VAPRISOL IN 5% DEXTROSE IN PLASTIC CONTAINER
Clinical safety rating: caution
Comprehensive clinical and safety monograph for VAPRISOL IN 5% DEXTROSE IN PLASTIC CONTAINER (VAPRISOL IN 5% DEXTROSE IN PLASTIC CONTAINER).
Selective vasopressin V2 receptor antagonist; inhibits water reabsorption in the renal collecting duct, leading to aquaresis.
| Metabolism | Hepatic metabolism primarily via CYP3A4; multiple metabolites including inactive metabolites. |
| Excretion | Renal: 95% as unchanged drug and metabolites; fecal: 5%. |
| Half-life | Terminal half-life: 10-15 hours; prolonged in renal impairment. |
| Protein binding | 99% bound to albumin. |
| Volume of Distribution | 2.0 L/kg; indicates extensive tissue distribution. |
| Bioavailability | IV only; oral bioavailability has not been studied. |
| Onset of Action | IV administration: within 15-30 minutes for increase in serum sodium. |
| Duration of Action | Duration: 24-48 hours; clinical effect correlates with conivaptan plasma levels. |
| Molecular Weight | 362.3 |
IV infusion, initial dose 20 mg once, followed by 20 mg daily if serum sodium increases <5 mEq/L after 24 hours; max 40 mg daily.
| Dosage form | INJECTABLE |
| Renal impairment | Contraindicated in anuria; no dose adjustment for reduced GFR, but monitor renal function. |
| Liver impairment | Mild-to-moderate hepatic impairment (Child-Pugh A or B): no adjustment. Severe (Child-Pugh C): not recommended; use only if benefit outweighs risk. |
| Pediatric use | Safety and efficacy not established; no recommended pediatric dose. |
| Geriatric use | No specific dose adjustment; monitor serum sodium closely due to increased risk of volume depletion or hypernatremia. |
| 1st trimester | Limited human data; animal studies show increased hyponatremia and osmolality effects; use only if potential benefit outweighs risk. |
| 2nd trimester | Same as T1; monitor maternal serum sodium and volume status closely. |
| 3rd trimester | May cause uterine contractions or fetal hyponatremia; avoid in labor unless critically needed. |
Clinical note
Comprehensive clinical and safety monograph for VAPRISOL IN 5% DEXTROSE IN PLASTIC CONTAINER (VAPRISOL IN 5% DEXTROSE IN PLASTIC CONTAINER).
| Placental transfer | Evidence of transfer based on molecular size and animal studies; expected to cross placenta given molecular weight <500 Da. |
| Breastfeeding | Excretion into human milk unknown; due to potential for serious adverse reactions (e.g., hyponatremia), caution advised; consider temporary cessation of breastfeeding during therapy. |
■ FDA Black Box Warning
Initiation and titration should be done in a hospital setting due to risk of overly rapid correction of serum sodium, which can cause osmotic demyelination syndrome.
| Serious Effects |
Hypersensitivity to conivaptan or any componentVolume depletionHypovolemic hyponatremiaConcomitant use with moderate or strong CYP3A inhibitorsAnuriaSevere renal impairment (CrCl <30 mL/min)
| Precautions | Overly rapid correction of hyponatremia (risk of osmotic demyelination syndrome), Monitor serum sodium and neurologic status frequently, Hepatic impairment (dose adjustment required), Renal impairment (avoid in anuria or severe renal impairment) |
| Food/Dietary | No specific food interactions. However, avoid excessive water intake to prevent over-rapid correction of hyponatremia. Maintain a balanced diet as tolerated. |
Loading safety data…
| Lactation Rating | L4 (Limited data – possibly hazardous) |
| Teratogenic Risk | FDA Pregnancy Category C. In animal studies, conivaptan (the active component) caused fetal toxicity (reduced fetal weight, skeletal variations) at doses 0.1-0.5 times the human AUC. No adequate human studies exist. Risk cannot be ruled out; use only if benefit outweighs potential fetal harm. First trimester: theoretical risk due to teratogenic effects observed in animal studies. Second and third trimesters: potential for hyponatremia and volume disturbances in the fetus. |
| Fetal Monitoring | Monitor serum sodium and volume status closely during infusion. Assess neurological status for symptoms of osmotic demyelination syndrome. Monitor maternal blood pressure and heart rate. Fetal monitoring (heart rate, growth) should be considered if used during pregnancy. |
| Fertility Effects | No human data on fertility effects. In animal studies, conivaptan did not affect male or female fertility at doses up to 10 mg/kg/day (approximately 0.5 times human AUC). Theoretical risk of hormonal disturbances due to vasopressin receptor antagonism. |
| Clinical Pearls | Conivaptan is a dual V1A/V2 vasopressin receptor antagonist used for euvolemic or hypervolemic hyponatremia. Correct hyponatremia slowly (≤8-12 mEq/L in 24 hours) to avoid osmotic demyelination syndrome. Monitor serum sodium every 6-8 hours during infusion. Use with caution in patients with heart failure; may cause hypotension. Do not use in hypovolemic hyponatremia. Discontinue if serum sodium exceeds 144 mEq/L or if overly rapid correction occurs. |
| Patient Advice | This medication is given intravenously to raise your blood sodium level. · You will have frequent blood tests to monitor your sodium levels. · Report any signs of confusion, muscle weakness, or difficulty walking, as these may indicate a side effect of rapid sodium correction. · Avoid drinking large amounts of water while on this medicine, as it may lower your sodium too fast. · Tell your doctor if you are pregnant, breastfeeding, or have liver problems. |