CAN I EAT A LEAF OFF OF AN ALOE VERA PLANT ; OR IS IT POISON ?

No! Do not eat.

Ingestion Dangers
The ingestion of aloe juice or latex may irritate the intestines when taken orally. According to the University of Maryland Medical Center, aloe vera latex contains powerful laxative properties. Use of the aloin latex as a laxative may result in severe cramping and purging of the intestines. Misuse of aloin may lead to excessive electrolyte loss and has subsequently been banned by the Food and **** Administration for use in over-the-counter laxative medications as of 2002.

Hi Debbie:
I just googled it and it certainly appears to be.
Here is a link for you to check
https://www.google.ca/webhp?sourceid=chrome-instant&rlz=1C1GGGE_enCA468&ion=1&espv=2&ie=UTF-8#q=is%20aloe%20vera%20poisonous%20to%20humans
Before I considered eating it, I would check with my family doctor.
Hope this helps.