It has poisonous latex, however, the inner part of the flowers, minus the petals, is eaten raw by the Fulani and other nomadic tribes.
Charcoal from the roots is used by some of the locals(at least in the East of certain Sahelian countries) to counteract scorpion stings.
This is how the anti scorpion sting remedy was done, if I am remembering accurately:
1. Some Calotropis procera roots were dug up and burned into charcoal.
2. Some normal vegetable oil was poured into the dip of a Calotropis procera leaf and heated in the leaf over a flame. (The oil needs to be warm to hot, but not boiling)
3. The charcoal was crushed up and put on the sting site.
4. The hot oil was rubbed around the sting with a motion away from the body( lightly rubbing the oil from the knee to the foot for example)
5. The treatment was continued and repeated several times.
Other uses of Calotropis procera include:
The inner bark used to be used extensively as fiber material for rope, cord, net making, etc.
The longer sturdier branches are used in the Easter part of Sahelian countries as roofing poles of small rooms in houses (to hold up the straw and mud roof above) because of their termite resistance.
The branches are also used for other things which require termite resistance.
The small straight branches were, and still are by some nomads, used for the hand drill(a method of friction fire making).
Information from other sites:
Herb society http://www.herbsociety.org/promplant/cprocera.php