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.
Botox is best known for smoothing out wrinkles, but since 2010 it’s also been used to prevent migraines. (Scientists aren’t 100 percent sure why Botox works, though it may interfere with the transmission of pain signals to the brain.) Though the 36 injections I get every three months in my forehead, skull, neck, and shoulders are painful, they’ve been a game changer. I went from 16 to 18 migraines a month to about eight. The intensity of the pain has gone down, too. The results are so good that I find myself frustrated that I spent so many years in unnecessary misery.

But today it's the medical uses of the drug that are the great moneymaker, in part because doctors are getting a better handle on how to use it. Botulinum toxin type A is one of seven neurotoxins produced from Clostridium botulinum. Contracting botulism is bad news: it can cause blurred vision, persistent trouble swallowing and worse. In one recent case, close to 30 people were hospitalized in Ohio in 2015 after attending a church potluck. One person died. The outbreak was ultimately attributed to a potato salad made from improperly home-canned potatoes that were harboring the bacteria. Given its level of toxicity, some countries have even explored its potential use as a bioweapon.
The needle should be inserted approximately 2 mm into the detrusor, and 30 injections of 1 mL (~6.7 Units) each (total volume of 30 mL) should be spaced approximately 1 cm apart (see Figure 1). For the final injection, approximately 1 mL of sterile normal s aline should be injected so that the remaining BOTOX in the needle is delivered to the bladder. After the injections are given, the saline used for bladder wall visualization should be drained. The patient should be observed for at least 30 minutes post -injection.
The safety and effectiveness of BOTOX® for hyperhidrosis in other body areas have not been established. Weakness of hand muscles and blepharoptosis may occur in patients who receive BOTOX® for palmar hyperhidrosis and facial hyperhidrosis, respectively. Patients should be evaluated for potential causes of secondary hyperhidrosis (eg, hyperthyroidism) to avoid symptomatic treatment of hyperhidrosis without the diagnosis and/or treatment of the underlying disease.

On July 29, 2016, Food and Drug Administration (FDA), of the United States of America approved abobotulinumtoxinA for injection for the treatment of lower limb spasticity in pediatric patients two years of age and older.[20] AbobotulinumtoxinA is the first and only FDA-approved botulinum toxin for the treatment of pediatric lower limb spasticity. In the United States of America, the FDA approves the text of the labels of prescription medicines. The FDA approves which medical conditions the drug manufacturer may sell the drug for. However, those approved by the FDA to prescribe these drugs may freely prescribe them for any condition they wish, called off-label use. Botulinum toxins have been used off-label for several pediatric conditions, including infantile esotropia.[21]

It is not known whether BOTOX® is safe or effective to treat increased stiffness in upper limb muscles other than those in the elbow, wrist, fingers, and thumb, or in lower limb muscles other than those in the ankle and toes. BOTOX® has not been shown to help people perform task-specific functions with upper limbs or increase movement in joints that are permanently fixed in position by stiff muscles. BOTOX® is not meant to replace existing physical therapy or other rehabilitation that may have been prescribed.