That's the bottom line from a report in The Journal of the American Medical Association.
The researchers included the CDC's Daniel Chertow, MD, MPH.
They investigated four Florida botulism cases that occurred in late November 2004 in people who got facial shots of an unlicensed, highly concentrated botulinum toxin product.
Botulism is a rare, potentially fatal disease caused by the botulinum bacteria. Botulism can cause paralysis.
Cases Not Linked to Botox
It's important to note that Botox wasn't involved in the Florida botulism cases.
Botox is a licensed drug containing tiny amounts of botulinum toxin A; its uses include relaxing certain facial muscles to smooth out wrinkles.
Chertow's team notes no CDC reports of any lab-confirmed botulism cases linked to Botox.
The Florida cases involved an unlicensed, highly concentrated botulinum toxin product labeled for research purposes only.
The product "was never intended or approved for use in humans," write Chertow and colleagues.
They investigated the cases, which WebMD first reported on in December 2004.
The researchers say staff at a Florida clinic got the unlicensed product and diluted it.
The dilution process went wrong, leaving the solution with very high levels of botulinum toxin, but the clinic staff apparently didn't know that.
A clinic doctor gave himself and three patients four to six facial injections of the diluted solution for cosmetic purposes.
Within a few days, all four were hospitalized with botulism.
Their symptoms: progressive weakness and cranial neuropathies (abnormality of certain nerves in the face and neck that control functions including sensation, facial muscle movement, and swallowing).
Two of them also had shortness of breath.
All survived after lengthy hospital stays.
"Physicians and patients must be aware of the hazards associated with illegitimate use of unlicensed botulinum toxin products," write Chertow and colleagues.
"Only licensed products should be used clinically," the researchers add.
SOURCES: Chertow, D. The Journal of the American Medical Association, Nov. 22/29, 2006; vol 296: pp 2476-2479. WebMD Medical News: "Bogus Botox Fells 4 in Florida." FDA: "Botox." News release, JAMA/Archives.
By Miranda Hitti
Reviewed by Louise Chang