PRIALT
Clinical safety rating: caution
Comprehensive clinical and safety monograph for PRIALT (PRIALT).
Selective N-type voltage-gated calcium channel blocker; inhibits calcium influx, reducing nociceptive neurotransmitter release.
| Metabolism | Primarily hydrolyzed by peptidases in the cerebrospinal fluid and central nervous system; not metabolized by CYP450 enzymes. |
| Excretion | Renal excretion of unchanged drug accounts for approximately 60-70% of elimination; biliary/fecal excretion is minimal, less than 20%. |
| Half-life | Terminal elimination half-life is approximately 4-5 hours in patients with normal renal function; prolonged in renal impairment. |
| Protein binding | Approximately 80-90% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Volume of distribution is about 0.3-0.6 L/kg, indicating distribution primarily within extracellular fluid. |
| Bioavailability | Intrathecal administration: Bioavailability is near 100% as direct delivery to CNS; no oral bioavailability due to extensive first-pass metabolism. |
| Onset of Action | Intrathecal administration: Onset of analgesia occurs within 5-15 minutes. |
| Duration of Action | Duration of analgesia is approximately 24 hours after a single intrathecal injection; continuous infusion provides sustained relief. |
Intrathecal: Initial 0.5-1.2 mcg/hr; titrate to 0.5-1.2 mcg/hr increments every 1-2 weeks based on response; max 2.4-4.8 mcg/hr.
| Dosage form | INJECTABLE |
| Renal impairment | CrCl <60 mL/min: Reduce initial dose to 0.5-1.0 mcg/hr; titrate cautiously. CrCl <30 mL/min: Avoid use due to increased risk of toxicity. |
| Liver impairment | Child-Pugh A: No adjustment. Child-Pugh B: Reduce initial dose to 0.5-1.0 mcg/hr. Child-Pugh C: Avoid use. |
| Pediatric use | Not approved for use in pediatric patients; safety and efficacy not established. |
| Geriatric use | Initiate at low end of dosing range (0.5-1.0 mcg/hr) due to age-related renal impairment and increased sensitivity; titrate slowly. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for PRIALT (PRIALT).
| Breastfeeding | No data on excretion in human milk. M/P ratio unknown. Due to potential for serious adverse reactions in nursing infants (including neurologic effects), breastfeeding is not recommended during treatment and for at least 24 hours after discontinuation. |
| Teratogenic Risk | PRIALT (ziconotide) is Pregnancy Category C. Animal studies have shown developmental toxicity (increased embryonic resorptions, decreased fetal weight) at doses producing maternal toxicity. No adequate human studies in pregnant women. Risk cannot be ruled out; use only if potential benefit justifies potential risk to fetus. First trimester: potential for teratogenicity unknown. Second/third trimester: may cause fetal harm if maternal toxicity occurs. |
■ FDA Black Box Warning
Severe neuropsychiatric reactions including hallucinations, cognitive impairment, and mood changes; may require dose reduction or discontinuation.
| Serious Effects |
["Hypersensitivity to ziconotide","Severe psychiatric disorders","Concurrent administration of intrathecal chemotherapy or radiopharmaceuticals"]
| Precautions | ["Severe neuropsychiatric reactions","Potential for neurotoxicity with bolus injections","Increased risk of meningitis with intrathecal administration","Withdrawal syndrome with abrupt discontinuation","Pump malfunction risk"] |
Loading safety data…
| Fetal Monitoring | Monitor maternal vital signs, neurologic status (e.g., dizziness, nystagmus, confusion), and signs of intrathecal granuloma (pain, sensory changes, bowel/bladder dysfunction). Fetal monitoring: consider fetal heart rate monitoring if maternal hypotension or neurologic adverse events occur. No specific fetal monitoring guidelines; assess fetal well-being via ultrasound if indicated. |
| Fertility Effects | No human data. In animal studies, no adverse effects on male or female fertility were observed at doses up to 0.4 mg/kg/day (systemic exposure). However, limited data; possible impact on reproductive function cannot be excluded. |