Types of Chemotherapy Drugs that Cause Hair Loss

• Classes of Chemotherapy Drugs
• Chemo Drugs Unlikely to Cause Hair Loss

Most chemotherapy agents used to treat cancer are highly toxic and induce hair loss in an estimated average of 65% of cancer patients, depending on the type of drug. In fact, alopecia is one of the top three major adverse effects due to toxicity of these drugs. Although doctors and nurses tend to underestimate the tremendous psychological impact chemotherapy-induced hair loss causes cancer patients, it is a serious side effect that can negatively affect a patient’s overall cancer treatment outcome with the potential risks of depression, anxiety, and even rejection of certain chemotherapy regimens.⁽⁴⁾

Chemotherapy is the primary cause of a certain type of hair loss called anagen effluvium, which affects both scalp and body hair. At lower doses it can produce a telogen effluvium. The effects of chemotherapy are meant to interrupt rapidly dividing cancer cells. Unfortunately, hair in the growth phase is comprised of rapidly dividing cells too. With up to 90% of hair in the anagen phase at any given time, the hair loss can be dramatic. Typically it begins within the first few weeks of treatment and reaches its maximum loss in about two months. Hair loss caused by chemotherapy drugs is usually reversible, though it may take up to six months to start regrowth.^{(29, 32, 89)}

Classes of Chemotherapy Drugs

Chemotherapy drugs are generally grouped into four major types, or classes. Each type carries a different risk of alopecia, but combination therapies using two or more drugs typically cause higher and more severe rates of loss.⁽³²⁾

Chemo Drugs Unlikely to Cause Hair Loss

The good news is that even within some of the classes with higher risk of hair loss, there are some chemotherapy drugs where hair loss is unusual. These include:⁽³²⁾