Axillary Hyperhidrosis (excessive underarm sweating)
What is Axillary Hyperhidrosis?
Axillary hyperhidrosis is the ‘medical’ name for excessive underarm sweating. It is a very distressing and embarrassing problem that affects 3-5% of people. There is almost certainly a genetic component to this condition as at least a quarter of patients have a close relative who also suffers with excessive sweating. Although it almost always seems to start around the time of puberty, no one has yet found a direct link between higher levels of hormones and hyperhidrosis. Due to the stigma associated with ‘being sweaty’, it can create anxiety and depression, can complicate business and social interactions, and ultimately can ruin lives. It can create restrictions on what clothes and colours you can wear (as the sweat can stain), and sufferers are often forced to carry extra clothing with them. Severe cases can have serious practical consequences as well, causing difficulty in holding a pen, gripping a steering wheel, wearing open-toe shoes or shaking hands. In a survey conducted in America in 2004, almost 70% of those who regularly or routinely suffered from excessive sweating had never talked to a health professional about it.
How and why do we sweat?
Sweating is essential for our bodies to maintain a normal temperature; if we did not sweat, then we would soon overheat (especially after exercise or on hot days). Sweating is mostly controlled by the sympathetic nervous system (which is also responsible for the other features of the ‘fight or flight’ response such as a faster heart rate and dilated pupils), through a relatively simple circuit. The brain detects that your body is getting too warm, and sends a signal down a nerve in the spinal cord. This nerve fibre leaves the spinal cord and enters a bundle of nerves called the sympathetic chain (there is one of these chains on either side of the spinal column – one for each side of your body). The signal is then transmitted to a second nerve fibre which runs from the sympathetic chain to the skin and into the sweat gland itself.
Hence there are a range of different treatments, as it is possible to intervene at different points in the circuit (see under ‘Treatments’)
Are there different types of hyperhidrosis?
Yes. The simplest way to classify excessive sweating is ‘primary’ (where sweating alone is the problem) or ‘secondary’ (where the sweating is caused by another problem). In primary hyperhidrosis, the sweat gland produces too much sweat because it is overstimulated. There is usually no identifiable cause, but it may be worsened by anything that further stimulates the sympathetic nervous system (such as anxiety, nicotine or caffeine). A common scenario that patients recount is that they get nervous because they know they sweat, and then sweat more because they are nervous. It may be localised to one particular area (such as the armpit, hands or feet), or it may be more generalised. Secondary hyperhidrosis occurs in relation to an underlying condition, some of which can be relatively common (such as diabetes and thyroid disease), or sometimes as a side effect of some medications.
How do hyperhidrosis patients present?
Patients with axillary hyperhidrosis usually complain of constant or frequent sweating, and in more severe cases with streams of wetness running down their sides. In addition to wetting (and even ruining) clothing, and the subsequent embarrassment, sufferers may have physical problems including skin breakdown and infections.
Most patients with axillary hyperhidrosis have tried multiple antiperspirants, medications and often have devised ingenious coping methods and clothing strategies. A few may have consulted their GPs or nurses, but unfortunately unsuccessfully.
The diagnosis is made on the basis of the patient’s account of their symptoms, and confirmed by visible signs of sweating. Some practitioners use a technique called ‘Iodine Mapping’ to attempt to quantify both the amount of sweat produced and the exact area that the sweating is coming from. However, in virtually all cases the area demonstrated by the iodine map corresponds almost exactly to the area where hair grows in the armpit, and for this reason I don’t routinely perform it as it doesn’t offer much extra information. In a similar way, there is no recognised scale of severity of symptoms (although some use the descriptive terms ‘mild’, ‘moderate’ and ‘severe’).
Looking at the diagram above which details the pathway leading to sweat production, there are several places where treatments can intervene in the ‘sweating circuit’. These are by blocking the sweat gland opening (physically preventing the sweat from leaving the gland), blocking the connection between the nerve fibre and the sweat gland, or by decreasing the activity of the sympathetic nervous system (both of which result in less stimulation of the gland).
Some current treatments and methods that currently exist to treat Hyperhidrosis are;
How does BOTOX® fit in with these other options?
Over the past few years, Botox injections have become an established treatment for axillary hyperhidrosis, and FDA approval was granted for this in 2004. It offers a very elegant solution to a difficult problem. It has similar success rates to surgery (and actually better in some cases), but without many of the risks. It works by blocking the release of neurotransmitter at the junction of the nerve fibre and the sweat gland, effectively ‘disconnecting’ the sweat gland from its nerve supply. The effect begins within a few days of treatment and lasts for a considerable time – patients usually experience four to nine months of effective symptom control initially, but this often increases to six to twelve months with repeated treatments. A few lucky individuals can get as much as eighteen months improvement from one treatment. Studies have shown that most people treated with Botox enjoy at least an 80% improvement in their condition. For anyone whose symptoms are not well controlled on the simple treatments, and even for those who are contemplating surgery due to the severity of their sweating, Botox may well provide the answer.
What does the treatment involve?
Firstly, a free consultation to decide whether the treatment is suitable for you. There are a few medical conditions and prescribed medications that we need to be aware of when considering Botox therapy.
Once we have determined that that it is suitable for you, then we will book a time for your treatment.
Whilst not absolutely essential, I highly recommend that your armpits are shaved a few days prior to treatment (especially if you are prone to folliculitis or any other irritation from shaving – the extra few days will allow the skin time to recover). If you prefer not to shave then a hair-removing cream is absolutely fine too. Wash under the arms immediately before you come to see me, but do NOT use a deodorant or anti-perspirant.
What is the starch/iodine test?
Some practitioners use this test to demonstrate the area of the axilla where sweating is most problematic. It involves ‘painting’ the armpit in an iodine solution, then applying a starch powder once the iodine has dried. After a short period of time, the starch will turn blue in the areas where sweating has occurred. However, I don’t believe that this test is actually very helpful. Firstly, the testing solution will stain any clothes that you put on afterwards. But more importantly, what the test shows in virtually EVERY case is that the area where sweating is most prevalent is the same as the area in which hair grows. Thus I think there is little benefit in performing the test as the area to be treated is very easily identified anyway.
What does the treatment actually involve?
I’ll ask you to lie back on a couch, put one hand behind your head, and I will clean your axilla with an antiseptic cleaner. Then I will mark out the injection sites. A good rule of thumb is that each individual injection will treat an area approximately the size of a thumbnail, and so depending on the size of the area to be treated, somewhere between 10 and 20 tiny injections will be required. The injections themselves can be a little uncomfortable, but as the skin in the armpit is quite thin, most people find them perfectly bearable. I’ll then apply some Arnica gel to help minimise any brusing, and then repeat the procedure on the other side. In total, around 100u of Botox are required to treat both armpits.
What should I do afterwards?
I would ask you to avoid waxing or using epilators on the treated areas for at least a couple of days afterwards.