Ondansetron Kalceks (Ondansetron)

Ondansetron Kalceks is a selective 5‑HT3 receptor antagonist that reduces nausea and vomiting in several clinical settings.

• Chemotherapy‑induced nausea and vomiting: Helps prevent and control CINV by blocking serotonin signals in the chemoreceptor trigger zone.
• Radiation‑induced nausea and vomiting: Reduces the incidence of RINV by antagonising peripheral 5‑HT3 receptors.
• Post‑operative nausea and vomiting: Decreases the frequency of PONV through central 5‑HT3 blockade.
• Hyper‑emesis gravidarum (off‑label use): May allev symptoms when standard therapies are insufficient.
• Nausea due to other causes: Provides symptomatic relief in various situations where serotonin‑mediated nausea occurs.

• Ondansetron selectively blocks the 5‑hydroxy‑tryptamine type 3 (5‑HT3) receptors located in the vagal nerve terminals of the gastrointestinal tract and in the chemoreceptor trigger zone of the brain. By inhibiting serotonin binding at these sites, it prevents the initiation of the vomiting reflex that is triggered by chemotherapy, radiation, surgery, or other emetogenic stimuli.

Common Side Effects

• Headache: mild to moderate intensity.
• Constipation: occasional bowel movement reduction.
• Diarrhoea: transient loose stools.
• Fatigue: general tiredness.
• Dizziness: brief episodes of light‑headedness.
• Injection site pain (if administered parenterally): mild discomfort.

Serious or Rare Side Effects

• QT interval prolongation: may predispose to cardiac arrhythmias.
• Severe allergic reaction: rash, itching, swelling, or anaphylaxis.
• Serotonin syndrome: rare when combined with other serotonergic agents.
• Hepatic dysfunction: elevated liver enzymes.
• Severe constipation or intestinal obstruction.
• Neuroleptic malignant‑like syndrome: extremely rare neurological emergency.

Ondansetron should be used with caution in patients with known cardiac rhythm disorders or electrolyte imbalances.

• Cardiac monitoring: obtain baseline ECG in patients with risk factors for QT prolongation.
• Electrolyte assessment: correct hypokalaemia or hypomagnesemia before therapy.
• Drug‑interaction review: evaluate concurrent serotonergic medications.
• Pregnancy: use only if the potential benefit outweighs the risk.
• Breastfeeding: consider infant exposure; monitor for adverse effects.
• Store at ambient temperature: keep in the original container, protect from moisture and light.

Ondansetron may interact with several drug classes, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Apomatinib?  

-    -   t   -   -  t . Moderate  g  t. -  t. -  t. -  t. -  t.