Kytril

Kytril is a prescription medication used to prevent nausea and vomiting caused by chemotherapy, radiation, or surgery. Kytril belongs to a group of drugs called serotonin 5-HT3 antagonists, which block serotonin, a natural chemical in the body, from causing nausea and vomiting.

This medication comes as an oral (by mouth) solution, oral tablet, and injection. 

The tablet and solution are usually taken once or twice a day. The injection is injected into the vein by a healthcare provider.

Common side effects of the injectable form when used for chemotherapy include headache and constipation and when used for surgery include pain, headache, and fever. Common side effects of the oral forms include headache, constipation, and lack of energy. 

Kytril can cause drowsiness. Do not drive or operate heavy machinery until you know how it affects you.

The brand Kytril is no longer available, but the generic granisetron is available. 

Oral:

Kytril as a solution or tablet is used to prevent nausea and vomiting caused by cancer chemotherapy and radiation therapy. 

Injectable:

The injectable form is used to prevent nausea and vomiting related to chemotherapy and surgery.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Take Kytril exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

Oral:

Cancer Chemotherapy

Injectable:

Cancer Chemotherapy

Serious side effects have been reported with Kytril including:

• severe allergic reactions. Hypersensitivity (allergic) reactions have been reported in patients who are allergic to other selective 5-HT3 receptor antagonists.
• masking symptoms of intestinal blockage. Using Kytril after stomach surgery or chemotherapy may mask the symptoms of an intestinal blockage (abdominal ileus). Kytril is not intended to drain the contents of the stomach. 
• Benzyl alcohol, a component of Kytril 1 mg/mL (an injectable form of Kytril) has been associated with serious adverse reactions and death, particularly in newborn babies (neonates).

Do not take Kytril if you:

• are allergic to Kytril or any inactive ingredient in Kytril
• have long QT syndrome (condition that increases the risk of developing an irregular heartbeat that may cause fainting or sudden death)

Kytril can cause drowsiness. Do not drive or operate heavy machinery until you know how Kytril affects you.

Kytril can cause serious side effects. See "Drug Precautions" section.

Oral:

Common side effects include:

• headache
• constipation
• lack of energy
• diarrhea
• stomach (abdomen) pain
• indigestion

Injectable:

Common side effects when used for chemotherapy include:

• headache
• constipation
• lack of energy
• drowsiness
• diarrhea

Common side effects when used for surgery include:

• pain
• constipation
• condition of low blood cell count (anemia)
• headache
• fever
• abdominal pain
• increase in liver tests
• difficulty falling or staying asleep
• slow heart rate
• dizziness
• increase in white blood cells
• anxiety
• low blood pressure
• diarrhea
• gassy
• infection
• indigestion
• high blood pressure
• bladder infection
• low urine output
• coughing

This is not a complete list of Kytril side effects. Ask your doctor or pharmacist for more information.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

No drug interactions have been listed by the manufacturer. However, you should tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Not all drug interactions are known or reported and new drug interactions are continually being reported.

However, Kytril can theoretically interact with some medications. Especially tell your doctor if you take:

• medications that block a protein in the body (CYPA4) such as some macrolide antibiotics (clarithromycin, telithromycin), some HIV protease inhibitors (indinavir, nelfinavir, ritonavir, saquinavir), some HCV protease inhibitors (boceprevir, telaprevir), some azole antifungals (ketoconazole, itraconazole, posaconazole, voriconazole), conivaptan (Vaprisol), delavirdine (Rescriptor), and nefazodone
• medications that increase the activity of the enzyme CYP3A4 such as carbamazepine (Tegretol, Equetro, Carbatrol), phenobarbital, phenytoin (Dilantin), rifampin, St John's wort, and nimodipine (Nimotop)

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Kytril falls into category B. There are no good studies that have been done in humans with Kytril. But in animal studies, pregnant animals were given this medication, and the babies did not show any medical issues related to this medication.

It is not known if Kytril crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using Kytril.