Multiple systemic side effects may occur during treatment with Cobimetinib, and different response measures should be taken according to the severity.

1 Common Self Relieving Side Effects

(1) Skin reaction: About 50% of patients experience rash and photosensitivity. It is recommended to use SPF50+sunscreen and wear protective clothing.

(2) Gastrointestinal symptoms: Mild diarrhea (<4 times a day) can be treated with oral loperamide, and 5-HT3 receptor antagonists can be used for nausea and vomiting.

(3) Fatigue and fatigue: It is recommended to engage in activities in different time periods, maintain 8 hours of sleep per day, and avoid sudden changes in body position.

Serious side effects requiring medical intervention

(1) Cardiotoxicity: When chest pain, palpitations, or lower limb edema occur, stop taking the medication immediately and test for electrocardiogram and troponin.

(2) Visual impairment: Sudden visual impairment or visual distortion indicates retinal vein occlusion, requiring emergency ophthalmology within 24 hours.

(3) Liver injury: permanent discontinuation of medication when jaundice, clay stool, and ALT levels increase by more than three times, and liver protection treatment if necessary.

3 targeted mitigation plans

(1) Skin care: Apply 1% hydrocortisone ointment to the rash area, soak in iodine for paronychia, and avoid trimming nails too short.

(2) Dietary adjustment: During diarrhea, adopt BRAT diet (banana, rice, apple sauce, toast) and supplement electrolyte solution.

(3) Drug adjustment: Dosage adjustment is required for grade 2 and above side effects, and for grade 3-4 side effects, consideration should be given to suspending or terminating treatment.

4 Special precautions

(1) Bleeding risk: When combined with anticoagulant drugs, nosebleeds and hematuria may occur, and coagulation function needs to be monitored.

(2) Embryotoxicity: Pregnant women should avoid using it, and patients of childbearing age should take effective contraceptive measures during treatment.

(3) Drug interactions: CYP3A4 inhibitors can increase blood drug concentrations, so avoid using potent inhibitors in combination.