Botox (Onabotulinumtoxin A) is a brand of toxin used for the treatment of wrinkles predominantly on the upper third of the face but can also be used as a treatment on the lower face by an experienced injector.
Botox blocks the action of acetylcholine, a common neural transmitter that stimulates striated as well as smooth muscle and the secretion of glands such as sweat glands. Once the Botox has been injected it diffuses into the tissue where it interferes with proteins responsible for producing acetylcholine, essentially preventing the muscles from communicating and inducing a temporary paralysis.
It is important to understand that the action of Botox does not occur immediately. The first effects might be visable at around 3 days but it can take upto 2 weeks for the full effects to be seen. Depending on the strength of the muscles treated and dosages used, the duration of treatment lasts on average 3-4 months although this might be up to 6 months in some cases. The action of the drug slowly diminshes during this time.
There is large body of evidence to support the safety and efficacy of Botox. It has been used medically for over 20 years and millions of procedures are performed each year. Although the risks are low, side effects can occur. Most common are redness, swelling or bruising to the injection site, headache (temporary)and more rarely, eyelid or eyebrow ptosis can occur. This is when the product migrates to a distant muscle causing a droop to the eyelid or a heaviness to the brow. Generally this does not last as long as the treatment itself and, where the eyelid has drooped, drops can be prescribed to help improve the symptoms.