Ondansetron Side Effects

Medically reviewed by Drugs.com. Last updated on Jan 15, 2024.

Applies to ondansetron: film, solution, tablet, tablet disintegrating.

Other dosage forms:

• injection solution

Serious side effects of ondansetron

Along with its needed effects, ondansetron may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking ondansetron:

More common side effects

• confusion
• dizziness
• fast heartbeat
• fever
• headache
• trouble breathing

Less common side effects

• decrease in the frequency of urination
• decrease in the urine volume
• difficulty with passing urine (dribbling)
• painful urination

Rare side effects

• arm, back, or jaw pain
• chest pain, discomfort, tightness, or heaviness
• cough
• decreased urine
• difficulty with breathing
• difficulty with swallowing
• dry mouth
• fast, pounding, or irregular heartbeat or pulse
• increased thirst
• loss of appetite
• loss of bladder control
• loss of consciousness
• mood changes
• muscle pain or cramps
• nausea or vomiting
• noisy breathing
• numbness or tingling in the hands, feet, or lips
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• seizures
• skin rash, hives, or itching
• sweating
• total body jerking
• unusual tiredness or weakness

Incidence not known

• agitation
• blistering, peeling, or loosening of the skin
• blurred vision
• chills
• diarrhea
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• fixed position of the eye
• heart stops
• hoarseness
• inability to move the eyes
• increased blinking or spasms of the eyelid
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• no pulse or blood pressure
• noisy breathing
• overactive reflexes
• pain or discomfort in the arms, jaw, back, or neck
• poor coordination
• pounding heartbeat
• red irritated eyes
• red skin lesions often with a purple center
• restlessness
• shivering
• slow or irregular breathing
• sore throat
• sores, ulcers, or white spots in the mouth or on the lips
• sticking out of the tongue
• sweating
• talking or acting with excitement you cannot control
• trembling or shaking
• trouble with speaking
• twitching
• unconscious
• uncontrolled twisting movements of the neck, trunk, arms, or legs
• unusual facial expressions
• vomiting

Other side effects of ondansetron

Some side effects of ondansetron may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

• anxiety
• difficulty having a bowel movement (stool)
• dry mouth
• general feeling of discomfort or illness
• hyperventilation
• irritability
• shaking
• trouble sleeping

Rare side effects

• difficulty with speaking
• drooling
• loss of balance control
• muscle trembling, jerking, or stiffness
• shuffling walk
• stiffness of the limbs
• uncontrolled movements, especially of the face, neck, and back

Incidence not known

• feeling of warmth
• hiccups
• redness of the face, neck, arms, and occasionally, upper chest
• redness of the skin

For healthcare professionals

Applies to ondansetron: injectable solution, intravenous solution, oral disintegrating strip, oral solution, oral tablet, oral tablet disintegrating.

General adverse events

The most frequently reported side effects are headache, constipation, and diarrhea.^[Ref]

Nervous system

• Very common (10% or more): Headache (up to 27%), drowsiness/sedation (up to 23%)
• Common (1% to 10%): Dizziness, paresthesia
• Uncommon (0.1% to 1%): Seizures, movement disorders/extrapyramidal reactions (oculogyric crisis/dystonic reactions, dyskinesia)
• Rare (0.01% to 0.1%): Grand mal seizures^[Ref]

Dizziness occurred during rapid IV administration.

Headache occurred more often in the oral dissolving tablet formulation when taken with water.^[Ref]

Other

• Very common (10% or more): Wound problem (up to 28%), malaise/fatigue (up to 13%)
• Common (1% to 10%): Shivers, pyrexia/fever, cold sensation
• Frequency not reported: Pain, ear disorder^[Ref]

Wound problems occurred at the surgical site in patients given this drug for the treatment of postoperative nausea and vomiting.^[Ref]

Gastrointestinal

• Very common (10% or more): Diarrhea (up to 16%), constipation (up to 11%)
• Common (1% to 10%): Xerostomia, nausea, vomiting, localized anal/rectal burning sensation
• Uncommon (0.1% to 1%): Throat disorder
• Frequency not reported: Gastric symptoms, abdominal pain, flatulence^[Ref]

Localized anal/rectal burning occurred after insertion of the suppository formulation.^[Ref]

Ocular

• Very common (10% or more): Eye disorder (up to 19%)
• Common (1% to 10%): Visual disturbance/transient visual disturbances (e.g., blurred vision)
• Uncommon (0.1% to 1%): Oculogyric crisis
• Very rare (less than 0.01%): Transient blindness
• Frequency not reported: Swollen periocular area^[Ref]

Oculogyric crisis occurred alone and in combination with other dystonic reactions.

Transient visual disturbances, blurred vision, and transient blindness occurred predominantly during rapid IV administration. Many of the cases of blindness resolved from within a few minutes to approximately 28 hours. Most patients were receiving concomitant chemotherapy with cisplatin.^[Ref]

Cardiovascular

• Common (1% to 10%): Sensation of warmth/flushing, bradycardia, hypotension, arrhythmias
• Uncommon (0.1% to 1%): Chest pain with/without ST segment depression
• Rare (0.01% to 0.1%): Transient ECG changes including QT interval prolongation (Torsade de Pointes), angina/chest pain, vascular occlusive events, tachycardia
• Frequency not reported: Hemorrhage
• Postmarketing reports: Cardiopulmonary arrest, shock^[Ref]

Cardiopulmonary arrest and shock occurred during allergic reactions in patients given the IV formulation.^[Ref]

Respiratory

• Common (1% to 10%): Hypoxia, lower respiratory tract disease, expectoration, cough
• Uncommon (0.1% to 1%): Hiccups
• Rare (0.01% to 0.1%): Bronchospasm/asthma
• Postmarketing reports: Shortness of breath, laryngeal edema, stridor, laryngospasm^[Ref]

Laryngospasm occurred during allergic reactions in patients given the IV formulation.^[Ref]

Psychiatric

• Common (1% to 10%): Anxiety/agitation, disturbance in behavior/conduct, sleep disturbance^[Ref]

Genitourinary

• Common (1% to 10%): Gynecological disorder, urinary retention, urinary tract infection/dysuria^[Ref]

Dermatologic

• Common (1% to 10%): Rash, pruritus
• Very rare (less than 0.01%): Toxic skin eruption, toxic epidermal necrolysis^[Ref]

Hepatic

• Common (1% to 10%): Asymptomatic increases in AST/ALT
• Postmarketing reports: Liver failure and death^[Ref]

Transient, asymptomatic increases in AST/ALT 2 times the upper limit of normal commonly occurred in patients receiving chemotherapy with cisplatin, and did not appear to be related to dose/duration of treatment.

Liver failure and death have been reported in patients with cancer receiving potentially hepatotoxic/cytotoxic chemotherapy and antibiotics; however, the etiology of liver failure is unknown.^[Ref]

Local

• Common (1% to 10%): Injection site reactions^[Ref]

Hypersensitivity

• Rare (0.01% to 0.1%): Immediate hypersensitivity reactions (sometimes severe), anaphylaxis/anaphylactoid reactions
• Postmarketing reports: Angioedema^[Ref]

Metabolic

• Rare (0.01% to 0.1%): Hypokalemia
• Frequency not reported: Poor oral intake^[Ref]

Frequently asked questions

• Can you take ondansetron while pregnant?

Further information

Ondansetron side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer