Before taking chlorambucil, tell your doctor or pharmacist if you are allergic to it; or to other alkylating agents (such as busulfan, cyclophosphamide); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: gout, bleeding/blood problems, liver disease.

Chlorambucil can make you more likely to get infections or may make current infections worse. Stay away from anyone who has an infection that may easily spread (such as chickenpox, COVID-19, measles, flu). Talk to your doctor if you have been exposed to an infection or for more details.

Tell your health care professional that you are using chlorambucil before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).

To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

Before having surgery, tell your doctor or dentist about all the products you use (such as prescription drugs, nonprescription drugs, and herbal products).

Children may be more sensitive to the side effects of this drug, especially infertility later in life or seizures.

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using chlorambucil. Chlorambucil may harm an unborn baby. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this drug. Consult your doctor before breastfeeding.