This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug, changing your diet or commencing any course of treatment.
Most important. A change in your diet, medicine, or dosage is likely to be necessary. Promptly consult your doctor or pharmacist.
How the interaction occurs:
Tolvaptan is processed by enzymes in your intestine. Grapefruit juice contains compounds that slow down this process, resulting in more medicine reaching your bloodstream.
What might happen:
The amount of tolvaptan in your blood may increase.If you have just started taking tolvaptan to bring your body's low sodium level to normal, this may increase the risk of a serious condition called osmotic demyelination syndrome (ODS), which can lead to coma and death.If you take tolvaptan for a genetic kidney disease, higher levels of tolvaptan may cause adverse effects such as dehydration/dizziness, excessive thirst, increased urination, or low blood pressure which could result in a lowering of your kidney function.
What you should do about this interaction:
Contact your healthcare professional (e.g., doctor or pharmacist) for more information. Let your doctor know right away if you experience any symptoms such as: trouble speaking, trouble swallowing or feeling like food/liquid is getting stuck when you swallow, drowsiness, confusion, mood changes, trouble controlling body movements, weakness in the arms and/or legs, seizures, loss of consciousness, heart palpitations, and/or any other new symptoms. Also let your doctor know if you experience vomiting and/or diarrhea and cannot drink normally and/or if you feel dizzy or faint.Your healthcare professionals may be aware of this interaction and may be monitoring you for it. Do not start, stop, or change your medicine or diet before checking with them first.
1.Samsca (tolvaptan) US prescribing information. Otsuka Pharmaceutical Co., Ltd. November, 2012.
2.Jinarc (tolvaptan) Canada prescribing information. Otsuka Pharmaceutical Company Ltd. June 1, 2015.