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ONSET 8mg injection

Brand: Pharmadic

Prescription Prescription Required

ONSET 8mg injection is composed of Ondansetron

Ondansetron is an antiemetic that is used for treat and preventing nausea and vomiting. It is used to alleviate vomiting and nausea due to stomach disorders, surgery, cancer medicines (chemotherapy), or radiation treatment (radiotherapy). It works by suppressing a natural molecule in the brain called serotonin, which produces nausea and vomiting.


How To Use

  • Ondansetron is dissolved on the tip of the tongue. It is not intended to be swallowed or chewed.
  • Before using Ondansetron, make sure your hands are completely dry.
  • Place the tablet on the tongue, allow it to thoroughly dissolve before swallowing it with saliva.
  • This medicine does not need to be taken with water. It increases your chances of developing a headache.
  • Ondansetron injection must be administered by a doctor or nurse in a healthcare setting.
  • Based on your clinical situation, your doctor will calculate the proper dose of this injection. Any unfavorable side effects should be reported to your doctor as soon as possible.

Expert Advice

  • Take oral forms with or without meals.
  • Use oral syringe to measure oral solution.
  • Contact prescriber if there is constant headache, excessive drowsiness (feeling of being sleepy), fever, numbness (loss of sensation), constipation (difficulty in passing stool), diarrhea (frequent watery stools), and chest pain.

Primary Uses

Nausea and vomiting


This medication is used in the treatment of nausea (feeling like vomiting) and vomiting induced by cytotoxic (damaging to the cells) chemotherapy (use of chemicals to kill cancer cells) and radiotherapy (use of radiation to kill cancer cells). This medication is also used as a prophylactic drug in treatment of post-operative nausea (feeling like vomiting) and vomiting.

Side Effects

Patients administered with this medication may experience constipation (difficulty in passing stool), headache, flushing (temporary reddening of skin), transient rise in liver enzymes, and very rarely a hypersensitivity reaction, anaphylaxis (serious allergic reaction that may cause death), chest pain, hypotension (low blood pressure), bradycardia (slow heart rate), seizures (sudden and uncontrolled disturbance in the brain causing periods of unconsciousness), and visual disturbance.



No evidence of risk has been found. Pregnant females should consult their doctor before using this medicine.


The effect of this medication is not determined in a lactating female, therefore, stay cautious, and consult your doctor before using this medication.


Ondansetron may cause dizziness or drowsiness. Avoid  driving or anything else that requires concentration until you are sure you can do it properly.


People having liver diseases should consult their doctors before taking Ondansetron.


People having Kidney diseases should consult their doctors before taking Ondansetron.


It is not suggested to drink alcohol while taking Ondansetron since it can exacerbate adverse effects like dizziness.


Tell your doctor if you are hypersensitive to Ondansetron or if you have other Allergies/hypersensitivities before taking it. Inactive components in this medicine may result in serious allergies or other complications. For more information, consult your doctor. Inform your doctor of your medical history, particularly of: irregular heart rhythm, liver problems, stomach/intestinal disorders such as past abdominal surgery, ileus, and swelling, before using Ondansetron. Ondansetron has been linked to a heart rhythm disorder (QT prolongation). QT prolongation can induce dangerous (occasionally fatal) irregular or fast heartbeat as well as other symptoms (like fainting and dizziness) that require immediate medical intervention. If you have specific medical problems or are using other medicines that may induce QT prolongation, your chance of QT prolongation could be increased. Before using Ondansetron, inform your doctor about all the medicines you are currently taking, as well as if you have any of these conditions: certain heart problems (heart failure, sluggish pulse, QT prolongation in the ECG), a family history of specific heart problems (QT prolongation in the ECG, sudden cardiac death) etc. Low levels of magnesium and potassium in the blood may potentially increase your risk of having QT prolongation. This risk may rise if you use certain medicines (such as diuretics) or have conditions such as excessive sweating, diarrhea, or vomiting. Consult your doctor about how to use Ondansetron safely. Ondansetron’s adverse effects, particularly QT prolongation, may be more severe in older adults. Aspartame may be included in Ondansetron. Consult your doctor about the safe use of this medicine if you suffer from phenylketonuria (PKU) or any disease that requires you to limit your consumption of aspartame (or phenylalanine).


This medication is contraindicated in a patient that has congenital (present since the time of birth) long QT syndrome (increased risk of irregular heartbeat which can result in fainting; sudden loss of consciousness, drowning; death by suffocation, seizures; sudden and uncontrolled disturbance in the brain causing periods of unconsciousness, and sudden death).


What is ondansetron used for?

Ondansetron is used to prevent nausea (feeling like vomiting) and vomiting caused by cancer chemotherapy (use of chemicals to kill cancer cells), radiation therapy (use of radiation to kill cancer cells), and surgery.

Is ondansetron a narcotic?

This medication is a narcotic (opioid) used to treat nausea and vomiting.

When should you take ondansetron?

If you are taking ondansetron for nausea that occurs with meals, then the standard tablet should be taken half an hour to 1 hour before meals, and the orally disintegrating tablet or oral soluble film can be taken 15 minutes before meals.

How quickly does ondansetron work?

This medication starts working within 1-2 hours.

How often can I take ondansetron for nausea?

Typical dosage for prevention of nausea (feeling like vomiting): 8 mg starting 1–2 hours before radiation, followed by 8-mg doses every 8 hours after that first dose.

What are its precautions?

Correct electrolyte levels before starting therapy, elderly, and patients with heart and tonsil disorders, hepatic (liver) impairment and intestinal obstructions should be cautious.

How to administer this medicine?

This medicine is used orally or intravenously. The injectable form is injected into a vein by a medical professional. However, if you are self-injecting or doing it at home, ensure that you follow the correct procedure and all relevant precautions. The dose is dependent on the age, condition and its severity. The lowest oral dose should be used for the elderly.


Dawaai's intention is to make sure that it's consumers get information that is accurate, reviewed by an expert and error-free. However, the information mentioned here should not be used as a replacement for the advice of a qualified physician. The information given here is for informational purposes only, which may not cover all possible precautions, side effects, contraindications or drug interactions. Consult your doctor and discuss your queries related to any medicine or disease.


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