Botox: Medical and cosmetic use

  GP Mohanta, PK Manna and K. Saravanan Wednesday, September 05, 2012, 08:00 Hrs[IST] Botox is a trade name with active ingredient Botulinum toxin A administered as injection for either therapeutic or cosmetic use. Botulinum toxin is an exotoxin produced by the bacterium Clostridium botulinum and is known as the most toxic substance known. It has been estimated that one mg is enough to kill about 20 million mice. The LD50 of this toxin is estimated to be 40-56 ng [intravenous] in monkeys. Expressing the potency of toxicity, it has been reported that four kilograms of this toxin is enough to kill the entire human race. Though research exploiting this toxin for therapeutic purpose has been initiated in late 1960s, it got first the United States Food and Drug Administration (US FDA) approval in 1989 as treatment for two rare eye muscle disorders and in 2002 as a wrinkle reducer. In 2011, the US FDA further approves Botox for treatment of urinary incontinence in patients with neurological conditions like spinal cord injury and multiple sclerosis. With this new indication, there are seven medical conditions: cervical dystonia (neuromuscular disorder involving head and neck), excessive sweating, chronic migraine, uncontrollable blinking of eyes, increased muscle stiffness with upper limb spasticity, visual defects with eyes not properly aligning with each other, and urinary continence; where Botox find usefulness. In India Botox is approved for use in the year 2006.

Botox for cosmetic use In addition to the above seven medical indications, Botox is approved for cosmetic use to improve the look of moderate to severe frown lines between the eye brows. This helps in augmenting the facial appearance of a person by reducing the wrinkles present on the face thus making a person look younger.The face is frozen in time and feel good factor about self becomes the driving force for this cosmetic use. The treatment result lasts about four months and requires continuing further treatment."The 48 year old bollywood queen looks gorgeous – the cheeks look fuller than the usual". "The legendary actor had cosmetic injection to look like a college boy in one of the most impressive movies of recent times." These are some of the headlines of news supplements of reputed daily newspapers. Yes, these are the success of Botox. It has helped people all over the world to look young than what they are! But not without the risks!The product is injected into the concerned muscle. It works by blocking the transmission of nerve impulses to muscles, causing those muscles to relax. It decreases the muscle activity by blocking the release of acetylcholine from the neuron by preventing the vesicles where the acetylcholine is stored from binding to the membrane where the neurotransmitter can be released. This effectively weakens the muscles. Relaxation of the muscles between the eyes causes wrinkles to disappear. Injection of Botox to the bladder results in relaxation of the bladder increasing storage capacity and decreases urinary incontinence. These cosmetic and therapeutic effects are due to local effects of the Botox.Unfortunately the Botox is not just restricted to the site of injection. Its propensity to spread to the parts of the body distance from injection site is a cause of concern as it affects the other system. In particular, if the gastrointestinal tract is affected, the ability to swallow could be impaired; the patient might regurgitate, inhale some stomach contents, and develop aspiration pneumonia. Loss of control of oesophagus leads to uncontrolled, abnormal swallowing, called 'dysphagia'. This can be serious enough where the patients can no longer eat or drink and need hospitalization. Independent of swallowing problems, the drug can additionally impair breathing. The common toxic effects observed due to spread of the toxin to other parts include: loss of strength and muscle weakness throughout the body, double vision, blurred vision and dropping eyelids, hoarseness or change or loss of voice, trouble saying clearly, loss of bladder control, trouble breathing, trouble swallowing. These are the symptoms of botulinum toxin commonly known as botulism. The problems of swallowing, breathing, or speaking may appear even after several weeks of injection.This occurs due to weakness of the muscles required for speaking, swallowing and breathing. These conditions are often life threatening leading to deaths.

Adverse events There has been report of 554 suspected cases of adverse events occurred during November 1997 to December 2006 in USA due to Botox. This included 25 deaths that appeared directly linked to medicine in use. Public Citizen Group of USA urged the US FDA to issue strongest warning on the Botox's label warning the physicians on its propensity to spread to other parts of the body distant from the site of injection. The mild reactions occur at the site of injection are pain and bruising, redness, light swelling etc. can be easily managed with application of ice before and after injection. However, the allergic reactions like rash or itchy welts, wheezing or difficulty breathing or swallowing, dizziness or faintness, experiencing muscle weakness, difficulty speaking, double or blurred vision, or lose of bladder control may require immediate medical attention and even hospitalization. The patients or the clients (cosmetics users) need to be informed to understand the serious adverse events so that they can avail the medical help without delay.Like all other medicines, the Botox too has risk. Therapeutic use involves higher doses of drugs than cosmetic use. The drug has been widely used and the adverse events have been observed with approved and unapproved indications. The careful consideration of benefit – risk ratio and clear understanding of this both by the physician and the patients (and clients) would promote safe and effective use of this prescription medicine for therapeutic and cosmetic purposes.