Erlotinib Medication Guidelines: Fasting, Omission Management, and Dose Adjustment
Erlotinib should be taken on an empty stomach to ensure stable absorption. Omission and dosage adjustment should follow the specifications. The following are specific points.
1、 Requirements for taking on an empty stomach
1. Medication time
Take at least one hour before meals.
Or take it at least 2 hours after meals.
It is necessary to take medication at the same time every day to maintain stable blood drug concentration.
2. The impact of food
Food can significantly increase the absorption of erlotinib and increase blood drug concentration.
A high-fat diet has a more significant impact and may increase the risk of adverse reactions.
Before and after taking medication, avoid eating and only drink water.
3. Drinking water recommendations
Serve with an appropriate amount of warm water.
Juice, milk, coffee and other beverages are not allowed for delivery.
Avoid taking grapefruit juice together as it may interfere with drug metabolism.
4. Interval with other medications
Avoid co administration with proton pump inhibitors and H2 receptor antagonists as they may reduce absorption.
If antacids are necessary, they should be taken several hours apart from erlotinib.
The specific interval time should be consulted with a doctor or pharmacist.
2、 Handling of missed services
1. After discovering a missed dose
If there is a long time before the next medication, it can be taken as soon as possible.
If it is close to the next medication time, the missed dose should be skipped.
Do not take double the dose at once to make up for it.
2. Post vomiting treatment
If vomiting occurs after taking medication, it is not recommended to take it again.
We should wait for the next medication according to the original plan.
No additional dosage is allowed.
3. Record and inform
Record the time of missed service and the handling method.
Repeated missed doses should be promptly reported to the doctor.
Doctors may adjust medication plans based on the situation.
3、 Principle of dose adjustment
1. Conventional dosage
Usually taken once a day on an empty stomach.
The specific dosage is determined by the doctor based on the condition and tolerance.
Do not increase or decrease the dosage on your own.
2. Adjustment during adverse reactions
When serious adverse reactions such as rash and diarrhea occur, doctors may suspend medication.
After the symptoms subside, it may be possible to restart at a lower dose.
The adjustment range and timing must follow the doctor's advice.
3. Adjustment during drug interactions
When used in combination with strong CYP3A4 inhibitors, it may be necessary to reduce the dosage.
When used in combination with strong CYP3A4 inducers, an increase may be required.
Before adjustment, the interaction risk should be evaluated.
4. When liver and kidney dysfunction occurs
Patients with liver function impairment may need to adjust the dosage.
Patients with renal dysfunction should be carefully evaluated when taking medication.
The specific plan will be determined by the doctor based on the examination results.
5. Attention smokers
Smoking can accelerate the metabolism of erlotinib and reduce blood drug concentration.
Smokers may require higher doses.
After quitting smoking, it is necessary to inform the doctor in a timely manner that the dosage may need to be readjusted.
Disclaimer：《Erlotinib Medication Guidelines: Fasting, Omission Management, and Dose Adjustment》Edited and sorted by Seagull Pharmacy's editors. Please contact us in time if there is any infringement. In addition, the suggestions for drug usage, dosage and disease mentioned in the article are only for medical staff's reference, and can not be used as any basis for medication！