While many people think of botulinum toxin type A (known by the brand names Botox and Dysport) as a treatment for wrinkles, it has actually been used for many years to treat certain medical conditions. In fact, its use as a cosmetic treatment was only realised when people using it to treat facial muscle spasms noticed an improvement in their facial wrinkles.
What is Botox?
Botox is one brand of a purified form of botulinum toxin type A, a chemical toxin that is produced by Clostridium botulinum bacteria. Although this is the same toxin that causes botulism — a type of infection that can result in life-threatening muscle paralysis — Botox is safe to use as an injectable medicine because it is used in such small quantities and injected directly into specific sites. Another brand of botulinum toxin type A, called Dysport, is also available.
How does Botox treatment work?
Botulinum toxin type A (Botox, Dysport) blocks the release of a neurotransmitter (a chemical messenger) known as acetylcholine from nerve cells. Acetylcholine normally transmits nerve impulses to muscle cells, causing them to contract. Without acetylcholine, the affected nerve is unable to send a signal to the muscle it supplies, resulting in a weakened or paralysed muscle. The effect of Botox injections is restricted to the area being treated, and because the nerve fibres usually regenerate after a couple of months, the effect is only temporary.
What are Botox injections used for?
Botox injections are used to treat medical conditions such as:
- blepharospasm (twitching or spasm of the eyelid);
- cervical dystonia, or spasmodic torticollis (a type of muscle spasm in the neck);
- facial or other localised muscle spasms;
- muscle spasticity due to cerebral palsy;
- strabismus (a condition where the eyes are not properly aligned); and
- certain cases of incontinence due to overactive bladder.
Botox injections can be directed into the skin to block the action of the nerves that control your sweat glands. It can be used in this way to treat excessive localised sweating (hyperhidrosis), especially severe underarm sweating.
Botox can also be used to help prevent migraine headaches in certain people with chronic migraine.
Botox injections are now approved for the cosmetic treatment of vertical frown lines (also called glabellar lines — lines between the eyebrows that are caused by the muscles that contract when you frown, squint or concentrate), horizontal forehead lines, and lines radiating from the corners of the eyes (crow's feet).
Another brand of botulinum toxin type A, known as Dysport, has been approved for the treatment of moderate to severe vertical frown lines between the eyebrows.
How are Botox injections used to treat wrinkles?
Botox injections can be used to weaken or paralyse some of the facial muscles that pull on your skin and cause wrinkles, allowing the skin to flatten out. About 2 to 7 days after the injections, the lines and wrinkles that are normally caused by certain facial expressions start to disappear. Because Botox therapy targets specific, individual muscles, the ability to form most facial expressions should not be affected.
How long does the effect last?
The improvement in the appearance of your wrinkles usually lasts for 3 to 6 months, and repeated injections are required to maintain the effect. With continued use, the effects may start to last longer.
A small number of people develop neutralising antibodies to Botox injections after repeated therapy, which results in the treatment no longer being effective.
Are Botox injections safe?
Botox injections are relatively safe when administered by a medical professional who is trained in its use. As with all treatments, there are some side effects associated with its use, but most of these are mild and temporary. Pain, tenderness and bruising may be associated with the injection, and some people have reported a slight headache after treatment. Nausea and a flu-like syndrome are also rarely reported.
There is only a small risk of significant side effects from Botox treatment, such as a drooping eyelid (which usually only lasts a few days, but can last longer).
Botox injections should not be used in women who are pregnant or breast feeding.
It's important to remember that that all medical procedures carry risks as well as benefits, and you need to discuss these with your doctor.