Jinarc (Tolvaptan)
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Jinarc Used For?
Jinarc contains tolvaptan, which belongs to a group of medicines called vasopressin antagonists. It is specifically designed to treat a genetic kidney condition.
Primary Uses
Jinarc is used to treat Autosomal Dominant Polycystic Kidney Disease (ADPKD), a condition that causes cysts to grow in the kidneys, leading to problems due to their size and the space they occupy.
How It Works
Jinarc prevents a hormone called vasopressin from binding to receptors in your kidneys. By blocking vasopressin’s effects, it slows the development of kidney cysts in patients with ADPKD, reduces disease symptoms, and increases urine production.
Age Restrictions: Jinarc is not recommended for children under 18 years or patients older than 55 years, as safety and effectiveness have not been established in these age groups.
How to Take Jinarc
Jinarc must be taken as two different doses every day at specific times to work properly.
Dosage Instructions
Take one higher-dose tablet (45 mg, 60 mg, or 90 mg) in the morning upon waking, at least 30 minutes before food. Take the second, lower-dose tablet (15 mg or 30 mg) exactly 8 hours later. The afternoon dose can be taken with or without food. Dose combinations are: 45 mg + 15 mg, 60 mg + 30 mg, or 90 mg + 30 mg. Your doctor will start with the lowest combination and may increase to find the best tolerable dose for you. Swallow tablets whole without chewing, crushing, or splitting them.
What If You Miss a Dose?
If you miss a dose, take it as soon as you remember on the same day. If it’s almost time for your next dose, skip the missed dose and continue with your regular schedule. Never take a double dose to make up for a missed one.
Important: Never double your dose. Always take tablets whole – do not chew, crush, or split them to ensure you get the complete dose.
Available Tablet Strengths
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- Thirst
- Increased amount and frequency of urination
- Headache
- Constipation, diarrhea, dry mouth, indigestion, decreased appetite
- Fatigue, weakness, dizziness
- Trouble sleeping
- Muscle spasms
- Rash, dry skin, itching
- Painful, swollen joints
Seek immediate medical attention if you experience:
- Difficulty urinating
- Swelling of face, lips, or tongue
- Generalized rash or severe wheezing/breathlessness
- Signs of electrolyte imbalances (dizziness, confusion, weakness, seizures, palpitations)
- Liver problems (nausea, vomiting, fever, tiredness, loss of appetite, abdominal pain, dark urine, jaundice, itching, joint/muscle pain with fever)
Important Warnings
Jinarc can cause serious liver problems and has several important contraindications that must be considered before starting treatment.
Who Should Not Take Jinarc
Do not take Jinarc if you: are allergic to tolvaptan or any ingredients; have raised liver enzymes in your blood; have high sodium levels in blood; don’t realize when you’re thirsty; have kidneys that cannot produce urine; have low blood volume; are pregnant or breastfeeding; are under 18 years old.
Medical Conditions to Discuss
Tell your doctor if you have: liver disease; difficulty urinating or enlarged prostate; high or low blood sodium levels; high potassium levels; diabetes; high blood pressure; dehydration or excessive vomiting/diarrhea/sweating; gout; lactose intolerance; or if you cannot drink enough water or are fluid restricted.
Pregnancy and Breastfeeding
Jinarc must not be taken during pregnancy or breastfeeding. Use reliable contraception while taking Jinarc and continue for one month after stopping treatment. Tell your doctor immediately if you become pregnant while taking this medication.
Liver Problems: Jinarc can cause serious liver problems. Stop taking it immediately and call your doctor if you experience: tiredness, fever, loss of appetite, rash, nausea, itching, right upper stomach pain, yellowing of skin/eyes, vomiting, or dark urine. Regular liver function blood tests are required.
Drug Interactions
Several medications can interfere with Jinarc and affect how it works. Always inform your healthcare providers about all medications you’re taking.
Grapefruit interaction: Do not drink grapefruit juice when taking Jinarc as it can affect how the medication works.
- Antifungal medications (ketoconazole, fluconazole, itraconazole)
- Antibiotics (clarithromycin, erythromycin, ciprofloxacin, rifampicin)
- HIV medications (saquinavir, ritonavir, atazanavir)
- Heart/blood pressure medications (diltiazem, verapamil, digoxin)
- Sodium-containing medications and effervescent tablets
- Immune system medications (cyclosporine)
- Blood thinners (dabigatran)
- Cholesterol medications (rosuvastatin, pitavastatin)
- Arthritis medications (methotrexate, sulfasalazine)
- Diabetes medications (metformin)
- Epilepsy medications (phenytoin, carbamazepine)
- St John’s wort
- Fluid tablets and blood pressure medications
- Desmopressin
Alcohol & Driving
Jinarc can affect your ability to drive safely and may interact with alcohol consumption.
Alcohol
Tell your doctor if you drink alcohol, as this may affect your treatment with Jinarc.
Driving and Operating Machinery
Be careful before driving or using machines until you know how Jinarc affects you. The medication may cause dizziness or sleepiness, particularly at the beginning of treatment. If this happens, do not drive or use tools or machines.
Storage
Keep Jinarc in its original container in a cool, dry place where the temperature stays below 25°C. Store away from moisture, heat, and sunlight – not in bathrooms, near sinks, in cars, or on window sills. Keep out of reach of children, preferably in a locked cupboard at least 1.5 meters above ground. Take expired or unwanted medicine to any pharmacy for safe disposal.
Overdose Information
If you think you have taken too much Jinarc, seek urgent medical attention immediately. In Australia, call the Poisons Information Centre (13 11 26), contact your doctor, or go to the nearest hospital Emergency Department. In New Zealand, call the National Poisons Centre (0800 POISON or 0800 764 766), contact your doctor, or go to accident and emergency. Do this even if you have no symptoms of discomfort or poisoning.
Frequently Asked Questions
Jinarc increases urine production significantly (5-7 liters per day), so it’s crucial to drink plenty of water. Unless your doctor says otherwise, drink plenty of water during the day and 1-2 glasses before bed, even if you don’t feel thirsty. You must also drink water after urinating at night. Always have access to water and drink when thirsty.
Take the morning dose at least 30 minutes before your morning meal. The second daily dose (taken 8 hours later) can be taken with or without food.
Take the missed dose as soon as you remember on the same day. If it’s almost time for your next dose, skip the missed dose and continue with your regular schedule. Never take a double dose to make up for a missed one.
Jinarc can cause serious liver problems, so your doctor will monitor your liver function with blood tests before starting treatment, monthly for the first 18 months, and then every 3 months. This helps detect any liver problems early.
No, do not stop taking Jinarc or change the dosage without checking with your doctor first. Your doctor will carefully monitor you, especially when starting treatment or increasing doses.
Increased thirst and frequent urination are common and expected effects of Jinarc due to increased urine production. Make sure you have access to water and toilets at all times. Drink plenty of fluids, especially during hot weather, exercise, or illness to prevent dehydration.
Jinarc is not recommended for patients older than 55 years, as the effects in this age group have not been proven. Your doctor will determine if this medication is appropriate for you based on your individual circumstances.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.