Azacitidine is used in the treatment of myelodysplastic syndromes and other conditions, but patients with severe liver injury, pregnant women, and breastfeeding patients are contraindicated populations and must be strictly managed.

I. Patients with Severe Liver Injury

1. Contraindicated Use

Azacitidine is contraindicated in patients with severe liver injury. The drug is mainly metabolized by the liver; when liver function is severely impaired, drug clearance decreases, exposure increases, and the risk of hepatotoxicity and systemic toxicity rises.

2. Liver Function Monitoring

In patients with abnormal liver function, transaminases, bilirubin, and other indicators must be closely monitored before and during treatment; if marked elevation or jaundice occurs, the drug should be stopped immediately and evaluated.

3. Dose Adjustment Principles

For patients with mild to moderate liver injury, the physician must assess benefits and risks and adjust the dose if necessary; for severe liver injury, dose reduction should not be attempted, and alternative regimens should be selected.

II. Pregnant Women

1. Contraindicated During Pregnancy

Azacitidine is contraindicated in pregnant women. Animal studies show that it has teratogenic and embryotoxic effects and can cause fetal harm.

2. Pregnancy Testing Before Use

Women of childbearing potential should confirm that they are not pregnant before use, and effective contraception must be used during treatment and for a period after discontinuation.

3. Management of Exposure During Pregnancy

If pregnancy occurs unexpectedly during treatment, inform the physician immediately to assess fetal risk and decide whether to continue the pregnancy.

III. Breastfeeding Patients

1. Contraindicated During Breastfeeding

Azacitidine is contraindicated in breastfeeding women. Whether the drug is secreted in breast milk is unclear, but considering its cytotoxicity, it may cause serious adverse reactions in infants.

2. Stop Breastfeeding or Stop the Drug

If use is unavoidable, breastfeeding must be stopped; if breastfeeding is continued, azacitidine should be discontinued and another regimen used.

3. Contraception and Follow-up During Breastfeeding

Breastfeeding is not a guarantee against pregnancy; contraception is still required during treatment; before resuming breastfeeding after discontinuation, consult the physician to assess drug clearance time.

IV. General Precautions

1. Individualized Assessment

Before treatment in the above populations, the physician must conduct a thorough assessment, inform them of the risks, and obtain informed consent.

2. Patient Education

Women of childbearing potential and breastfeeding patients should understand the importance of contraception and stopping breastfeeding, and must not use the drug on their own.

3. Timely Reporting

If jaundice, abnormal bleeding, fever, or signs of pregnancy occur, seek medical attention immediately.