Y. Zhou, MD, PhD, FRCPC (Dermatology)
The Hyperhidrosis Clinic, Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
Excessive production of sweat, or hyperhidrosis, affects millions of people worldwide. Until recently, treatment was difficult. However, new advances have revolutionized the management options for many patients suffering from this condition.
Excessive Sweating vs. Hyperhidrosis
Sweating is a necessary physiological mechanism, and under certain conditions, such as physical exertion or illness, it can become excessive. However, it is not necessarily hyperhidrosis, which is defined as nonphysiological, excessive sweating that is not caused by physical activity and occurs symmetrically in a localized fashion. In either case, it can have a significant negative impact on a patient’s quality of life, including difficulty with work, school, and social relationships. As a result, patients often shy away from situations that require shaking hands or other forms of close physical contact with other people.
Primary Focal Hyperhidrosis (PFHH)
- The most common form of hyperhidrosis
- Affects about 5% of the general population.
- Most frequently affects the axillae, hands, and feet; the face and the groins can also be involved.
Several forms of treatment are now available for the management of PFHH. The options are slightly different and depend on the condition (excessive sweating vs. hyperhidrosis) and locations involved.
Axillary Excessive Sweating/ Hyperhidrosis
- Available over-the-counter.
- The most commonly used first-line treatment for those who have regular sweating (deemed to be excessive by the patient) and hyperhidrosis who are seeking a less costly, noninvasive option.
- Preferred by patients due to relatively low cost.
- Aluminum chloride solutions
- The effective ingredient frequently used in concentrations ranging from 10%–25%.
- Rarely offers complete wetness control, but can be very helpful for many people.
- Local irritation at the application site can limits tolerability.
- Aluminium zirconium trichlorohydrex complex
- A new form of topical antiperspirant
- Will be available soon in North America.
- Similar efficacy, but may have less irritating side effects than aluminum chloride-based products.
Subcutaneous Injection of Botulinum Toxin
- When injected by experienced physicians, it can be highly effective for the cessation of sweat production in areas of administration.
- It works by blocking acetylcholine release, a neurotransmitter secreted by the sympathetic nerves innervating the sweat glands.
- There is no spread of the toxin to other body systems, which could cause unwanted effects.
- There are no significant side-effects.
- More than 90% reduction in sweat production for more than 90% of patients.
- Repeated injections are necessary, usually one to two treatments each year.
- Relatively high in cost. However, most private health insurance carriers cover the cost of the drug for this indication with submission of appropriate paperwork.
- An injection of botulinum toxin eliminates the frequent use of topical antiperspirants and potentially saves costs associated with replacement of clothing.
Surgical Management of Axillary Hyperhidrosis
Surgical removal of the sweat glands in the axillae, or ablating the sympathetic chain supplying the sweat glands can also be performed for selected patients. However, unwanted effects of surgical treatment can include:
- • With sweat gland removal
- Relapsed sweating
- With sympathectomy
- Risk of intrathoracic injury to the lungs and other nerve structures
- Compensatory hyperhidrosis.
Consequently, these procedures are reserved for those who do not respond to other treatment options.
Oral anticholinergics such as glycopyrolate can offer mildto- moderate relief for some patients suffering from PFHH. However, because of the systemic side-effects such as dry mouth, blurred vision, and reduced gastrointestinal motility, systemic anticholinergics have not been the accepted therapy for most patients.
Hyperhidrosis affecting the hands and the feet is also very common, alone or in combination with axillary hyperhidrosis. The treatment options are similar to axillary hyperhidrosis.
As for excessive sweating and axillary hyperhidrosis, antiperspirants containing aluminium salts in concentrations ranging from 10%–25% are considered the first-line therapies.
Botulinum Toxin Subdermal Injections
It is highly effective for most patients. Cost of botulinum toxin therapy is significantly higher than for axillary hyperhidrosis because palmoplantar hyperhidrosis requires significantly larger doses.
Tap Water Iontophoresis
- Iontophoresis works by delivering micro-amounts of electric current through the medium of tap water.
- The mechanism of action is unknown, however, it may involve plugging the eccrine sweat gland pores.
- Initially, frequent treatment sessions are required to be effective.
- Once significant control of sweating is attained, infrequent maintenance therapy is all that is necessary for moderate-to-significant long-term control.
- It is relatively low in cost when compared with botulinum toxin, although the effect is also less pronounced.
- There are no significant side-effects.
- May be tried by patients before sympathectomy.
As for axillary hyperhidrosis oral anticholinergics, such as glycopyrolate, can offer mild-to-moderate relief for some patients suffering from PFHH. However, because of systemic side-effects, systemic anticholinergics have not been considered as the accepted therapy for most patients.
Endoscopic Trans-Thoracic Sympathectomy
- Surgical ablation of the sympathetic nerve chain supplying the sweat glands to the hands can also be performed for selected patients.
- It can be very effective and long lasting for some patients.
- There are concerns of complications such as injury to other critical structures in the chest, and the troubling side-effect of compensatory hyperhidrosis. Therefore, this procedure is reserved for patients who cannot get adequate relief from other treatment options.
For most patients, antiperspirants containing aluminium salts are the first-line treatments. Other therapeutic options, especially for those with hyperhidrosis, include botulinum toxin injection, systemic anticholinergics, iontophoresis and surgery. Individualized patient counselling and careful attention to adverse effects are the keys to treatment satisfaction.