Domegan

Domegan is a trade name for a drug whose main active ingredient is ondansetron. Ondansetron belongs to a class of drugs called 5-HT3 serotonin receptor antagonists. It is used to prevent nausea and vomiting caused by various factors.

Ondansetron is often used in the following conditions:

1. Chemotherapy: The drug is used to prevent nausea and vomiting that may occur as a result of chemotherapy treatment.
2. Radiotherapy: It may also be used to reduce nausea and vomiting caused by radiotherapy.
3. After surgery: Ondansetron may be used to prevent nausea and vomiting after surgery.
4. Drug treatment: Ondansetron is sometimes used to treat nausea and vomiting caused by drugs or other medications.

Ondansetron is available as an injection solution.

Before use, it is important to consult with your doctor to determine the best dosage and form of the drug for your individual needs and taking into account the specifics of your disease or treatment.

Indications Domegana

1. Chemotherapy: Domegan is used to prevent nausea and vomiting, which often occur in patients during chemotherapy treatment.
2. Radiotherapy: It may also be used to reduce nausea and vomiting caused by radiotherapy.
3. Postoperative nausea and vomiting: Domegan can be used to prevent and treat nausea and vomiting after surgery.
4. Drug therapy: It is sometimes used to treat nausea and vomiting caused by other medications.
5. Gastroenterological disorders: Domegan can be used for various gastrointestinal disorders such as gastritis, gastroesophageal reflux disease (GERD), gastroenteritis, etc., if accompanied by nausea and vomiting.

Release form

Injection solution: Ondansetron in solution form is used for intravenous and sometimes intramuscular administration. This form is preferred in conditions where a rapid effect is needed, such as to prevent nausea and vomiting after surgery or during chemotherapy.

Pharmacodynamics

Its pharmacodynamics involve interaction with certain receptors in the body, which helps reduce stimulation of the vomiting centers in the brain.

Domegan belongs to a class of drugs known as selective 5-hydroxytryptamine (5-HT3) antagonists. These drugs act on serotonin (5-HT3) receptors, unlike other serotonin antagonists. Ondansetron blocks the action of serotonin at peripheral and central 5-HT3 receptors.

Ondansetron acts primarily in the small intestine and at the brain level, where it reduces the activation of vomiting centers in the brain, such as the nucleus of the vomiting center. This results in a reduction in nausea and vomiting associated with chemotherapy or postoperative conditions.

This mechanism of action makes Domen an effective agent for the control of nausea and vomiting in a variety of clinical situations.

Pharmacokinetics

1. Absorption: Ondansetron is generally well absorbed after oral administration. Peak plasma concentrations are usually reached 1-2 hours after administration.
2. Distribution: Ondansetron has a large volume of distribution, indicating that it is distributed into many tissues of the body. It can cross the placental barrier and is found in breast milk.
3. Plasma protein binding: Ondansetron is limited to plasma proteins, approximately 70-76%.
4. Metabolism: Ondansetron is metabolized in the liver to form several metabolites, including hydroxy-ondansetron and glucuronides. The major metabolic pathway is oxidation via cytochrome P450 enzymes, primarily CYP3A4 and CYP1A2.
5. Elimination: Ondansetron is eliminated from the body primarily via the kidneys. The half-life is approximately 4-6 hours in adults and may be prolonged in elderly patients or those with impaired renal function.

Dosing and administration

For adults:

When receiving chemotherapy, there is a high risk of inducing vomiting:

• Oral: The usual starting dose is 24 mg 30 minutes before the start of chemotherapy.
• Intravenous: 0.15 mg/kg, usually three doses, the first given 30 minutes before chemotherapy and subsequent doses given 4 and 8 hours after the first dose.

For chemotherapy with low or moderate risk of causing vomiting:

• Oral: 8 mg 30 minutes before chemotherapy, then 8 mg every 12 hours for 1 to 2 days after chemotherapy.
• Intravenously: 0.15 mg/kg up to three times daily.

Postoperative nausea and vomiting:

• Oral: 16 mg 1 hour before anesthesia.
• Intravenously: 4 mg immediately before anesthesia.

For children:

During chemotherapy:

• Intravenous: 0.15 mg/kg, maximum three doses, the first administered 30 minutes before chemotherapy, the next 4 and 8 hours after the first.
• Oral: Dosage may vary, but is typically 4 mg 30 minutes before chemotherapy, then doses 4 and 8 hours after the first dose.

Postoperative nausea and vomiting:

• Intravenous or oral: Dosage and route of administration are similar to adults, but taking into account the child's weight and clinical needs.

General recommendations:

• Ondansetron can be taken with or without food.
• It is important to monitor the patient's hydration, especially if vomiting is severe.
• The dosage may be adjusted depending on the individual patient's response and on the doctor's recommendation.

Use Domegana during pregnancy

The use of Domegan during pregnancy may be associated with some risks, so its use requires caution. Key findings from scientific studies:

1. Ondansetron and risk of adverse fetal outcomes: A Danish study found that ondansetron use during pregnancy was not associated with an increased risk of spontaneous abortion, stillbirth, major birth defects, preterm birth, low birth weight, or small for gestational age. This study provides reassuring data that ondansetron may be safe for use during pregnancy (Pasternak et al., 2013).
2. Western Australian study: The study found that ondansetron was given to pregnant women to treat morning sickness and vomiting, and while there was no significant increase in the risk of major birth defects with first trimester exposure, the study could not definitively conclude that ondansetron is safe for use during pregnancy (Colvin et al., 2013).

Overall, these studies suggest that ondansetron can be used during pregnancy if it is clinically warranted and its potential benefits outweigh the possible risks.

Contraindications

1. Allergy to ondansetron or any other component of the drug. Patients with a known hypersensitivity to ondansetron or similar substances (eg, granisetron) should avoid using this drug.
2. Concomitant use with apomorphine. Ondansetron should not be used together with apomorphine, as the combination may cause a significant drop in blood pressure and loss of consciousness.
3. Patients with cardiac conduction disorders such as congenital or acquired prolonged QT interval. Ondansetron may prolong the QT interval, which increases the risk of developing serious arrhythmias.
4. Severe liver failure. Ondansetron is metabolized in the liver, and its use in patients with severe liver dysfunction may lead to accumulation of the drug and an increased risk of adverse effects.

Ondansetron should be used with caution in patients with:

• Chronic heart disease, especially if there are risk factors for prolongation of the QT interval.
• Electrolyte imbalances, as this may influence the risk of QT prolongation.

Side effects Domegana

1. Headache: This is one of the most common side effects associated with ondansetron.
2. Drowsiness: Some people may feel drowsy or tired while taking this medicine.
3. Constipation or Diarrhea: Some patients may experience gastrointestinal problems such as constipation or diarrhea.
4. Dizziness: This side effect may occur in some patients when using Domegan.
5. Muscle weakness: Rarely, some people may experience muscle weakness while using this medication.
6. Depression or mood changes: Some people may experience depression, anxiety, or other mood changes.
7. Allergic reactions: In rare cases, an allergic reaction may occur, which may include skin rash, itching, swelling of the face, or difficulty breathing.
8. Extrapyramidal symptoms: These symptoms include shaking, stomach cramps, or unusual body movements that may occur with ondansetron, especially in children.

Overdose

An overdose of Domene (ondansetron) can cause a variety of symptoms and complications, including increased side effects such as dizziness, headache, drowsiness, increased heart rate (tachycardia), changes in the electrocardiogram (ECG), possibly even cardiac arrhythmias.

Interactions with other drugs

1. Drugs that prolong the QT interval: Ondansetron may increase the prolongation of the QT interval on the ECG. Concomitant use with other drugs such as antiarrhythmic drugs (eg, amidaron, sotalol) or antiarrhythmic antibiotics (eg, erythromycin, clarithromycin) may increase the risk of cardiac arrhythmias.
2. Serotonergic drugs: Concomitant use of ondansetron with other serotonergic drugs, such as selective serotonin reuptake inhibitors (SSRIs) or triptans, may increase the risk of developing serotonin syndrome.
3. Drugs that enhance anticholinergic effects: Concomitant use with drugs that have anticholinergic properties, such as antihistamines, some antispasmodics and antidepressants, may enhance the anticholinergic effects of ondansetron.
4. Drugs that increase the risk of hypertension: Ondansetron may increase the risk of hypertensive crisis when used concomitantly with monoamine oxidase inhibitors (MAOIs), certain antidepressants, or serotonin synthesizers.
5. Drugs that enhance the effects of sedation or decreased reflexes: Concomitant use of ondansetron with drugs such as benzodiazepines, hypnotics, or alcohol may enhance their sedative effect.