Key facts about Samsca
What is Samsca?
Samsca is the brand name for tolvaptan and is available as an oral tablet.
What dosages is Samsca available in?
Samsca is available as a 15 mg and 30 mg oral tablet.
What is Samsca used for?
Samsca is a vasopressin receptor antagonist and is used to treat:
- Low blood sodium levels with a high blood volume (hypervolemic hyponatremia)
- Low blood sodium levels with a normal blood volume (euvolemic hyponatremia)
How does Samsca work?
Samsca is a vasopressin receptor antagonist. It works by blocking a natural hormone in your body called vasopressin from attaching to the vasopressin-2 receptor in your kidneys. When this happens, your kidney doesn’t absorb as much water back into your body and you end up urinating the water out. This causes your blood sodium level to go up.
How do I take Samsca?
The typical starting dose is 15 mg by mouth once per day. Your provider might slowly raise the dose to up to 60 mg once per day, depending on how your blood sodium levels respond to the medication and if you’re having side effects. The maximum duration of treatment is 30 days.
Is it safe for me to take Samsca?
Samsca is a safe and effective treatment when used for FDA licensed indications. However, like all medications, they may give you unwanted side effects. You should always discuss potential side effects with your physician to ensure the medication is suitable and right for you. You should not use this medication if you have any of the following:
- Autosomal dominant polycystic kidney disease (ADPKD) outside of FDA-approved REMS
- Are unable to respond appropriately to thirst
- Hypovolemic hyponatremia
- Concomitant use of strong CYP3A inhibitors
- Anuria
Samsca Common Side Effects
Common side effects of Samsca:
- Feeling thirsty
- Dry mouth
- Urinating more often and more volume
- Lack of energy
- Constipation
- High blood sugar
Samsca Serious Side Effects
Serious side effects are rare with Samsca. Contact your healthcare provider immediately if you experience any of the following.
- Osmotic demyelination syndrome: confusion, problems swallowing, slurred speech, low energy, weakness in face, arms, or legs
- Liver problems or liver failure: yellowing of your skin or the whites of your eyes, confusion, fatigue, poor appetite, nausea, stomach discomfort, vomiting
Losing too much body fluid: dry mouth, dry skin, fast heart rate, dizziness, lightheadedness, feeling tired - High blood potassium levels: tiredness, muscle weakness, tingling or numbness, irregular heartbeat, trouble breathing
Effects of other drugs, drug classes and over-the-counter products on Samsca
The following medications may interact with Samsca: Avoid concomitant use with:
- Moderate CYP3A inhibitors
- Strong CYP3A inducers
- V2-receptor antagonists
Monitor serum potassium during concomitant therapy with:
- Angiotensin receptor blockers
- Angiotensin converting enzyme inhibitors
- Potassium sparing diuretics
Who makes Samsca?
Otsuka Pharmaceutical
Is Samsca safe in pregnancy?
Samsca may cause fetal harm. You should talk to your healthcare provider before taking this medication if you are pregnant.













