Generic Name: tolvaptan (tol-VAP-tan)
Brand Name: Samsca
Tolvaptan should be started or restarted only in a hospital so that blood sodium levels can be closely monitored.
Correcting blood sodium levels too quickly may cause serious and sometimes fatal effects. Patients who have severe liver problems, alcohol abuse or dependence, very poor nutrition, very low blood sodium levels, or syndrome of inappropriate secretion of antidiuretic hormone (SIADH) may have a greater risk. Tell your doctor immediately if you experience confusion, speech problems or loss of speech, trouble swallowing, sluggishness or unusual drowsiness, mental or mood changes, weakness of the arms and legs, trouble controlling body movements, seizures, or loss of consciousness.
Tolvaptan is used for:
Treating low blood sodium levels in certain patients.
Tolvaptan is a selective vasopressin V2-receptor antagonist. It works by increasing fluid excretion from the body, which helps to normalize blood sodium levels.
Do NOT use tolvaptan if:
- you are allergic to any ingredient in tolvaptan
- it is urgent that your blood sodium levels be raised immediately
- you are unable to tell when you are thirsty or you cannot replace fluids by drinking
- you have low blood sodium levels along with low blood or fluid volume
- you are dizzy, you faint, or your kidneys do not work properly because you have lost too much body fluid
- you have liver problems, severe kidney problems, or are unable to urinate
- you are taking aprepitant, clarithromycin, cobicistat, desmopressin, diltiazem, erythromycin, fluconazole, fosaprepitant, itraconazole, ketoconazole, nefazodone, posaconazole, a protease inhibitor (eg, indinavir, nelfinavir, ritonavir, saquinavir), telithromycin, troleandomycin, or verapamil
Contact your doctor or health care provider right away if any of these apply to you.
Before using tolvaptan:
Some medical conditions may interact with tolvaptan. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a history of liver problems (eg, cirrhosis)
- If you have high blood potassium levels, low blood pressure, diabetes, or kidney problems, or if you are on dialysis
- if you are dehydrated or have low blood volume, have very poor nutrition, or have alcohol abuse or dependence
Some MEDICINES MAY INTERACT with tolvaptan. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Angiotensin-converting enzyme (ACE) inhibitors (eg, lisinopril), angiotensin receptor blockers (eg, losartan), potassium-sparing diuretics (eg, triamterene), or other medicines that may increase blood potassium levels because the risk of high blood potassium levels may be increased. Check with your doctor if you are unsure if any of your medicines may increase blood potassium levels
- Aprepitant, azole antifungals (eg, fluconazole, itraconazole, ketoconazole), clarithromycin, cobicistat, cyclosporine, diltiazem , erythromycin, fosaprepitant, nefazodone, protease inhibitors (eg, indinavir, nelfinavir, ritonavir, saquinavir), telithromycin, troleandomycin, or verapamil because they may increase the risk of tolvaptan's side effects
- Carbamazepine, hydantoins (eg, phenytoin), phenobarbital, primidone, rifamycins (eg, rifabutin, rifampin, rifapentine), or St. John's wort because they may decrease tolvaptan's effectiveness
- Digoxin because the risk of its side effects may be increased by tolvaptan
- Desmopressin because its effectiveness may be decreased by tolvaptan
This may not be a complete list of all interactions that may occur. Ask your health care provider if tolvaptan may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use tolvaptan:
Use tolvaptan as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Tolvaptan comes with an extra patient information sheet called a Medication Guide. Read it carefully. Read it again each time you get tolvaptan refilled.
- Take tolvaptan by mouth with or without food.
- Do not eat grapefruit or drink grapefruit juice while you are taking tolvaptan.
- Continue to take tolvaptan even if you feel well. Do not miss any doses.
- If you miss a dose of tolvaptan, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once. If you miss several doses of tolvaptan, contact your doctor for instructions.
Ask your health care provider any questions you may have about how to use tolvaptan.
Important safety information:
- Follow your doctor's instructions regarding fluid intake during treatment with tolvaptan and after you stop taking it.
- Do not stop taking tolvaptan and start taking it again on your own. Tolvaptan should only be restarted in a hospital so that blood sodium levels can be closely monitored. Contact your doctor right away if you stop taking tolvaptan for any reason.
- Do NOT take more than the recommended dose or take for longer than prescribed without checking with your doctor.
- If vomiting or diarrhea occurs, or if you cannot drink normally, you will need to take care not to become dehydrated. Contact your doctor for instructions.
- If you feel dizzy or faint, contact your doctor. This may mean that you have become dehydrated.
- Tolvaptan may cause serious and sometimes fatal liver problems. Do not take tolvaptan for more than 30 days. Tell your doctor if you have a history of liver problems. Contact your doctor right away if you develop symptoms of liver problems (eg, dark urine; pale stools; severe or persistent loss of appetite, nausea, or vomiting; severe stomach pain; severe or unusual tiredness or weakness; unusual itching; yellowing of the eyes or skin).
- Diabetes patients - Tolvaptan may raise your blood sugar. High blood sugar may make you feel confused, drowsy, or thirsty. It can also make you flush, breathe faster, or have a fruit-like breath odor. If these symptoms occur, tell your doctor right away.
- Diabetes patients - Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
- Tell your doctor or dentist that you take tolvaptan before you receive any medical or dental care, emergency care, or surgery.
- Lab tests, including blood sodium levels, liver function, and neurologic tests, may be performed while you use tolvaptan. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Tolvaptan should be used with extreme caution in CHILDREN; safety and effectiveness in children have not been confirmed.
- PREGNANCY and BREAST-FEEDING: If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using tolvaptan while pregnant. It is not known if tolvaptan is found in breast milk. Do not breast-feed while you are taking tolvaptan.
Possible side effects of tolvaptan:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Constipation; decreased appetite; dry mouth; increased thirst; increased urination; nausea; weakness.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); black, bloody, or tarry stools; calf or leg pain, swelling, redness, or tenderness; chest pain; confusion; coughing up blood; dark urine; decreased urination; fainting; fever; irregular heartbeat; mental or mood changes; seizures; severe or persistent dizziness, vomiting, nausea, or diarrhea; severe or unusual muscle pain or weakness; shortness of breath; sluggishness; speech problems or loss of speech; symptoms of high blood sugar (eg, increased hunger, flushing, rapid breathing, fruit-like breath odor); trouble swallowing; uncontrolled muscle movements (eg, in the arms or legs); unusual bruising or bleeding; unusual drowsiness; vision problems; vomit that looks like coffee grounds; weakness in the arms and legs.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of tolvaptan:
Store tolvaptan at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep tolvaptan out of the reach of children and away from pets.
- If you have any questions about tolvaptan, please talk with your doctor, pharmacist, or other health care provider.
- Tolvaptan is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take tolvaptan or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about tolvaptan. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to tolvaptan. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using tolvaptan.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.