Tolvaptan
Tolvaptan is a selective vasopressin V2-receptor antagonist used to treat hyponatremia (low blood sodium) and slow kidney cyst growth in autosomal dominant polycystic kidney disease (ADPKD). It works by blocking vasopressin from binding to V2 receptors in the collecting ducts of the kidneys, promoting water excretion without losing electrolytes, thereby raising blood sodium levels.
A V2-receptor antagonist that promotes aquaresis to treat low sodium levels and slow progression of kidney cysts in ADPKD.
This medication carries a boxed (black box) warning — the strongest type of FDA warning. Review the full prescribing information before use.
Key facts at a glance
- ATC
- C03XA01
- RxNorm
- 358257
- Generic
- Tolvaptan
- Class
- atc-c03
- Brands
- Jynarque, Samsca
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 45mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 15mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 15mg once daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
11 groupspregnancy
first trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks
regular fetal monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
second trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks
regular fetal monitoring and ultrasound
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
third trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks
regular fetal monitoring and uterine activity monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
lactation
breastfeedingdiscontinue breastfeeding
do not breastfeed during treatment and for at least 7 days after last dose
monitor infant for dehydration and electrolyte imbalances if exposure occurs
Use of this medication in this population requires careful consideration of risks and benefits.
pediatric_age
children under 12not established
safety and efficacy not established in pediatric patients - use not recommended
no established pediatric dosing guidelines
pediatric_age
adolescents 12 17not established
safety and efficacy not established in pediatric patients - use not recommended
no established pediatric dosing guidelines
geriatric
elderly 65 plusno specific dose adjustment required but start at low end of dosing range
use with caution due to increased susceptibility to adverse effects such as dehydration and hypernatremia
closely monitor renal function, electrolytes, and fluid status
Use with caution and monitor for adverse effects.
renal_impairment
mild to moderateno dose adjustment needed for mild-moderate impairment
use with caution; monitor renal function and electrolytes regularly
monitor serum creatinine and electrolytes frequently
Use with caution and monitor for adverse effects.
renal_impairment
severeavoid use
avoid in patients with anuria - not effective in absence of urine output
Use of this medication in this population requires careful consideration of risks and benefits.
hepatic_impairment
mild to moderateno specific dose adjustment; start at low dose
use with caution; may require dose reduction and close monitoring
monitor liver function tests and electrolytes closely
Use with caution and monitor for adverse effects.
hepatic_impairment
severeavoid use
avoid use in severe hepatic impairment including refractory ascites
not applicable
Use of this medication in this population requires careful consideration of risks and benefits.
Statistics and clinical data
Drug class
Tolvaptan is a selective vasopressin V2 receptor antagonist
FDA approval year
FDA approval for Samsca (hyponatremia)
Common uses
Therapeutic indications for Tolvaptan
Brand names
Commercial brand names for Tolvaptan
Treatment of clinically significant hypervolemic or euvolemic hyponatremia (adults with SIADH, heart failure, or liver cirrhosis); slowing cyst growth and renal function decline in autosomal dominant polycystic kidney disease (ADPKD).
Selectively blocks vasopressin V2 receptors in the renal collecting ducts with 29x greater affinity for V2 over V1a receptors. This prevents water reabsorption, leading to free water excretion (aquaresis) without electrolyte loss, correcting hyponatremia.
Must be initiated and monitored in an inpatient setting for hyponatremia treatment. Patients should drink water freely to avoid dehydration. Liver function tests must be monitored regularly (hepatotoxicity risk). Avoid grapefruit juice. Contraindicated in patients unable to sense or respond to thirst. May cause frequent urination, dry mouth, and fatigue.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy