Chemotherapy Bleeding: Causes, Risks, and What You Can Do

When you're undergoing chemotherapy, a medical treatment that uses drugs to kill cancer cells. Also known as cancer chemotherapy, it's powerful—but it doesn't just target cancer. It can also damage healthy cells, including those that help your blood clot. One of the more serious but less talked-about risks is chemotherapy bleeding, uncontrolled or unusual bleeding caused by low platelet counts or damaged blood vessels. This isn't just a minor bruise. It can mean nosebleeds that won't stop, bleeding gums, blood in urine or stool, or even internal bleeding. If you're on chemo and notice anything out of the ordinary, don't wait—call your doctor.

Not all chemotherapy drugs carry the same risk. Drugs like melphalan, a chemotherapy agent used for multiple myeloma and ovarian cancer, are known to lower platelet counts more than others. Platelets are the cells in your blood that plug leaks in damaged vessels. When chemo knocks them down too far, even small bumps can cause bleeding. Other factors like liver damage, infections, or interactions with other meds can make it worse. If you're taking something like hydrochlorothiazide, a diuretic often used with blood pressure drugs, it might affect your electrolytes and make bleeding risks more complex. It's not the drug itself causing the bleed—it's how your body responds after weeks of treatment.

What can you do? First, know the signs: unusual bruising, tiny red dots on your skin (petechiae), or bleeding that doesn't stop after 10 minutes. Avoid aspirin, ibuprofen, or other NSAIDs—they thin the blood. Use a soft toothbrush, electric razor, and be careful with sharp objects. Your care team will check your blood counts regularly. If your platelets drop too low, they might pause chemo or give you a platelet transfusion. Some patients also benefit from growth factors that help your bone marrow make more platelets.

There’s no one-size-fits-all fix, but understanding your risk helps you take control. You’re not alone in this—many people on chemo deal with bleeding concerns, and your medical team has tools to help. The posts below cover real cases, drug comparisons, and practical tips from people who’ve been there. Whether you're worried about melphalan, managing side effects from other chemo drugs, or just trying to stay safe during treatment, you’ll find clear, no-fluff advice here.