The Independent Pharmacy
Ondansetron 8mg Tablets

Ondansetron 8mg Tablets

from £10.00
  • Free standard delivery on orders over £40
    Spend £40.00 more for free delivery
  • Fast, discreet delivery

    Delivered in secure, plain packaging on fully tracked delivery from just £2.95

  • 100% UK-based pharmacy

    Our team of doctors and pharmacists, and our support staff, are all UK-based.

  • Free advice and support

    Have a question? Telephone support is always free; Monday - Friday, 9am - 5pm.

  • We're rated 4.9 out of 5

    Based on over 24,000 reviews collected on Google and

About Ondansetron

Ondansetron 8mg tablets belong to a class of medications called antiemetics, specifically serotonin 5-HT3 receptor antagonists. They are commonly used to prevent nausea and vomiting due to a range of causes. Ondansetron works by blocking the action of serotonin, a neurotransmitter involved in triggering nausea and vomiting. This medication can be used to manage nausea and vomiting in patients who have been prescribed GLP-1 treatments during the initiation phase, or after a dose increase, when these symptoms can be at their worst.

  • Suitable for pregnancy?no
  • Suitable for breastfeeding?no
  • Suitable for age:18 years +
  • Maximum per order:1
  • Consultation required?Yes
    This treatment requires an online consultation for review by our medical team. The decision to supply the specific treatment and quantity requested will be based on whether our medical team are satisfied that it will be safe, appropriate, and effective.
  • Generic Treatment?Yes
    This is a generic medicine and manufacturer of the treatment supplied may vary from the treatment image above, depending on availability. Please contact us once you've placed your order if you require a specific brand and we will do our best to accommodate your request.

Ondansetron Summary

Type of medicineAntiemetic (anti-sickness)
Works byBlocking serotonin 5-HT3 receptors
Active ingredientOndansetron
Effective within10-30 minutes
Pack size10 tablets
ManufacturerAlliance Healthcare, Teva, Almus
Use with alcoholAvoid

Ondansetron 8mg tablets Information

  • Can Ondansetron help with nausea and vomiting from GLP-1 injections?

    GLP-1 (glucagon-like peptide-1) agonists are a class of medications used to treat type 2 diabetes by stimulating insulin release and decreasing glucagon secretion in response to elevated blood sugar levels. GLP-1s are more commonly known as their brands names, Wegovy and Mounjaro. Nausea is a common side effect of GLP-1 agonists, especially when treatment is initiated or the dosage is increased.

    If you are experiencing nausea while taking a GLP-1 agonist, it's essential to discuss your symptoms with your healthcare provider. They can provide guidance on the most appropriate management strategies, which may include adjustments to your medication regimen or the addition of supportive therapies, like Ondansetron.

    While Ondansetron is primarily known for its use in preventing nausea and vomiting caused by chemotherapy, radiation therapy, and surgery, it is sometimes used for other types of nausea, including gastrointestinal side effects associated with certain medications, such as GLP-1 agonists.

    Nausea and vomiting from weight loss injections

    Nausea and vomiting are common side effects associated with the use of GLP-1 agonists, a class of medications used to help with weight loss. These gastrointestinal symptoms typically occur, particularly during the initial weeks of treatment or when the dosage is increased. While the exact mechanism behind GLP-1-induced nausea and vomiting isn't fully understood, it's believed to involve the activation of GLP-1 receptors in the brain's area responsible for regulating nausea and vomiting. Despite being bothersome, these side effects usually diminish over time as the body adjusts to the medication. In some cases, dosage adjustments, changes in administration timing, or supportive therapies may help manage these symptoms effectively, ensuring the continued benefits of GLP-1 agonist therapy for diabetes management.

    Other drug therapies for GLP-1 induced nausea and vomiting

    If Ondansetron is not suitable or effective for managing nausea and vomiting, there are several alternative medications and strategies that your healthcare provider may consider:

    Drugs like metoclopramine and prochlorperazine are also effective for managing nausea and vomiting. They work by blocking dopamine receptors in the brain. These medications may cause drowsiness, dizziness, and dry mouth as side effects. Domperidone is a medication used to relieve symptoms of nausea and vomiting, as well it can help with symptoms of bloating if these are bothersome.

      Non-drug therapy for GLP-1 induced nausea and vomiting

      If you're experiencing nausea and vomiting as side effects of GLP-1 agonist therapy for weight loss, there are several alternatives and strategies your healthcare provider may consider to help alleviate these symptoms:

      1. Gradual Dose Titration: Nausea and vomiting are common side effects when initiating GLP-1 agonist therapy or increasing the dosage. Your healthcare provider may recommend a gradual dose titration schedule to help your body adjust to the medication more gradually, potentially reducing the severity of gastrointestinal side effects.
      2. Change in Administration Timing: Taking GLP-1 agonists with meals instead of on an empty stomach or adjusting the timing of administration may help reduce nausea and vomiting. Some individuals find that taking the medication with the largest meal of the day or in the evening before bed can minimize gastrointestinal discomfort.
      3. Switching to a Different GLP-1 Agonist: If nausea and vomiting persist despite dose adjustments and supportive therapies, your healthcare provider may consider switching to a different GLP-1 agonist. Different GLP-1 agonists may have varying side effect profiles, so switching to an alternative medication may help alleviate gastrointestinal symptoms.
      4. Hydration and Dietary Changes: Staying hydrated and making dietary modifications, such as consuming smaller, more frequent meals and avoiding high-fat or spicy foods, may help reduce nausea and vomiting associated with GLP-1 agonist therapy.

      It's important to communicate openly with your healthcare provider about any side effects you experience while taking GLP-1 agonists. They can work with you to identify the most appropriate management strategies to minimize discomfort and optimize your diabetes treatment plan.


    1. How to take Ondansetron 8mg tablets

      • The recommended dose for oral administration is 8 mg to be taken twice daily.

      Swallow the tablet whole: Take the tablet with a full glass of water. Do not crush, chew, or break the tablet before swallowing, as this may affect the way the medication is absorbed by your body.

      Ondansetron can be taken with or without food.

    2. Ondansetron 8mg tablets ingredients

      The active ingredient contained in ondansetron 8mg tablets is: Ondansetron (as the hydrochloride dihydrate)

      Ondansetron 3mg buccal tablets also contain the following inactive ingredients:

      Tablet core: Lactose monohydrate, Microcrystalline cellulose, Maize starch, Magnesium stearate.

      Tablet coat: Hypromellose, Titanium dioxide E171, Macrogol.

    3. Ondansetron 8mg tablets side effects

      Most people will not experience side effects when they take Ondansetron 8mg tablets, however, if you do they can include

      • Fatigue: Feeling tired or lethargic can also occur frequently with the use of ondansetron
      • Constipation: Some individuals may experience difficulty passing stools or infrequent bowel movements while taking ondansetron
      • Headache: This is a common side effect reported by people taking ondansetron

      These side effects are usually mild and may improve as your body adjusts to the medication. However, if any side effect becomes bothersome or persists, it's important to consult your healthcare provider for further guidance.

      If you are concerned about these effects, or if the product affects you in any other way, stop using it and talk to your doctor or pharmacist.

    4. Ondansetron 8mg tablets warnings

      Ondansetron, like many medications, has certain warnings associated with its use. Here are some important warnings and precautions regarding Ondansetron:

      1. Serotonin Syndrome: Ondansetron can increase serotonin levels in the body, potentially leading to serotonin syndrome, a potentially life-threatening condition. This risk is higher when Ondansetron is used in combination with other medications that also increase serotonin levels, such as selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs). Symptoms of serotonin syndrome may include agitation, hallucinations, coma, fast heart rate, changes in blood pressure, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramp, nausea, vomiting, and diarrhoea.
      2. QT Prolongation: Ondansetron has been associated with a rare but potentially serious side effect called QT prolongation, which can lead to an irregular heartbeat (arrhythmia) called torsades de pointes. This risk may be higher in individuals with certain medical conditions, such as electrolyte abnormalities, heart rhythm disorders, or those taking other medications that also prolong the QT interval. It is important to inform your healthcare provider about all medications you are taking and any medical conditions you have before starting Ondansetron.
      3. Hypersensitivity Reactions: Some people may experience allergic or hypersensitivity reactions to Ondansetron, which can manifest as rash, itching, swelling of the face, lips, tongue, or throat (angioedema), difficulty breathing, or other symptoms. Seek medical attention immediately if you experience any signs of a severe allergic reaction.
      4. Use in Patients with Liver Disease: Ondansetron is primarily metabolized by the liver, so caution is advised when prescribing this medication to individuals with severe liver impairment. Dosage adjustments may be necessary in these patients to avoid potential accumulation of the drug.

      It's important to discuss any concerns or questions you have about Ondansetron with your healthcare provider before starting treatment. They can provide personalized guidance based on your medical history and individual risk factors.

      Ondansetron 8mg tablets and other medicines

      • Serotonergic medications: Ondansetron can increase serotonin levels in the brain. Combining it with other serotonergic medications such as selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, and certain migraine medications can increase the risk of serotonin syndrome, a potentially life-threatening condition characterized by symptoms like agitation, hallucinations, rapid heart rate, fever, excessive sweating, shivering, and diarrhoea.
      • Antiarrhythmic medications: Ondansetron may increase the risk of arrhythmias when used with antiarrhythmic medications such as amiodarone, procainamide, sotalol, and others.
      • Medications metabolized by cytochrome P450 enzymes: Ondansetron is primarily metabolized by the liver enzyme cytochrome P450 3A4 (CYP3A4). Drugs that inhibit or induce CYP3A4 can affect the metabolism of Ondansetron, potentially altering its efficacy or increasing the risk of side effects. Examples of such medications include ketoconazole, rifampicin, and certain antiepileptic drugs.

      Always inform your healthcare provider about all medications, supplements, and herbal products you are taking before starting Ondansetron or any new medication. They can evaluate potential interactions and adjust your treatment plan accordingly to ensure your safety and optimise the effectiveness of your medications.

      Please read all packaging and the Patient Information Leaflet before taking any new medicine and inform your doctor of medicines you are taking or intend to take

    Ordering as easy as 1, 2, 3...

    • Find the ideal treatment

      We can provide over 1052 leading medicines to treat over 90 conditions.

    • Get a free consultation

      Our qualified healthcare professionals will assess your condition and needs.

    • Enjoy our speedy delivery

      And when the time comes to re-order, it'll only take a couple of clicks.

    Need something else?

    We stock 1052 treatments for 90 conditions

    Or browse all treatments or conditions

    A customer at the pharmacist looking for medication