Cobimetinib, as a MEK inhibitor, should be used with special attention to cardiac toxicity, skin reactions, and medication risks in special populations. The following provides a detailed explanation of medication standards from three aspects: basic monitoring, system toxicity management, and special precautions.

1. Basic monitoring requirements

(1) Pre treatment assessment: Confirm baseline electrocardiogram QT interval, liver function, and retinal condition.

(2) Periodic monitoring: Electrolytes are tested every 2 weeks, and LVEF echocardiography is rechecked monthly.

(3) Symptom Diary: Record daily body temperature, bowel movements, and skin changes.

2. System toxicity management

2.1 Cardiovascular system

(1) QT prolongation: Avoid using fluoroquinolone antibiotics in combination and maintain blood potassium levels above 4.0 mmol/L.

(2) Heart failure: Discontinue medication immediately when there is shortness of breath or paroxysmal difficulty breathing at night after activity.

2.2 Skin reactions

(1) Photosensitivity: When going out, wear UPF50+protective clothing to avoid exposure to ultraviolet rays from 10:00-16:00.

(2) Rash: local use of clindamycin gel can be used for papular pustular rash, and oral administration of doxycycline can be used for infection.

2.3 Eye toxicity

(1) Retinal vein occlusion: Sudden visual impairment requires completion of fundus fluorescein angiography within 24 hours.

(2) Serous detachment: Discontinue medication after OCT examination confirmation, usually reversible within 2-4 weeks.

3 Special precautions

(1) Pregnancy risk: Women of childbearing age need to complete a pregnancy test within 7 days before treatment and use dual contraception during medication.

(2) Drug interactions: The combination of potent CYP3A4 inducers (such as carbamazepine) is prohibited as it can cause a 70% decrease in blood drug concentration.

(3) Postoperative management: Stop medication for 3 weeks before major surgery, and resume medication at 50% of the original dose after wound healing.