University-based ophthalmologists in the USA and Canada further refined the use of botulinum toxin as a therapeutic agent. By 1985, a scientific protocol of injection sites and dosage had been empirically determined for treatment of blepharospasm and strabismus. Side effects in treatment of this condition were deemed to be rare, mild and treatable. The beneficial effects of the injection lasted only 4–6 months. Thus, blepharospasm patients required re-injection two or three times a year.
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, 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.
Serious and/or immediate hypersensitivity reactions have been reported. These reactions include anaphylaxis, serum sickness, urticaria, soft tissue edema, and dyspnea. If such a reaction occurs, further injection of BOTOX should be discontinued and appropriate medical therapy immediately instituted. One fatal case of anaphylaxis has been reported in which lidocaine was us ed as the diluent, and consequently the causal agent cannot be reliably determined.
Most insurance providers now recognize BOTOX as treatment for migraines. Some have specific criteria that patients must meet, or require documentation that you have gone through other treatment protocols before trying BOTOX. It can take several weeks to receive authorization to begin treatment. Check with your insurance provider to make sure you fulfill their requirements, and to begin the approval process.
The FDA now requires black box labeling on Botox and similar products such as Dysport and Xeomin to warn of rare but potentially life-threatening swallowing and breathing complications if the toxin spreads beyond the injection site. None of these complications have occurred in people using Botox for cosmetic reasons and the FDA states that cosmetic use of Botox appears to be safe.
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. Types C–G are less common; types E and F can cause disease in humans, while the other types cause disease in other animals. Type H is considered the deadliest substance in the world – an injection of only 2 ng can cause death to an adult. 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.
Allergan Plc engages in the research, development, and manufacture of pharmaceutical products. The firm offers products under the following brands: BOTOX, Juvederm, Linzess, Namenda, Restasis, Latisse, Teflaro, Lo Loestrin Fe, Bystolic, DORYX, Saphris, Fetzima, Namenda XR, Namzaric, Viberzi, Viibryd, Alphagan, LUMIGAN, ESTRACE Cream, Rapaflo, Asacol, DELZICOL, Zenpep, Avycaz, and Dalvance. Its brand portfolio delivers treatments that address unmet medical needs in therapeutic categories such as dermatology and aesthetics;Read More
The FDA approval was based on a large study showing that Botox significantly reduced migraine frequency and severity, as well as headache-related disability, compared to placebo. As just one measure of its effectiveness, many of my patients report that they’ve cut their use of rescue medications in half since starting Botox – a significant benefit for people who previously had to resort to rescue medications 15 or more times every month.
There has not been a confirmed serious case of spread of toxin effect away from the injection site when BOTOX® has been used at the recommended dose to treat chronic migraine, severe underarm sweating, blepharospasm, strabismus, or when BOTOX® Cosmetic has been used at the recommended dose to treat frown lines, crow’s feet lines, and/or forehead lines.