The management of vomiting after taking Neratinib requires different measures based on the time of vomiting, with the core principle being to avoid the risk of overdose caused by repeated administration. The following provides specific explanations from three aspects: supplementary medication rules, precautions, and medical indications.

1. Remedial treatment after vomiting

(1) Vomiting immediately after taking medication: If vomiting occurs within 15 minutes after taking medication, it is recommended to take the full dose as the medication may not be fully absorbed.

(2) Vomiting 15-60 minutes after taking medication: Half of the dose can be taken as a supplement or based on the nature of the vomit (if a complete pill is visible, it needs to be taken as a supplement).

(3) Vomiting after more than 1 hour: usually no need for supplementation, just take the next dose according to the original plan.

2 Precautions

(1) Prohibition of double dosage: Under no circumstances should double the dosage in the next dose to prevent drug accumulation and poisoning.

(2) Dietary management: It is recommended to eat small amounts (such as biscuits) when taking medication to avoid exacerbating gastrointestinal irritation on an empty stomach.

(3) Position adjustment: Keep your upper body upright for 30 minutes after taking medication to reduce the risk of reflux.

3 situations requiring medical attention

(1) Frequent vomiting: Vomiting ≥ 3 times within 24 hours or inability to eat or drink water, be alert to dehydration and electrolyte imbalance.

(2) Accompanying symptoms: severe symptoms such as vomiting blood, severe abdominal pain, and blurred consciousness should be sought medical attention immediately.

(3) Weight loss: Continuous vomiting leading to a weight loss of more than 5% requires adjustment of the treatment plan.

4 Preventive measures

(1) Antiemetic medication: Consult a doctor for prophylactic use of 5-HT3 receptor antagonists such as ondansetron.

(2) Split administration: Discuss with the doctor whether daily split administration can be used to reduce single stimulation.

(3) Medication time: Choose a time when the gastrointestinal tract is relatively stable (such as after lunch) to take.