What are the side effects of Oseltamivir (Tamiflu)?

From the Guidelines

Tamiflu (oseltamivir) can cause several side effects, with the most common being nausea and vomiting, which affect about 10% of patients, as reported in the most recent study 1.

Common Side Effects

• Nausea
• Vomiting
• Headache
• Abdominal pain
• Diarrhea

Serious Side Effects

• Neuropsychiatric events such as confusion, abnormal behavior, hallucinations, and delirium, particularly in children and adolescents, although recent analyses have found that oseltamivir is not associated with an increased risk for neuropsychiatric events 1.

Administration and Dosage

• Oseltamivir is administered orally without regard to meals, although administration with meals may improve gastrointestinal tolerability 1.
• The standard dosage for adults is 75 mg twice daily for 5 days for treatment of influenza, or once daily for 10 days for prevention 1.
• Patients should complete the full course of medication even if symptoms improve.

Special Considerations

• Oseltamivir is approved by the FDA for children as young as 2 weeks of age, and can be used to treat influenza in both term and preterm infants from birth because benefits of therapy are likely to outweigh possible risks of treatment 1.
• Oseltamivir dosing for preterm infants is lower than for term infants, and should be based on postmenstrual age (gestational age + chronological age) 1.

From the FDA Drug Label

Oseltamivir phosphate for oral suspension may cause serious side effects, including: Serious skin and allergic reactions. Oseltamivir phosphate for oral suspension can cause serious skin and allergic reactions Stop taking oseltamivir phosphate for oral suspension and get medical help right away if you get any of the following symptoms: ○ skin rash or hives ○ your skin blisters and peels ○ blisters or sores in your mouth ○ itching ○ swelling of your face, eyes, lips, tongue, or throat ○ trouble breathing ○ chest pain or tightness Change in behavior. People, especially children, who have the flu, can develop nervous system problems and abnormal behavior that can lead to death. During treatment with oseltamivir phosphate for oral suspension, tell your healthcare provider right away if you or your child have confusion, speech problems, shaky movements, seizures, or start hearing voices or seeing things that are not really there (hallucinations) The most common side effects of oseltamivir phosphate for oral suspension when used for treatment of the flu include nausea, vomiting, and headache. The most common side effect of oseltamivir phosphate for oral suspension when used for prevention of the flu include nausea, vomiting, headache, and pain

The side effects of Oseltamivir (Tamiflu) include:

• Serious skin and allergic reactions
• Change in behavior, such as confusion, speech problems, shaky movements, seizures, or hallucinations
• Common side effects:
  • For treatment of the flu: nausea, vomiting, and headache
  • For prevention of the flu: nausea, vomiting, headache, and pain 2

From the Research

Side Effects of Oseltamivir (Tamiflu)

The side effects of Oseltamivir (Tamiflu) can be categorized into several groups, including:

• Neuropsychiatric symptoms:
  • Delirium 3
  • Behavioural disorders 3, 4, 5
  • Hallucinations 3
  • Convulsions 3
  • Confusion 3
  • Abnormal behavior 5
• Cutaneous adverse effects:
  • Lyell syndrome 3
  • Skin problems 6
• Other side effects:
  • Body pain 6
  • Gastrointestinal disturbances, including nausea, vomiting, diarrhea, and abdominal pain 5
  • Tongue swelling 7

Specific Populations

Certain populations may be more susceptible to the side effects of Oseltamivir, including:

• Children:
  • Increased risk of neuropsychiatric disorders 3
  • Severe cutaneous adverse effects, including Lyell syndrome 3
• Adolescents:
  • Increased risk of neuropsychiatric symptoms, including abnormal behavior 3, 5
• Adults with preexisting neuropsychiatric conditions:
  • Exacerbation of symptoms, including bipolar disorder, depression, and attention-deficit/hyperactivity disorder 4