Although fluoride advocates have claimed for years that the safety of fluoride in dentistry is exhaustively documented and “beyond debate,” the Chairman of the National Research Council’s (NRC) comprehensive fluoride review, Dr. John Doull, recently stated that: “when we looked at the studies that have been done, we found that many of these questions are unsettled and we have much less information than we should, considering how long this [fluoridation] has been going on. I think that’s why fluoridation is still being challenged so many years after it began.”
The following adverse reactions have been identified during post-approval use of BOTOX. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. These reactions include: abdominal pain; alopecia , including madarosis; anorexia ; brachial plexopathy; denervation /muscle atrophy ; diarrhea; hyperhidrosis; hypoacusis; hypoaesthesia; malaise ; paresthesia ; peripheral neuropathy ; radiculopathy ; erythema multiforme , dermatitis psoriasiform, and psoriasiform eruption; strabismus; tinnitus ; and visual disturbances.
Sometimes, putative medical adverse effects are regarded as controversial and generate heated discussions in society and lawsuits against drug manufacturers. One example is the recent controversy as to whether autism was linked to the MMR vaccine (or by thiomersal , a mercury -based preservative used in some vaccines ). No link has been found in several large studies, and despite removal of thimerosal from vaccines a decade ago the rate of autism has not decreased as would be expected if it had been the causative agent.