Purinethol

Let’s talk about Purinethol. If you’re in hematology-oncology or pediatric gastroenterology, you know this drug. It’s not new, it’s not flashy, but it’s absolutely foundational. The generic name is mercaptopurine, or 6-MP, and it sits in that category of drugs where the margin between therapeutic effect and significant toxicity is… well, let’s call it narrow. I’ve seen it save lives and I’ve seen it land people in the ICU with pancytopenia.