Which drug is associated with hyperpigmentation as a major side effect?

Melphalan is known to be associated with hyperpigmentation as a major side effect. This occurs because melphalan is an alkylating agent that can lead to changes in skin pigmentation due to its effects on the melanin-producing cells. The drug can damage skin cells and alter normal pigmentation processes, resulting in a darker appearance of certain areas of the skin.

Other drugs in this context primarily exhibit different types of side effects. For example, oxaliplatin can cause peripheral neuropathy, paclitaxel is often linked to hair loss, and nelarabine might cause neurotoxicity. While other agents can cause skin changes, hyperpigmentation is particularly notable with melphalan, making it the most relevant choice in this instance.