I used to be an oncology, so I was experienced in giving vessicant chemotherapy. Strangely enough, I've seen more problems from Dilantin than I have from vessicants! I always wonder if that's just been my personal experience, or how common Dilantin problems are. I have seen the purple glove syndrome - a woman whose hand was edematous and purple/black from a Dilantin extravasation. I saw it early in my career, and it made a big impression on me. So, now I really assess the IV site, and blood return very cautiously prior to giving it, I usually push it slowly through a free-flowing NS IV - clamp, push, let the saline flow, repeat, check for blood return halfway through and at the end, assess the site throughout, just like giving chemo.) I advocate for po Dilantin when appropriate. I also keep in mind what I learned as a chemo RN; i.e. the worst place to give a vessicant is somewhere that it's difficult to do a plastic surgery repair - that is, the hand would be worse than the forearm. So I'm more cautious, and more aggressive about changing iffy sites if they are in the hand or wrist. On the bright side, I've only see the purple hand thing once in over 10 years, and mostly I've just seen complaints of burning. I'm just a worrywart, but it doesn't hurt to be cautious.