Comparative Pharmacology
Head-to-head clinical analysis: IONSYS versus OXYCONTIN.
Head-to-head clinical analysis: IONSYS versus OXYCONTIN.
IONSYS vs OXYCONTIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
IONSYS is an iontophoretic delivery system for fentanyl, a mu-opioid receptor agonist. Fentanyl binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception and emotional response.
Oxycodone is a full opioid agonist with relative selectivity for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of oxycodone is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with oxycodone. Clinically, dosage is titrated to provide adequate analgesia and may be limited by adverse reactions, including respiratory and CNS depression.
Apply one 40 mcg fentanyl iontophoretic transdermal system to skin on upper arm or chest; delivers 40 mcg per dose on-demand for up to 24 hours or 80 doses, whichever is shorter. Maximum 2 doses per hour, 6 doses per application. Patient must be opioid-tolerant.
10 mg orally every 12 hours; titrate based on pain severity and prior opioid exposure.
None Documented
None Documented
Terminal elimination half-life: 16.3 ± 9.1 hours for fentanyl released from IONSYS; accounts for prolonged release from depot and is longer than intravenous fentanyl (3-12 hours).
4.5-5.0 hours (immediate-release); controlled-release OXYCONTIN has an apparent half-life of 4.5-8.7 hours. Terminal half-life is ~3.5-4 hours for immediate-release, reflecting context-sensitive elimination.
Renal: approximately 90% as fentanyl metabolites (mainly norfentanyl) and less than 10% as unchanged drug; fecal: less than 10%.
Primarily renal (90% as metabolites, 10% unchanged). Also biliary/fecal (10%).
Category C
Category C
Opioid Analgesic
Opioid Analgesic