Contrary to popular belief, the bacteria that causes botulism, clostridium botulinum, is not part of the treatment, nor are six of the seven neurotoxins it secretes. The only substance used in Botox injections, botulinum toxin A, is carefully extracted, purified, and standardized into FDA-approved doses. Plus, the dosage is so small, it can't get beyond the muscle tissue it's injected into, meaning there's little if any chance for Botox to reach the bloodstream.
Side effects from therapeutic use can be much more varied depending on the location of injection and the dose of toxin injected. In general, side effects from therapeutic use can be more serious than those that arise during cosmetic use. These can arise from paralysis of critical muscle groups and can include arrhythmia, heart attack, and in some cases seizures, respiratory arrest, and death.[27] Additionally, side effects which are common in cosmetic use are also common in therapeutic use, including trouble swallowing, muscle weakness, allergic reactions, and flu-like syndromes.[27]
There are eight types of botulinum toxin, named type A–H. Types A and B are capable of causing disease in humans, and are also used commercially and medically.[3] Types C–G are less common; types E and F can cause disease in humans, while the other types cause disease in other animals.[4] Type H is considered the deadliest substance in the world – an injection of only 2 ng can cause death to an adult.[5] Botulinum toxin types A and B are used in medicine to treat various muscle spasms and diseases characterized by overactive muscle. Commercial forms are marketed under the brand names Botox and Dysport, among others.[6][7]
Even if Botox's mechanism isn't always well understood and some of its off-label uses are still unproven, interest in the drug isn't likely to wane. "Botox is a big cash cow for the physicians' practices," says Ronny Gal, an investment analyst at Sanford C. Bernstein who has watched the drug closely for more than a decade. "When I talk to physicians, they say, 'Botox is not a problem. It works and gives you the result you want.' If it works for depression and atrial fibrillation, it could be massive."
Investors have been unhappy with Allergan's stock performance over the last year, and some have expressed interest in seeing the pharma company explore splitting up. On Wednesday, Allergan announced it plans to sell its women's health and infectious disease businesses. The news sent Allergan's stock down 2%, suggesting the move didn't go as far as some would like.
Strabismus is caused by imbalances in the actions of muscles that rotate the eyes, and can sometimes be relieved by weakening a muscle that pulls too strongly, or pulls against one that has been weakened by disease or trauma. Muscles weakened by toxin injection recover from paralysis after several months, so it might seem that injection would then need to be repeated. However, muscles adapt to the lengths at which they are chronically held,[18] so that if a paralyzed muscle is stretched by its antagonist, it grows longer, while the antagonist shortens, yielding a permanent effect. If there is good binocular vision, the brain mechanism of motor fusion, which aligns the eyes on a target visible to both, can stabilize the corrected alignment.

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BOTOX® treats the symptoms of severe underarm sweating when topical medicines do not work well enough in people 18 years and older. It is not known whether BOTOX® is safe or effective for severe sweating anywhere other than your armpits. BOTOX® treatments temporarily block the chemical signals from the nerves that stimulate the sweat glands, resulting in reduced sweating.
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