The pulp in most cacti is acidic and not a safe source of water. The water of a barrel cactus can cause diarrhea, joint pain and, in some cases, paralysis.
About this Author
Michael Logan is a writer, editor and web page designer. His professional background includes electrical, computer and test engineering, real estate investment, network engineering and management, programming and remodeling company owner. Logan has been writing professionally since he was first published in "Test & Measurement World" in 1989.