No, Annie, it's not a joke, see (I'm sorry for this reference in french)
http://www.doctissimo.fr/medicament-MESTINON.htm
"non soumis à prescription médicale" means it may be sold without prescription.
It is perhaps the reason why is only available in France in small bottles of 20-60mg pills.
Mestinon is sold here for myasthenia but also to increase bowel transit and
I've never heard of that second use in the States.
Now about the risk you mentioned, I think it is inherent with any drug, the leaflets in each drug box are there to protect the manufacturer but also to inform the patients about the recommended dosage and the possible side effects.
Maurice