Anzemet

Dolasetron comes as a tablet to take by mouth. It is usually taken within 1 hour before chemotherapy. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take dolasetron exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

For children unable to swallow the tablet, a specially prepared dolasetron liquid dose may be mixed in apple or apple-grape juice to take by mouth. This mixture may be kept at room temperature, but must be used within 2 hours after mixing.

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

Symptoms of overdose may include the following:

• dizziness
• fainting
• rapid, pounding, or irregular heart beat

Keep all appointments with you doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;
• a light-headed feeling, like you might pass out;
• slow heart rate, weak pulse, slow breathing;
• swelling in your hands or feet;
• little or no urinating; or
• high levels of serotonin in the body--agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting.

Common side effects may include:

• mild headache;
• mild dizziness;
• drowsiness; or
• pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers at once if you have:

• headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;
• a light-headed feeling, like you might pass out;
• slow heart rate, weak pulse, slow breathing;
• little or no urinating; or
• high levels of serotonin in the body--agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting.

Common side effects may include:

• headache, dizziness;
• fast or slow heart rate;
• chills, shivering, anxiety;
• upset stomach, diarrhea;
• tired feeling; or
• pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Dosage Forms & Strengths

injectable solution

• 20mg/mL

tablet

• 50mg
• 100mg

Cancer Chemotherapy Induced Nausea & Vomiting

Oral: 100 mg PO 1 hr before chemotherapy

Note: IV administration no longer indicated for CINV because of risk for QT prolongation

Post-op Nausea & Vomiting

Indicated for prevention and treatment of postoperative nausea and vomiting (PONV)

IV: 12.5 mg IV 15 minutes before cessation of anesthesia or as soon as N/V presents

Note: Oral tablet no longer indicated for PONV

Dosing considerations

Post-op nausea & vomiting

• As with other antiemetics, routine prophylaxis is not recommended for patients in whom there is little expectation that nausea and/or vomiting will occur postoperatively
• In patients where nausea and/or vomiting must be avoided postoperatively, a 5-HT3 receptor antagonist is recommended even where the incidence of postoperative nausea and/or vomiting is low
• When prophylaxis has failed, a repeat dose should not be initiated as rescue therapy

Dosage Forms & Strengths

injectable solution

• 20mg/mL

tablet

• 50mg
• 100mg

Cancer Chemotherapy Induced Nausea & Vomiting

<2 years: Safety and efficacy not established

2-16 years: 1.8 mg/kg PO 1 hr before chemotherapy; not to exceed 100 mg/dose 

IV may be administered PO in children aged 2-16 years: 1.8 mg/kg PO 1 hr before chemotherapy; not to exceed 100 mg/dose

Note: IV administration no longer indicated for CINV because of risk for QT prolongation

Postoperative Nausea & Vomiting

Indicated for prevention and treatment of post-op nausea and vomiting (PONV) in children ≥2 years

<2 years: Safety and efficacy not established

IV: 0.35 mg/kg 15 minutes before cessation of anesthesia or as soon as N/V develops; not to exceed 12.5 mg/dose 

IV may be administered PO in children aged 2-16 years: 1.2 mg/kg PO administered within 2 hr before surgery; not to exceed 100 mg/dose

Note: Oral tablet no longer indicated for PONV

Dosing considerations

Post-op nausea & vomiting

• As with other antiemetics, routine prophylaxis is not recommended for patients in whom there is little expectation that nausea and/or vomiting will occur postoperatively
• In patients where nausea and/or vomiting must be avoided postoperatively, a 5-HT3 receptor antagonist is recommended even where the incidence of postoperative nausea and/or vomiting is low
• When prophylaxis has failed, a repeat dose should not be initiated as rescue therapy

Administration

IV administered PO

• Injectable solution may be given PO mixed in apple-grape or apple juice
• Diluted product may be kept up to 2 hr at room temperature

Cancer chemotherapy induced nausea & vomiting

Oral: 100 mg PO 1 hr before chemotherapy

Note: IV administration no longer indicated for CINV because of risk for QT prolongation

Post-op nausea & vomiting

IV: 12.5 mg IV 15 minutes before cessation of anesthesia or as soon as N/V presents

Note: Oral tablet no longer indicated for PONV

Anzemet may cause serious side effects. See "Drug Precautions" section.

Common side effects of this medication include:

• headache
• diarrhea
• tiredness
• heartburn
• dizziness
• chills
• indigestion
• less frequent urination

Tell your doctor if any side effect is bothersome or doesn't go away. Especially tell your doctor right away if you experience any of these symptoms, which may be symptoms of serious side effects:

• dizziness
• fainting
• irregular heartbeat (fast or slow)
• chest pain
• hives, rash
• itching
• difficulty swallowing
• difficulty breathing

This is not a complete list of Anzemet  side effects. Ask your doctor or pharmacist for more information.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Hydrodolasetron is metabolized by CYP2D6 and CYP3A.1 2 3

Drugs that Prolong ECG Intervals

Potential pharmacologic interaction (e.g., additive effect on ECG interval prolongation).1 2 (See Cardiovascular Effects under Cautions.)

Avoid concomitant use with drugs that may prolong the PR or QRS interval or may result in electrolyte disorders that may prolong cardiac conduction (e.g., QT) intervals; if concomitant use is necessary, use caution and monitor ECG.1 2 18 Use with caution in patients receiving drugs that prolong the QT interval.1 2 (See Specific Drugs under Interactions.)

Drugs Affecting Hepatic Microsomal Enzymes

Potential pharmacokinetic interaction (altered dolasetron clearance) with inhibitors or inducers of CYP isoenzymes.1 2

Specific Drugs

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

QT Interval Prolongation

Anzemet prolongs the QT interval in a dose dependent fashion. Torsade de Pointes has been reported during post-marketing experience. Avoid Anzemet in patients with congenital long QT syndrome, hypomagnesemia, or hypokalemia. Hypokalemia and hypomagnesemia must be corrected prior to Anzemet administration. Monitor these electrolytes after administration as clinically indicated. Use ECG monitoring in patients with congestive heart failure, bradycardia, renal impairment, and elderly patients (see CLINICAL PHARMACOLOGY).

PR and QRS Interval Prolongation

Anzemet has been shown to cause dose dependent prolongation of the PR and QRS interval and reports of second or third degree atrioventricular block, cardiac arrest and serious ventricular arrhythmias including fatalities in both adult and pediatric patients. At particular risk are patients with underlying structural heart disease and preexisting conduction system abnormalities, elderly, patients with sick sinus syndrome, patients with atrial fibrillation with slow ventricular response, patients with myocardial ischemia or patients receiving drugs known to prolong the PR interval (such as verapamil) and QRS interval (e.g., flecainide or quinidine). Anzemet should be used with caution and with ECG monitoring in these patients. Anzemet should be avoided in patients with complete heart block or at risk for complete heart block, unless they have an implanted pacemaker (see CLINICAL PHARMACOLOGY). 

Serotonin Syndrome

The development of serotonin syndrome has been reported with 5-HT3 receptor antagonists. Most reports have been associated with concomitant use of serotonergic drugs (e.g., selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors, mirtazapine, fentanyl, lithium, tramadol, and intravenous methylene blue). Some of the reported cases were fatal. Serotonin syndrome occurring with overdose of another 5-HT3 receptor antagonist alone has also been reported. The majority of reports of serotonin syndrome related to 5-HT3 receptor antagonist use occurred in a post-anesthesia care unit or an infusion center.

Symptoms associated with serotonin syndrome may include the following combination of signs and symptoms: mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, with or without gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Patients should be monitored for the emergence of serotonin syndrome, especially with concomitant use of Anzemet and other serotonergic drugs. If symptoms of serotonin syndrome occur, discontinue Anzemet and initiate supportive treatment. Patients should be informed of the increased risk of serotonin syndrome, especially if Anzemet is used concomitantly with other serotonergic drugs (see DRUG INTERACTIONS, Patient Counseling Information).

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Anzemet can cause a serious heart problem, especially if you use certain medicines at the same time, including antibiotics, antidepressants, heart rhythm medicine, antipsychotic medicines, and medicines to treat cancer, malaria, HIV or AIDS. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with this medicine.

Taking Anzemet while you are using certain other medicines can cause high levels of serotonin to build up in your body, a condition called "serotonin syndrome," which can be fatal. Tell your doctor if you also use:

• medicine to treat depression;

• medicine to treat a psychiatric disorder;

• a narcotic (opioid) medication; or

• medicine to prevent nausea and vomiting.

This list is not complete and many other drugs can interact with dolasetron. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.