samsca

SAMSCA should be initiated and re-initiated in a hospital ( 2.1 ) The recommended starting dose is 15 mg once daily. Dosage may be increased at intervals ≥24 hr to 30 mg once daily, and to a maximum of 60 mg once daily as needed to raise serum sodium. ( 2.1 ) 2.1 Recommended Dosage Patients should be in a hospital for initiation and re-initiation of therapy to evaluate the therapeutic response and because too rapid correction of hyponatremia can cause osmotic demyelination resulting in dysarthria, mutism, dysphagia, lethargy, affective changes, spastic quadriparesis, seizures, coma and death. The usual starting dose for SAMSCA is 15 mg administered once daily without regard to meals. Increase the dose to 30 mg once daily, after at least 24 hours, to a maximum of 60 mg once daily, as needed to achieve the desired level of serum sodium. Do not administer SAMSCA for more than 30 days to minimize the risk of liver injury [see Warnings and Precautions (5.2) ]. During initiation and titration, frequently monitor for changes in serum electrolytes and volume. Avoid fluid restriction during the first 24 hours of therapy. Patients receiving SAMSCA should be advised that they can continue ingestion of fluid in response to thirst [see Warnings and Precautions (5.1) ]. 2.2 Drug Withdrawal Following discontinuation from SAMSCA, patients should be advised to resume fluid restriction and…

Most common adverse reactions (≥5% placebo) are thirst, dry mouth, asthenia, constipation, pollakiuria or polyuria, and hyperglycemia ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Otsuka at 1-877-726-7220 or FDA at 1-800-FDA-1088 ( www.fda.gov/medwatch ). 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reactions rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The adverse event information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates. In multiple-dose, placebo-controlled trials, 607 hyponatremic patients (serum sodium <135 mEq/L) were treated with SAMSCA. The mean age of these patients was 62 years; 70% of patients were male and 82% were Caucasian. One hundred eighty-nine (189) tolvaptan-treated patients had a serum sodium <130 mEq/L, and 52 patients had a serum sodium <125 mEq/L. Hyponatremia was attributed to cirrhosis in 17% of patients, heart failure in 68% and SIADH/other in 16%. Of these patients, 223 were treated with the recommended dose titration (15 mg titrated to 60 mg as needed to raise serum sodium). Overall, over 4,000 patients have been treated with oral doses…

SAMSCA is contraindicated in the following conditions: Patients with autosomal dominant polycystic kidney disease (ADPKD) outside of FDA-approved REMS [see Warnings and Precautions (5.2) ] Unable to sense or respond to thirst Hypovolemic hyponatremia Taking strong CYP3A inhibitors [see Warnings and Precautions (5.5) ] Anuria Hypersensitivity (e.g., anaphylactic shock, rash generalized) to tolvaptan or any components of the product [see Adverse Reactions (6) ] Use in patients with autosomal dominant polycystic kidney disease (ADPKD) outside of FDA-approved REMS ( 4 ) Patients who are unable to respond appropriately to thirst ( 4 ) Hypovolemic hyponatremia ( 4 ) Concomitant use of strong CYP3A inhibitors ( 4 ) Anuria ( 4 ) Hypersensitivity ( 4 )

Single oral doses up to 480 mg (8 times the maximum recommended daily dose) and multiple doses up to 300 mg once daily for 5 days have been well tolerated in studies in healthy subjects. There is no specific antidote for tolvaptan intoxication. The signs and symptoms of an acute overdose can be anticipated to be those of excessive pharmacologic effect: a rise in serum sodium concentration, polyuria, thirst, and dehydration/hypovolemia. No mortality was observed in rats or dogs following single oral doses of 2000 mg/kg (maximum feasible dose). A single oral dose of 2000 mg/kg was lethal in mice, and symptoms of toxicity in affected mice included decreased locomotor activity, staggering gait, tremor and hypothermia. In patients with suspected SAMSCA overdosage, assessment of vital signs, electrolyte concentrations, ECG and fluid status are recommended. Continue replacement of water and electrolytes until aquaresis abates. Dialysis may not be effective in removing tolvaptan because of its high binding affinity for human plasma protein (>98%).

U.S. Poison Control: call or text 1-800-222-1222 (free, 24/7). In an emergency call 911. From the FDA label; not medical advice.

Avoid concomitant use with: Moderate CYP3A inhibitors ( 7.1 ) Strong CYP3A inducers ( 7.1 ) V 2 -receptor antagonists ( 7.3 ) Monitor serum potassium during concomitant therapy with ( 7.2 ): Angiotensin receptor blockers Angiotensin converting enzyme inhibitors Potassium sparing diuretics 7.1 CYP3A Inhibitors and Inducers Strong CYP3A Inhibitors Tolvaptan's AUC was 5.4 times as large and C max was 3.5 times as large after co-administration of tolvaptan and 200 mg ketoconazole [see Warnings and Precautions (5.5) and Clinical Pharmacology (12.3) ] . Larger doses of the strong CYP3A inhibitor would be expected to produce larger increases in tolvaptan exposure. Concomitant use of tolvaptan with strong CYP3A inhibitors is contraindicated [see Contraindications (4) ] . Moderate CYP3A Inhibitors A substantial increase in the exposure to tolvaptan would be expected when SAMSCA is co-administered with moderate CYP3A inhibitors. Avoid co-administration of SAMSCA with moderate CYP3A inhibitors [see Warnings and Precautions (5.5) ]. Patients should avoid grapefruit juice beverages while taking SAMSCA [see Clinical Pharmacology (12.3) ] . Strong CYP3A Inducers Co-administration of SAMSCA with strong CYP3A inducers reduces exposure to SAMSCA [see Clinical Pharmacology (12.3) ] . Avoid concomitant use of SAMSCA with strong CYP3A inducers. 7.2 Angiotensin Receptor Blockers, Angiotensin Converting Enzyme Inhibitors and Potassium Sparing Diuretics Although specific interaction studies were not performed, in clinical studies, tolvaptan was used concomitantly with beta-blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors and potassium sparing diuretics. Adverse reactions of hyperkalemia were approximately 1 to 2% higher when tolvaptan was administered with angiotensin receptor blockers, angiotensin converting enzyme inhibitors and potassium sparing diuretics compared to administration of these medications with placebo. Serum potassium levels should be monitored during concomitant drug therapy. 7.3 V 2 -Receptor Agonist As a V 2 -receptor antagonist, tolvaptan may interfere with the V 2 -agonist activity of desmopressin (dDAVP). Avoid concomitant use of SAMSCA with a V 2 -agonist.