polymer
Fills stomach & small intestine 30-45 min postingestion
Passes thru large intestine 4-7 hr postingestion
