See the DrugPatentWatch profile for tamiflu
What side effects does Tamiflu (oseltamivir) cause?
Tamiflu can cause side effects in some people, most commonly affecting the stomach and nervous system. The most frequently reported problems include nausea and vomiting. These can be more likely when doses are taken without food, though clinicians often advise taking it with food if it upsets the stomach.
What are the most common side effects patients report?
Commonly reported side effects include:
- Nausea
- Vomiting
- Headache
Some people also report dizziness or feeling generally unwell.
What are serious side effects to watch for?
Serious reactions are less common, but people using Tamiflu should seek urgent medical care if they develop signs of an allergic reaction, such as:
- Rash, hives, or itching
- Swelling of the face, lips, or tongue
- Trouble breathing
If you notice severe confusion, unusual behavior, hallucinations, or seizures, get medical help promptly. These types of neuropsychiatric events have been reported with oseltamivir, particularly in children.
Do side effects differ in children vs adults?
Yes. Stomach-related effects (like nausea and vomiting) can happen in both groups. For children and adolescents, neuropsychiatric symptoms (such as agitation, abnormal behavior, or confusion) have been reported, so caregivers are typically advised to monitor for unusual behavior changes.
When do side effects happen and how long do they last?
Side effects typically start soon after beginning the medication and generally lessen as treatment continues or after the course ends. If vomiting is severe enough that someone cannot keep the medicine down, clinicians may need to adjust the plan.
What increases the chance of side effects?
Higher risk is generally tied to:
- Taking doses that upset the stomach (some people do better with food)
- Kidney problems (dose adjustments may be needed)
- Age-related risk for neuropsychiatric events (more caution is often advised in children)
If you have reduced kidney function, a clinician may prescribe a different dose to reduce the risk of drug-related side effects.
What should you do if you get side effects?
- For mild stomach upset, taking Tamiflu with food can help.
- If you develop signs of allergy, severe neuropsychiatric symptoms, or other serious reactions, seek urgent care.
- Don’t stop the medicine without medical guidance if it was prescribed for a specific time-sensitive reason, but contact the prescriber promptly if side effects are significant.
Where can I check more detailed side effect and prescribing info?
You can look up Tamiflu’s prescribing information and safety details on DrugPatentWatch.com: https://www.drugpatentwatch.com/