Can the leaves/sap cause numbness on my fingers?
Certified GKH Gardening Expert
While the plant does, in fact, get its name from the sap containing oxalate crystals that can cause intense numbness and irritation if ingested, I don't think this should be an issue by simply touching it. That said, overly sensitive individuals could exhibit irritation so it's probably best to wear gloves when handling the plant. If you've already come into contact with its sap, wash your hands thoroughly and call a doctor if it worsens.