What are the key counseling points and teaching instructions for patients prescribed osimertinib (Tagrisso)?

Osimertinib Patient Teaching and Counseling

Patients starting osimertinib must be counseled immediately about life-threatening adverse events—particularly interstitial lung disease/pneumonitis, heart failure, and severe skin reactions—and instructed to report specific warning symptoms without delay. 1

Critical Safety Warnings to Emphasize

Lung Problems (Highest Priority)

• Instruct patients to contact their provider immediately if they develop:
  • New or worsening shortness of breath
  • Persistent cough
  • Fever with respiratory symptoms
  • Trouble breathing
• Explain that osimertinib can cause severe, potentially fatal lung inflammation (ILD/pneumonitis) that may mimic lung cancer progression 1

Heart Problems

• Report immediately any signs of heart failure:
  • Feeling like the heart is pounding or racing
  • Shortness of breath (especially when lying down)
  • Swelling of ankles and feet
  • Dizziness, lightheadedness, or feeling faint
• Inform patients that heart function will be monitored during treatment 1

Eye Problems (Keratitis)

• Contact provider immediately for:
  • Watery eyes
  • Light sensitivity
  • Eye pain or redness
  • Vision changes
• May require referral to ophthalmologist 1

Severe Skin Reactions

• Seek immediate care if developing:
  • Target-shaped lesions (rings on skin)
  • Severe blistering or peeling skin
  • Purple spots or non-blanching redness on forearms, lower legs, or buttocks
  • Large hives on trunk lasting >24 hours with bruised appearance
• These may indicate Stevens-Johnson syndrome, toxic epidermal necrolysis, or cutaneous vasculitis 1

Blood and Bone Marrow Problems (Aplastic Anemia)

• Report immediately:
  • New or persistent fever (≥100.4°F)
  • Easy bruising or bleeding that won't stop
  • Unusual paleness
  • Persistent infections
  • Extreme tiredness or weakness
• Blood counts will be monitored regularly 1

Common Expected Side Effects

Counsel patients that the following are common but manageable 2, 3:

• Skin changes: Rash, dry skin, nail problems (paronychia)—most frequent in first 4-6 weeks, typically improve over time 4, 5
• Diarrhea: Usually mild-to-moderate; provide antidiarrheal management plan
• Fatigue: Common throughout treatment
• Mouth sores (stomatitis)
• Musculoskeletal pain
• Cough and itching: Often improve after initial weeks 4

Key point: Most common side effects are rated low-to-moderate in severity by patients and are generally well-tolerated 4, 5

Medication Administration

• Dose: 80 mg once daily (standard dose) 1
• Timing: Can be taken with or without food 1
• Duration:
  • Adjuvant setting: Up to 3 years or until recurrence 1
  • Metastatic/advanced disease: Until disease progression or unacceptable toxicity 1
• Missed dose: Take as soon as remembered unless next dose is due within 12 hours

Drug Interactions

• Avoid strong CYP3A4 inducers (e.g., rifampin, phenytoin, St. John's wort)—these reduce osimertinib effectiveness 1
• Inform all providers about heart and blood pressure medications due to QTc prolongation risk 1

Reproductive Counseling

For Women

• Use effective contraception during treatment and for 6 weeks after final dose 1
• Do not breastfeed during treatment and for 2 weeks after final dose 1
• Notify provider immediately if pregnancy occurs or is suspected 1

For Men

• Use effective contraception during treatment and for 4 months after final dose 1

Monitoring and Follow-up

• Regular blood count monitoring will be performed 1
• Heart function assessments as clinically indicated 1
• Imaging studies to assess treatment response per standard protocols 6
• Emphasize importance of keeping all appointments—pharmacist-led consultation and intervention significantly extends treatment duration (median 561 vs 203 days without consultation) 7

Treatment Expectations

Set realistic expectations 4:

• Most patients report high satisfaction with osimertinib treatment
• Side effects are generally manageable with low difficulty coping
• Symptom profile may change over time—respiratory symptoms and diarrhea may increase after 4 months, while rash and itching typically decrease
• Treatment continuation is possible even with moderate radiological progression if clinical benefit continues 6

When to Contact Provider

Create a clear action plan:

• Emergency/same-day contact: Any symptoms listed under critical safety warnings above
• Routine contact: Manageable side effects, questions about medication administration
• Never stop medication without discussing with oncology team first

Special Considerations

• Osimertinib has superior CNS penetration compared to earlier-generation EGFR TKIs, making it particularly effective for brain metastases 6, 3
• If disease recurs after completing adjuvant osimertinib, rechallenge may be considered 8
• If progression occurs while on osimertinib, rebiopsy may be needed to guide next treatment 8, 6