Ondansetron Hydrochloride Tablet

What is Ondansetron Hydrochloride and how does it work?

Ondansetron Hydrochloride belongs to the class of drugs called 5-HT3 receptor antagonists. This is used to prevent nausea and vomiting that is associated with certain types of cancer chemotherapy and radiation. This is also used to prevent and treat nausea and vomiting that happens after surgery. Ondansetron Hydrochloride works by reducing the effects of a naturally occurring chemical in the body called serotonin. The Food and Drug Administration (FDA) has already approved this medication. 

Ondansetron Hydrochloride is available in different forms; tablets, orally disintegrating tablets, and oral solution. The tablet form has the dosage strengths of 4 mg and 8 mg for oral use. 

How to use Ondansetron Hydrochloride Tablet?

Dosage is based on your medical condition and response to therapy. The dosage for children may also be based on weight and age. You should not take more medication or take it more often than prescribed. 

  • To prevent nausea and vomiting from chemotherapy, take this within 30 minutes before treatment begins. 
  • To prevent nausea and vomiting from radiation treatment, take this in 1 to 2 hours before the start of your treatment. 
  • To prevent nausea and vomiting after surgery, take this 1 hour before the start of surgery. 

You may take each dose of this medication either with or without a meal. However, your doctor may tell you not to eat before chemotherapy or radiation. Take any other doses as directed by your doctor. If you missed a dose, call your doctor right away. Never double a dose to make up for the missed dose. 

What are the side effects of Ondansetron Hydrochloride?

  • Headache
  • Constipation or diarrhea 
  • Unusually weak or tired
  • Tremors
  • Loss of balance or coordination
  • Light-headedness
  • Dizziness
  • Confusion

Side effects that you need to tell your doctor if it occurs;

  • Breathing problems 
  • Fast or irregular heartbeat
  • Fever and chills 
  • Seizures 
  • Tightness in the chest 
  • Allergic reactions (hives, skin rash, or swelling of the lips, face, or tongue

What medicines may interact with Ondansetron Hydrochloride?

  • Tramadol
  • Rifampicin
  • Phenytoin
  • Linezolid
  • Fentanyl 
  • Carbamazepine
  • MAOIs
  • Certain medicines for anxiety, depression, or psychotic disturbances 

Medicines that you should not take along with Ondansetron Hydrochloride;

  • Ziprasidone
  • Pimozide
  • Cisapride
  • Apomorphine 
  • Dofetilide 
  • Thioridazine 

An interaction between two medicines does not always mean that you must stop taking one of them. Talk with your doctor about how any medicine interactions are being managed or should be managed. 


  • Before you begin with this medication, make sure you tell your doctor about any medical conditions you have or any medications you are taking. 
  • Inform as well your doctor if you are pregnant, breastfeeding, or any other significant facts about your health. These factors may affect how you should use this medication.
  • Seniors may be at an increased risk of developing irregular heartbeat with Ondansetron Hydrochloride. Talk with your doctor about any concerns you may have. 
  • Let your doctor know at once if you are allergic to this drug. This drug contains magnesium, lactose, titanium dioxide, and triacetin as inactive ingredients. The inactive ingredients may cause an allergic reaction. You must tell your doctor if you have any allergies.