Granisetron (Intravenous)

Granisetron blocks a pathway in the brain that causes sick, nauseous feelings and prevents vomiting experienced by patients undergoing radiation or chemotherapy treatments for cancer.


What is Granisetron?

Sold under the trade name Kytril, Granisetron is a medication that doctors and other health care professionals administer to patients undergoing cancer treatment with radiation and/or chemotherapy. These patients often have symptoms of nausea which lead to vomiting and a general feeling of illness. Medications such as Granisetron can offer some relief to these conditions, enabling the patient to take nourishment on a more normal basis, which helps their bodies to be strong enough to continue treatment.

How does Granisetron work?

Granisetron is effective because it stops certain chemicals in the body that are the cause of vomiting, nausea and general malaise. Typically given thirty minutes prior to cancer treatment in some patients, Granisetron specifically works on serotonin 5-HT3, which triggers stomach upset, throwing up and other ill feelings in the body. Granisetron is available in oral tablet, skin patch and, as discussed here, intravenous format. Granisetron is known for its extended effectiveness, lasting four to nine hours or more in some patients.

The main effect of Granisetron, however, ultimately comes down to the nerve in the brain that triggers the vomiting activity known as the vagus nerve. Through the serotonin blocking, this nerve is calmed and nausea is abated.

Why do cancer patients experience nausea?

Nausea is a sick feeling that happens to many cancer patients and can lead to vomiting, dizziness, feeling faint or having too fast of a heart rhythm. Studies have shown that vomiting and nausea are caused in a certain portion of the brain that is triggered by use of chemotherapy drugs. Areas of the stomach, intestines and esophagus may also cause nausea after being triggered by chemo. Blocking this portion of the brain with drugs such as Granisetron stops this trigger from happening, easing these symptoms, which are two of the most common, most dreaded symptoms that cancer patients face.

Treating nausea and vomiting with drugs such as Granisetron enables the patient to get proper nutrition into their bodies and also prevents dehydration from occurring. If patients cannot keep down fluids or take the medications they need, it directly affects the success of their treatment. Granisetron prevents and calms the nausea experienced so frequently during treatment.

Conditions Treated

  • Nausea, vomiting due to chemotherapy treatment
  • Nausea, vomiting due to radiation treatment
  • Nausea, vomiting due to surgery

Type Of Medicine

  • Receptor Antagonist

Side Effects

Though Granisetron is tolerated well by the body, there are some instances of unwanted symptoms and effects reported by certain patients. If the following ill feelings occur while you are taking Granisetron, notify your physician right away:

  • Vision changes or blurriness
  • Elevated body temperature
  • Nervous demeanor
  • Ear pounding
  • Rapid or too slow heart rhythm
  • Pain in jaw, back or arm
  • Discomfort or pain in chest
  • Heavy, tight feeling in chest
  • Confused demeanor
  • Dizzy, faint, lightheaded feeling when rising
  • Passing out
  • Irregular heart rhythm
  • Nausea
  • Gasping for breath
  • Rash on skin or itching and hives
  • Sweating

Other adverse effects may occur that are generally short term in nature and disappear after you get used to the treatment. Let your cancer care team know if you're experiencing any of these symptoms so that they can advise you on ways to eliminate them or make them easier to live with:

Side effects other than those mentioned may also happen in some patients. Report any unusual health matters to your cancer care team right away.


Granisetron is administered through intravenous means and only by trained medical professionals such as a doctor or nurse. You will be provided with a patient information leaflet that you should read and make sure you understand prior to being treated with this drug. Ask your doctor any questions prior to your treatment to be absolutely clear on how Granisetron will affect you.

Surgery patients

Granisetron will be administered to you just prior to your anesthesia for your operation and repeated after your procedure is through if necessary. In adult patients, 1 micrograin per kilogram of body weight every thirty seconds will be administered through a needle in your arm. Pediatric patients are not typically given Granisetron during surgical interventions.

Chemotherapy patients

Granisetron will be administered to adult patients thirty minutes prior to your chemotherapy treatment in the amount of 10 micrograins per kilogram of body weight every five minutes through a needle in your arm. Pediatric patients from two to sixteen years of age will have this same dosage. Children younger than two should not receive Granisetron as an anti-nausea drug.


If, in the past, you have experience reactions to a medication, food or even artificial dyes or preservatives, you should let your physician know as this could indicate a risk of allergy to Granisetron as well. If you are on other medications, you should also disclose their details to your cancer treatment team, being sure to include over-the-counter, herbal and vitamin therapies as well.

While Granisetron has been proven effective and safe for some pediatric patients, those younger than two years old should not be considered for treatment with this medication as no data has been provided for this age group. Granisetron has not been studied with regard to effectiveness or safety in pediatric patients of any age with regard to nausea and vomiting after surgery.

Geriatric patients have not been studied enough to provide reliable data on the effectiveness or safety with regard to any age-related issues in this age group. The same risks and rewards of using Granisetron will apply to this group as to the adult group of patients

No data has been provided on the study of the usefulness or safety of Granisetron on women who are pregnant or those who are breastfeeding. Discuss your treatment options with your physician if you are in one of these groups.

Granisetron has been known to react adversely with the following drugs. If you are taking any of these drugs, make them known to your doctor before taking Granisetron:

  • Amifampridine
  • Apomorphine
  • Amisulpride
  • Cisapride
  • Bepridil
  • Fluconazole
  • Dronedarone
  • Pimozide
  • Mesoridazine
  • Saquinavir
  • Piperaquine
  • Terfenadine
  • Sparfloxacin
  • Ziprasidone
  • Thioridazine

Though not a typically recommended combination therapy, the following drugs are to be used with caution while taking Granisetron. Your doctor will want to know prior to your prescribed dose if you are taking:

  • Almotriptan
  • Alfuzosin
  • Amiodarone
  • Amineptine
  • Amitriptylinoxide
  • Amitriptyline
  • Anagrelide
  • Amoxapine
  • Arsenic Trioxide
  • Aripiprazole
  • Astemizole
  • Asenapine
  • Brompheniramine
  • Azithromycin
  • Buserelin
  • Buprenorphine
  • Carbamazepine
  • Buspirone
  • Chlorpheniramine
  • Chloroquine
  • Ciprofloxacin
  • Chlorpromazine
  • Clarithromycin
  • Citalopram
  • Clozapine
  • Clomipramine
  • Crizotinib
  • Cocaine
  • Dabrafenib
  • Cyclobenzaprine
  • Degarelix
  • Dasatinib
  • Desipramine
  • Delamanid
  • Desvenlafaxine
  • Deslorelin
  • Dibenzepin
  • Dextromethorphan
  • Dofetilide
  • Disopyramide
  • Domperidone
  • Dolasetron
  • Doxepin
  • Donepezil
  • Duloxetine
  • Droperidol
  • Eletriptan
  • Efavirenz
  • Escitalopram
  • Erythromycin
  • Fingolimod
  • Fentanyl
  • Fluoxetine
  • Flecainide
  • Frovatriptan
  • Fluvoxamine
  • Gatifloxacin
  • Furazolidone
  • Gonadorelin
  • Gemifloxacin
  • Halofantrine
  • Goserelin
  • Histrelin
  • Haloperidol
  • Hydroxytryptophan
  • Hydroxychloroquine
  • Ibutilide
  • Hydroxyzine
  • Imipramine
  • Iloperidone
  • Isocarboxazid
  • Iproniazid
  • Ketoconazole
  • Ivabradine
  • Leuprolide
  • Lapatinib
  • Levomilnacipran
  • Levofloxacin
  • Lithium
  • Linezolid
  • Lopinavir
  • Lofepramine
  • Lumefantrine
  • Lorcaserin
  • Melitracen
  • Mefloquine
  • Methadone
  • Meperidine
  • Metronidazole
  • Methylene Blue
  • Milnacipran
  • Mifepristone
  • Moclobemide
  • Mirtazapine
  • Nafarelin
  • Moxifloxacin
  • Nefazodone
  • Naratriptan
  • Nilotinib
  • Nialamide
  • Nortriptyline
  • Norfloxacin
  • Ofloxacin
  • Octreotide
  • Opipramol
  • Ondansetron
  • Paliperidone
  • Oxycodone
  • Paroxetine
  • Panobinostat
  • Pazopanib
  • Pasireotide
  • Perflutren Lipid Microsphere
  • Pentazocine
  • Pimavanserin
  • Phenelzine
  • Posaconazole
  • Pitolisant
  • Procarbazine
  • Procainamide
  • Promethazine
  • Prochlorperazine
  • Protriptyline
  • Propafenone
  • Quetiapine
  • Quinine
  • Quinidine
  • Rizatriptan
  • Ranolazine
  • Selegiline
  • Rasagiline
  • Sevoflurane
  • Salmeterol
  • Sodium Phosphate
  • Sertraline
  • Sodium Phosphate, Dibasic
  • Sibutramine
  • Solifenacin
  • Sodium Phosphate, Monobasic
  • Sotalol
  • Sorafenib
  • Sulpiride
  • St John's Wort
  • Sunitinib
  • Sumatriptan
  • Tapentadol
  • Tacrolimus
  • Telithromycin
  • Telavancin
  • Tianeptine
  • Tetrabenazine
  • Tramadol
  • Toremifene
  • Trazodone
  • Tranylcypromine
  • Trimipramine
  • Trifluoperazine
  • Tryptophan
  • Triptorelin
  • Vardenafil
  • Vandetanib
  • Venlafaxine
  • Vemurafenib
  • Vinflunine
  • Vilazodone
  • Vortioxetine
  • Voriconazole
  • Zuclopenthixol
  • Zolmitriptan

Phenobarbital use with Granisetron may cause certain ill health effects to be magnified. Use of these two drugs together may require prescription dosage or frequency changes by your cancer care team.

Consult your doctor on whether you should be eating prior to your treatment or if you should fast. Use of tobacco products or consumption of alcoholic beverages should also be discussed with your physician before you are treated with Granisetron.

Some pre-existing medical conditions can also limit the effectiveness or cause a high risk situation for unwanted side effects. Use of Granisetron may also make certain illnesses worse, depending on what they are. For this reason, it is advised that you disclose your full medical history to your cancer treatment specialist physician before being given a dose of Granisetron. Your doctor will specifically want to know if you suffer from the following conditions currently or have in the past had:

  • Prior hypersensitivity to Granisetron or any medications like it such as alosetron, dolasetron, palonosetron or ondansetron
  • Blockage of the bowel
  • Enlarged abdomen
  • Imbalance of electrolytes
  • Long QT syndrome
  • Heart disease or problems with rhythm


After you leave the hospital with your treatment completed, notify your doctor if you still have vomiting caused by nausea.

Anaphylaxis, a life-threatening hypersensitivity to Granisetron, is a high risk after treatment with this drug. Notify your team of cancer care professionals if you have a skin rash that itches, lightheaded, dizzy feeling, difficulty breathing or swallowing or any swelling of your mouth, face or hands after treatment.

If your stomach feels swollen after your treatment, you may be experiencing a bowel or stomach problem related to the administration of Granisetron. Notify your doctor immediately of any swollen, bloated feeling in your stomach.

Granisetron may change your heart rhythm, which can affect your health in an adverse way especially if you already have heart rhythm issues. Contact your physician right away if you experience a pounding, rapid or uneven heart rhythm.

This medication is not recommended for use in pediatric patients under 2 years old and one of the reasons is that the benzyl alcohol it contains may cause a serious reaction. If your physician has prescribed this for your child under two years old, discuss this risk with them.

Other medications should be avoided during your treatment with Granisetron unless specifically prescribed by your physician. This includes any medications that can be purchased without a prescription or herbal, vitamin or holistic supplements found at the health food store.


Granisetron intravenous medication is stored and administered in a hospital or other professional medical setting by trained personnel. The manufacturer recommends that Granisetron should be stored in the original packaging at room temperature, well away from light, moisture or heat exposure. Expired Granisetron or unused doses of this medication should be disposed of per the manufacturer's instructions and under advisement of local safety laws.


Granisetron is an intravenous anti-nausea medication that is administered by doctors or nurses to cancer patients and those who are about to have surgery to prevent vomiting and the associated ill feeling caused by chemotherapy and other treatments. Working to block the level of an enzyme found in the body called serotonin 5HT3, which stimulates the nerve in the brain that causes vomiting and nausea, Granisetron is considered to be a receptor antagonist medication. Granisetron is sold under the trade name Kytril, which patients may be more familiar with.

Granisetron can be administered through an intravenous system installed in your hand or arm about 30 minutes prior to chemotherapy or 5 minutes prior to your surgical procedure. Patients typically experience four to six hour of nausea relief with Granisetron intravenous medication.

Though tolerated extremely well, Granisetron may cause adverse health symptoms like headache, stomach upset, heartburn, constipation or insomnia. Patients who are being treated with Granisetron are urged to notify their physician if they experience any severe or prolonged unwanted effects of this drug. Patients should disclose their full medical histories including any prescription, over-the-counter, herbal or vitamin supplements they take for any reason. Granisetron may interact with many other drugs in a negative way. Check the leaflet provided to you with your treatment information prior to taking Granisetron.

Granisetron has been known to affect the rhythm of the heart and, for this reason, it is urged that patients who have heart rhythm irregularities communicate these conditions to their health care provider prior to being given a prescription dose of Granisetron. Alert your physician if you have any symptoms such as skin rash, difficulty breathing or swallowing or swelling.