Tolvaptan

Tolvaptan is used to increase low levels of sodium in the blood in people who have heart or liver disease or certain other conditions. Tolvaptan is in a class of medications called vasopressin V<span class='sub'>2</span> receptor antagonists. It works by increasing the amount of water released from the body as urine. Removing fluid from the body helps to increase the level of sodium in the blood.

Tolvaptan comes as a tablet to take by mouth. It is usually taken once a day with or without food. At the beginning of your treatment, you will be given tolvaptan at a regularly scheduled time in the hospital. If you are told to take tolvaptan at home after you are discharged, you should take it at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take tolvaptan exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Your doctor will probably start you on a low dose of tolvaptan and gradually increase your dose, not more often than once every 24 hours. Talk to your doctor about what you should do after you stop taking tolvaptan. You will probably need to limit the amount of fluid you drink, and your doctor will monitor you carefully during this time.

<p></p> <p></p> <p></p> <p>Tolvaptan may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

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thirst</li>
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dry mouth</li>
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frequent, excessive urination</li>
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nausea</li>
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constipation</li>
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loss of appetite</li>
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fever</li>
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weakness</li></ul></p> <p></p> <p>Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

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vomiting</li>
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diarrhea</li>
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inability to drink normally</li>
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dizziness</li>
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faintness</li>
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vomit that is bloody or looks like coffee grounds</li>
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bloody or black and tarry stools</li></ul>Tolvaptan may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at <a href='http://www.fda.gov/Safety/MedWatch'>http://www.fda.gov/Safety/MedWatch</a>] or by phone [1-800-332-1088].</p>

Before taking tolvaptan, tell your doctor and pharmacist if you are allergic to tolvaptan, any other medications, or any of the ingredients in tolvaptan tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients. tell your doctor if you are taking certain antifungals such as ketoconazole (Nizoral) or itraconazole (Sporanox); clarithromycin (Biaxin); certain medications for HIV such as indinavir (Crixivan), nelfinavir (Viracept), ritonavir (Norvir), or saquinavir (Invirase); nefazodone; or telithromycin (Ketek). Your doctor may tell you not to take tolvaptan if you are taking one or more of these medications. tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: angiotensin-converting enzyme (ACE) inhibitors such as benazepril (Lotensin), captopril (Capoten), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril, (Aceon), quinapril (Accupril), ramipril (Altace), and trandolapril (Mavik); angiotensin II receptor blockers such as candesartan (Atacand), eprosartan (Teveten), irbesartan (Avapro), losartan (Cozaar), olmesartan (Benicar), telmisartan (Micardis), and valsartan (Diovan); aprepitant (Emend); barbiturates such as phenobarbital; carbamazepine (Equetro, Tegretol); cyclosporine (Gengraf, Neoral, Sandimmune); digoxin (Lanoxin); diltiazem (Cardizem, Dilacor, Tiazac); diuretics (water pills); erythromycin (E.E.S., E-Mycin, Erythrocin); fluconazole (Diflucan); phenytoin (Dilantin); potassium supplements; rifabutin (Mycobutin); rifampin (Rimactane, Rifadin); rifapentine (Priftin); and verapamil (Calan, Covera, Isoptin,Verelan). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with tolvaptan, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. tell your doctor what herbal products you are taking or plan to take, especially St John's wort. tell your doctor if you have kidney disease and do not produce urine, if you have severe vomiting or diarrhea, or if you have lost a lot of fluid from your body and feel dizzy or faint. Your doctor will probably tell you not to take tolvaptan. Your doctor will also probably not prescribe tolvaptan if your sodium level must be increased very quickly. tell your doctor if you have or have ever had a high level of potassium in your blood.

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911. Symptoms of overdose may include:

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excessive urination</li>
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excessive thirst</li>
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dizziness</li>
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faintness</li></ul>