What counseling should be provided to a patient diagnosed with influenza regarding the use of Tamiflu (oseltamivir)?

Tamiflu (Oseltamivir) Patient Counseling

Timing and Administration

Begin Tamiflu as soon as possible within 48 hours of symptom onset for maximum benefit, but treatment should not be withheld in high-risk or severely ill patients even if presenting beyond 48 hours. 1, 2

• Take the medication exactly as prescribed: 75 mg twice daily for 5 days for adults and adolescents ≥13 years 3, 4
• Take with food to reduce nausea and vomiting, which are the most common side effects 4, 5
• If you miss a dose, take it as soon as you remember unless it is within 2 hours of the next scheduled dose, then skip the missed dose and continue at the usual times 4
• Complete the full 5-day course even if you start feeling better 3, 2

Expected Benefits

Tamiflu reduces illness duration by approximately 1-1.5 days when started within 48 hours of symptom onset. 1, 2

• Reduces fever duration and severity of symptoms like fatigue, muscle aches, and cough 1, 6
• Decreases risk of complications including pneumonia by 50% and ear infections by 34% in children 1
• Helps you return to normal activities, health status, and sleep patterns faster 6
• Reduces the need for antibiotics and hospitalization 1, 2

Common Side Effects and Management

The most common side effects are nausea and vomiting, occurring in approximately 15% of patients, but these are typically mild, transient, and occur mainly with the first dose. 1, 4

• Taking Tamiflu with food significantly reduces nausea and vomiting 4, 5
• These gastrointestinal effects rarely lead to stopping the medication (only 1.8% discontinuation rate) 7
• Other possible side effects include headache and diarrhea 2

Important Safety Warnings

Stop Tamiflu immediately and seek medical attention if you develop signs of an allergic reaction including rash, hives, swelling of face/lips/tongue, or difficulty breathing. 4

• Contact your physician if you experience signs of abnormal behavior, confusion, or neuropsychiatric symptoms while taking Tamiflu 4
• If you have hereditary fructose intolerance, be aware that each 75 mg dose contains 2 grams of sorbitol, which may cause stomach upset and diarrhea 4

When to Seek Further Medical Care

Contact your healthcare provider immediately if symptoms worsen after 3+ days of treatment, as this may indicate bacterial superinfection requiring antibiotics. 8

• Warning signs include: persistent productive cough with colored mucus, new ear pain, worsening shortness of breath, or fever returning after initial improvement 8
• Seek emergency care for: respiratory rate >24/min, oxygen saturation <90%, inability to maintain oral intake, altered mental status, or persistent high fever despite 48 hours of treatment 8

Critical Misconceptions to Address

Tamiflu is NOT a substitute for annual flu vaccination—you should still receive your yearly flu shot. 4

• Tamiflu treats active influenza infection but does not provide long-term protection 4
• If you received the nasal spray flu vaccine (live attenuated), avoid taking it within 2 weeks before or 48 hours after Tamiflu, as the medication may reduce vaccine effectiveness 4
• Tamiflu does not treat or prevent bacterial infections that may occur with the flu 4
• Tamiflu only works against influenza virus—it will not help with common colds or other viral infections 4

Special Populations

High-risk patients (elderly, pregnant women, immunocompromised, chronic heart/lung disease) benefit from treatment even when started after 48 hours and should not delay starting Tamiflu. 1, 2

• Pediatric dosing is weight-based, ranging from 30 mg to 75 mg twice daily depending on the child's weight 3
• Patients with kidney problems may require dose adjustment to 75 mg once daily 3, 2