Dark Armpits

Dark armpits are also termed axillary hyperpigmentation. The most frequent causes are friction related or post inflammatory. The latter responds very well to pico lasers. Lasers can provide fast, effective & painless skin lightening. Other causes of dark underarms are harder to treat predictably with lasers & chemical peels.

Recovery

Immediate

Results

6-8 weeks, variable

Treatment Time

2-3 minutes

Aftercare

NA

Treatment science score

The science of Dark Armpit Treatments

  • Picosecond lasers are excellent in addressing post inflammatory darkening of the armpits.
  • Common causes of inflammation include friction & skin irritation.
  • Glycolic acid toners can help reduce pigment.
  • Genetic causes of dark underarms are more resistant to treatment.
  • Metabolic causes are best managed by endocrinologist dieticians.
  • Understanding the cause of pigmentation is the very first step.

Understanding the cause of dark armpits is the first step of management. Post inflammatory cases of dark underarms respond to lasers.

Why do dark underarms occur?

Darkening of the underarm/armpit area can be due to genetic causes, secondary to inflammation or commonly a combination of the above. Darkening occurs because of increased pigmentation production or increased skin thickness.

Treatments are aimed at reducing the pigment content in the upper & lower layers of the skin, in addition to increasing the exfoliation of pigment.

What are common conditions & solutions for dark armpits?

To treat, one must understand the causes of dark underarms, here is a quick summary-

  • Post inflammatory hyperpigmentation is the most common cause. It can be due to skin irritation, laser or waxing of the under arms.
  • Endocrine causes; acanthosis nigricans.
  • Frictional causes; sweating, weight gain.
  • Genetic causes.

Read more to understand how to find out the cause & treatment options.

How many laser sessions will I require & when will I see results?

Results can be seen within one to two treatment sessions. Freckle clearance can be expected within 5 days & continue to improve over the next week or two.

The Melasma Clinic difference

Our specialist clinic is overseen by dermatologists who provide a comprehensive & bespoke approach to skin care. We take into account the complexity and individuality of your skin. Our pigment solutions include preventing future recurrences of melasma. Our ethos is to improve & maintain your skin’s health & vitality as an ongoing commitment to our patients.

How to treat dark underarm patches / axillary hyperpigmentation?

Treatments can a combination of the following –

  1. Skin care at home: this is for mild cases of pigmentation in the absence of inflammation. Read more below.
  2. Prescriptive skin care by a medical dermatologist is best if there is inflammation.
  3. Laser treatment by procedural dermatologist for some cases of underarm pigment. Combination treatment provides the best results.

Dr Davin Lim

650K subscribers

What skin care ingredients can be used to treat dark armpit patches?

Several skincare ingredients can be used to treat dark underarm patches effectively:

Alpha Hydroxy Acids (AHAs): AHAs such as glycolic acid and lactic acid can help exfoliate dead skin cells, lighten dark patches, and promote skin cell turnover, resulting in a brighter and more even skin tone. We recommend using a wash off exfoliating toner that contains 7% glycolic acid, read more for instructions on how to.

Vitamin C: Vitamin C is a potent antioxidant that can help reduce the appearance of hyperpigmentation by inhibiting melanin production and promoting collagen synthesis, leading to brighter and more radiant skin. It is hard to use in the underarm area as skin irritation is commonly seen.

Retinol & retinoids: much like vitamin C, they can be irritating to the underarm skin. Far easier to use for facial pigmentation. Read below to understand how to use retinol in the delicate folds of the underarm.

Niacinamide:  Also known as vitamin B3, niacinamide can help lighten dark spots and hyperpigmentation by inhibiting melanin transfer to the skin’s surface and reducing inflammation. It also supports the skin's natural barrier function, resulting in improved overall skin health. It is much safer to use compared to vitamin C

Arbutin: Arbutin is a natural skin-lightening agent derived from bearberry, cranberry, or mulberry plants. It works by inhibiting tyrosinase, the enzyme responsible for melanin production, and can help fade dark underarm areas over time.

Kojic Acid: Kojic acid is another natural skin-lightening ingredient derived from various fungi. It works by inhibiting tyrosinase activity and melanin production, making it effective for reducing the appearance of dark spots and hyperpigmentation.

When using skincare ingredients to treat dark underarm patches, it’s essential to use them consistently but most importantly as tolerated. If your dark underarm patches are due to post inflammatory hyperpigmentation & your skin is still inflamed, chances are, active skin care ingredients may flare up this condition. A medical dermatologist can guide you.

*The Melasma Clinic employs a procedural dermatologist, one who performs laser procedures. For cases that require prescription medications & further investigations, you will be referred to a medical dermatologist at Cutis Dermatology in Brisbane or the Skin Hospital in Westmead or Darlinghurst in Sydney.

Can prescription creams fade dark underarm skin?

Creams have a marginal effect on dark underarms. Your medical dermatologist will guide you. Three types of creams can be used, depending on the cause. 

  1. Calcineurin inhibitors such a tacrolimus or pimecrolimus (Protopic or Elidel). This group of creams do not have the long-term side effects of steroids. They can be effective in preventing post inflammatory hyperpigmentation.
  2. Vitamin D creams can be effective in some cases of acanthosis nigricans (about 15% of cases).
  3. Pigment inhibitors are used when Ashy dermatosis is in the remission phases. They include hydroquinone, arbutin, azelaic acid, ascorbic acid & cysteamine. Creams are marginally effective & ideally should be combined with lasers & medical therapy.
  4. Corticosteroids to reduce inflammation. Example: Advantan Fatty ointment. This is used in a pulse manner (your dermatologist will guide you). Steroid creams are only useful in the very early phase of Ashy, even then, their use is controversial as it is used more commonly in other skin conditions that may look like Ashy- e.g. lichen planus pigmentosus.
  5. Botox is an injection, not a cream. It can be very effective in prevention of post-inflammatory hyperpigmentation, especially in cases of friction induced pigment due to excessive sweating or hyperhidrosis. 

Dermatologists at The Melasma Clinic are procedural, namely we perform procedures such as lasers & peels. Though we can provide second options, diagnose & investigate all forms of axillary hyperpigmentation, we do not provide ongoing medical management as this entails frequent visits, follow ups & prescriptive medications. We refer patients to Cutis Dermatology in Brisbane, or the Skin Hospital in Sydney for joint management with a medical dermatologist.

What results can I expect from lasers?

Lasers work best for cases of post inflammatory hyperpigmentation once the source of inflammation has subsided. Most patients can expect a reduction of pigmentation by up to 50-80% within a few sessions, spaced 4 weeks apart. 

The Melasma Clinic has the most advanced lasers for pigment, including the Picoway & Picosure Pro. Genetic cases may require 10 sessions with a success rate of only 20%, whilst conditions such as acanthosis nigricans do not respond well to lasers. 

What is the treatment like?

Treatments are comfortable & fast, taking less than 2 minutes to perform. On a pain scale of 1 to 10, it rates as a 1. Results are seen within the first 4 to 8 weeks. 

Peel type

Recovery

Number of sessions

Costs

Glycolic Nil 5 $
Cosmelan 7 days 1 $$$
Jessner TCA 8 days + 1 $$$$

What types of underarm-armpit pigment are hard to treat?

The two main conditions that are super hard to treat are acanthosis nigricans & genetic causes. 

Genetically, an increase in pigmentation can be seen in the underarm area, groin, around the eyes & the mouth. It is termed ‘constitutional.’ Lasers can be effective in some cases, however it requires up to 10 sessions over many months. 

Acanthosis nigricans is frequently seen with PCOS. It is very resistant to laser treatment & should be managed by endocrinologist, dietitians & medical dermatologist.

What natural remedies are there to lighten dark armpit skin?

Natural remedies & home therapies are unsuccessful in most cases, however if you would like to give natural therapy a try, here is the guide –

  • Glutathione 500 mg daily.
  • Add glycolic acid washes daily.
  • Apply niacinamide (vitamin B) or retinol  (vitamin A) in the evening. 

The highest success for DIY or home remedies is to use a 7% glycolic acid exfoliating wash, which is discussed below. 

This concept is grasped by only a handful of patients as most melasma patients can not see beyond pigmentation itself. Those who get it will have a much higher probability of long term remission 💯
.
👉Rate limiting factors: ability to understand the cause of melasma beyond pigment, the time required to remodel the dermis, especially in skin of colour, financial constraints as dermal remodelling goes far beyond ‘retinol-retinoids’, RFM, lasers & EBDs or the ubiquitous & over-rated Cosmelan peel
.
😎Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#melasma #melasmatips #photoaging #melasmaclinic #celluaraging #drdavinlim

This concept is grasped by only a handful of patients as most melasma patients can not see beyond pigmentation itself. Those who get it will have a much higher probability of long term remission 💯
.
👉Rate limiting factors: ability to understand the cause of melasma beyond pigment, the time required to remodel the dermis, especially in skin of colour, financial constraints as dermal remodelling goes far beyond ‘retinol-retinoids’, RFM, lasers & EBDs or the ubiquitous & over-rated Cosmelan peel
.
😎Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#melasma #melasmatips #photoaging #melasmaclinic #celluaraging #drdavinlim
...

204 4
The use of antioxidants such as glutathione can lighten & brighten skin. Glutathione can be a useful adjunct in some cases of #melasma
.
🔫Pico lasers: can safely be used to treat various types of pigmentation. A series of 3-5 sessions produce the best results, however in this patient only one treatment was performed. Settings matter
.
😎Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#sunscreen #picolaser #picosurepro #drdavinlim #davinlim #sydneydermatologist #themelasmaclinic #glutathione #skinlightening

The use of antioxidants such as glutathione can lighten & brighten skin. Glutathione can be a useful adjunct in some cases of #melasma
.
🔫Pico lasers: can safely be used to treat various types of pigmentation. A series of 3-5 sessions produce the best results, however in this patient only one treatment was performed. Settings matter
.
😎Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#sunscreen #picolaser #picosurepro #drdavinlim #davinlim #sydneydermatologist #themelasmaclinic #glutathione #skinlightening
...

69 4
If the proper amount of sunscreen is used, anything over an SPF of 40 is fine (in the context of melasma). Other than SPF factor (a measure of UVB), UVA ratings & attenuation of visible light is super important in the management of pigmentary disorders such as melasma & post-inflammatory hyperpigmentation, especially in skin of colour
.
👉Cosmetic elegance & colour matching: is often the rate limiting factor
.
👉Why tint? Iron oxides protect against visible light, this band of light stimulates pigment
.
👉How to use? Two fingerlengths, twice daily, regardless of exposure💯
.
👉Our pick? Elta MD, acknowledging there are many good brands with a wider range of colour matching
.
Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#sunscreen #melasmatips #bestsunscreen #spf #drdavinlim #davinlim #sydneydermatologist #themelasmaclinic #elta #eltaMD #eltasunscreens

If the proper amount of sunscreen is used, anything over an SPF of 40 is fine (in the context of melasma). Other than SPF factor (a measure of UVB), UVA ratings & attenuation of visible light is super important in the management of pigmentary disorders such as melasma & post-inflammatory hyperpigmentation, especially in skin of colour
.
👉Cosmetic elegance & colour matching: is often the rate limiting factor
.
👉Why tint? Iron oxides protect against visible light, this band of light stimulates pigment
.
👉How to use? Two fingerlengths, twice daily, regardless of exposure💯
.
👉Our pick? Elta MD, acknowledging there are many good brands with a wider range of colour matching
.
Dr Davin Lim
Dermatologist
The Melasma Clinic
Sydney, Australia🇦🇺
.
#sunscreen #melasmatips #bestsunscreen #spf #drdavinlim #davinlim #sydneydermatologist #themelasmaclinic #elta #eltaMD #eltasunscreens
...

45 2

The Melasma Clinic can diagnose all forms of pigmentation

Our specialist clinic is overseen by dermatologists who have extensive experience in the treatment of all forms of pigmentation, including dark underarm pigmentation. 

What is acanthosis nigricans & who should I see for treatment?

AN or acanthosis nigricans is a common skin condition that affects the armpit areas leading to dark patches. It can also affect the neck, groin & in some cases the face. This condition is managed by medical dermatologists, not procedural specialists in our clinic.

There are three treatment arms for acanthosis nigricans. 

  1. Diet & lifestyle changes. By far, this is the most effective method. Your GP, dietician & endocrinologist will guide you through weight loss & insulin management. Metformin 500 to 1500 mg daily can reduce insulin resistance, visceral fat, as well as reduce pigment from acanthosis nigricans. Semaglutide may be more effective, however we will have to wait for the studies. 
  2. Skin directed treatments with prescription medications by a medical dermatologist. Medical dermatologists at Cutis Dermatology in Brisbane can assist. Sydney patients are referred to the Skin Hospital Westmead or Darlinghurst for management. They may prescribe retinol, retinoids, vitamin D analogues as well as lactic, salicylic or glycolic washes. 

Laser & peels. Acanthosis nigricans respond poorly to lasers & peels. Our dermatologist will discourage you from trying these methods as we have extensive experience in this field. Pico, fractional & nano lasers have been used. They give marginal, if any improvements after a series of 3 to 6 sessions. The same applies to chemical peels. 

Can chemical peels be effective in treating dark underarms?

Chemical peels are marginally effective; however side effects are commonly seen in this area. The safest peels are salicylic acid or retinoic acid, however multiple sessions are required. TCA peels are high risks especially in darker skin types. 

Formulations of glycolic, lactic & salicylic acid washes are far safer, & can be effective in some cases. A good starting point is 2% salicylic acid wash by Neutrogena or 1.5% by Cerave, or better still the 7% glycolic acid exfoliating toner from The Ordinary. 

Though pico lasers are the most advanced pigment lasers, they are only useful in treating dark underarm pigmentation due to post-inflammatory hyperpigmentation. 

Can vitamin C help treat dark armpits?

Vitamin C can be marginally effective in some cases; however it can also make skin in the underarm area darker due to skin irritation. Learn more-

Firstly, vitamin C is undoubtedly one of the most powerful antioxidants & pigment correctors that is available as an over-the-counter serum. We use it to lighten pigmented patches primarily on the face (melasma, skin lightening, skin brightening, treatment of post inflammatory hyperpigmentation as well as an antiaging serum to reduce oxidation). The problem with vitamin C is that good formulations have a low pH, this makes it highly irritating, especially in flexural areas, namely the underarms. 

Here is how to overcome skin irritation if you are considering vitamin C to the underarm area/s.  

  1. Choose a low percentage formulation, L-ascorbic acid 5 to 10%.
  2. Wash the underarm area with a low irritation cleanser prior to application, always apply to dry skin. 
  3. Apply a thin layer of serum in the evening, starting every alternate night. 
  4. Wash the area with a low irritant cleanser (QV or Cetaphil) in the morning.
  5. Increase application amount & frequency as tolerated.
  6. Avoid other potential irritants such as retinol, retinoids, salicylic acid, glycolic acid, etc.

If you develop skin irritation due to overuse, your dark underarm patches may worsen, hence why we prefer other skincare products to treat this area. Less irritating ingredients include niacinamide & azelaic acid. 

How to use glycolic acid for dark underarms?

Learn more about how to use glycolic acid 7% exfoliating toner  from The Ordinary to treat dark underarm patches. 

Glycolic acid can help improve the appearance of dark armpits through several mechanisms:

  1. Exfoliation: Glycolic acid is an alpha hydroxy acid (AHA) known for its exfoliating properties. By gently removing dead skin cells from the surface of the skin, glycolic acid can help lighten dark underarm patches and reveal brighter skin underneath.
  2. Skin Brightening: Glycolic acid promotes cell turnover and stimulates collagen production, which can result in a more even skin tone and reduced appearance of hyperpigmentation, including dark underarms.
  3. Unclogging Pores: Glycolic acid can help unclog pores and remove built-up debris and impurities, which may contribute to the darkening of the underarm area.
  4. Enhanced Product Penetration: By exfoliating the skin’s surface, glycolic acid can improve the penetration of other skincare products, such as lightening agents or moisturizers, allowing them to work more effectively in lightening dark underarms. For example, AHA wash + retinol. 

To use the glycolic acid 7% exfoliating toner to treat dark underarms effectively, follow these simple steps:

  • Buy the 7% glycolic acid toner online. It costs less than $13. 7% is a good starting point, but if you have sensitive skin, consider a 3 to 5% formulation.
  • Cleanse the Underarm Area: Wet the underarm area with lukewarm water, then apply a small amount of the glycolic acid wash to your fingertips or a soft cloth. Gently massage the product onto the skin using circular motions for about 30 seconds to 1 minute.
  • Leave on Briefly: Allow the glycolic acid wash to remain on the skin for a brief period, typically 1 to 2 minutes. Avoid leaving the product on for too long, as prolonged exposure to high concentrations of glycolic acid can lead to irritation or sensitivity.
  • Rinse Thoroughly: After the designated time has passed, rinse the underarm area thoroughly with lukewarm water to remove the glycolic acid wash. Ensure that all traces of the product are removed from the skin to prevent irritation.
  • Pat Dry and Moisturize: Gently pat the skin dry with a clean towel and follow up with a moisturizer suitable for your skin type. Hydrating the skin after using glycolic acid can help prevent dryness and irritation.
  • Frequency of Use: Start by using the glycolic acid wash once or twice a week, and gradually increase the frequency as tolerated. However, be cautious not to over-exfoliate, as this can lead to irritation or exacerbate darkening.
  • Monitor Progress: Consistently use the glycolic acid wash as part of your skincare routine and monitor the progress of your dark underarms over time. It may take several weeks to notice visible improvements in skin tone and texture.

If you experience any signs of irritation, redness, or discomfort while using the glycolic acid wash, discontinue use for a few days, then recommence with less contact time. 

What about niacinamide for dark armpit-underarms?

Vitamin B3 or niacinamide can be effective in some cases of armpit darkening. This vitamin is much safer than vitamin C as it is less irritating to use. Look for a 10% formulation & use it in the evening to dry underarm skin. It can take up to 4 months before you see any differences. 

Niacinamide can help reduce armpit pigmentation through several mechanisms:

Inhibition of Melanin Production. Niacinamide has been shown to inhibit the transfer of melanin to the skin’s surface, which can help reduce the formation of hyperpigmentation. By regulating melanin production, niacinamide can help lighten existing pigmentation and prevent further darkening of the skin.

Skin Barrier Function: Niacinamide supports the skin’s natural barrier function, helping to maintain moisture levels and protect against friction. Niacinamide can improve overall skin health and resilience, which may help reduce pigmentation over time.

Antioxidant Activity. Niacinamide acts as an antioxidant, helping to neutralize free radicals. By reducing oxidative damage, niacinamide can help prevent the formation of dark spots & pigmentation.

Anti-Inflammatory Properties. Niacinamide has anti-inflammatory properties that can help calm irritated skin, reducing redness and inflammation associated with pigmentation.

How to treat dark underarms after laser hair removal or waxing?

Darkening of the underarms-armpits after laser or waxing can occur due to several reasons:

Friction and Irritation: Waxing involves pulling hair out from the root, which can lead to friction and irritation in the underarm area. This irritation may trigger inflammation and stimulate the production of melanin, resulting in temporary darkening of the skin.

Post-Inflammatory Hyperpigmentation (PIH). In some cases, waxing or lasers can cause post-inflammatory hyperpigmentation (PIH), which occurs when the skin responds to trauma or irritation by producing excess melanin. This can lead to dark spots or patches in the underarm area.

Chemical Sensitivity: Some individuals may experience a reaction to the ingredients in the wax or pre- or post-waxing products used, leading to irritation and darkening of the skin.

In most cases, the solution is simple- pico laser coupled with skin care products to reduce pigmentation can fade the skin in the underarm area within 3-6 sessions. Some cases are resistant to treatment (as pigment is super deep). 

The clinic who caused the pigment will usually pay for treatments to address the side effects. You may require legal representation if your provider refuses to acknowledge the side effects. 

*Our dermatologists may be required to provide a medicolegal report upon further questioning by a lawyer. Note: this report cost between $1500 to $2500 to generate, depending on the complexity of the matter. Medico Legal reports are not part of the initial consultation fee of $360 as they take 60 to 120 minutes. 

How to treat dark armpits after pregnancy?

Darkening of the armpits-underarms, also known as hyperpigmentation, is a common occurrence during pregnancy due to hormonal changes. Most cases settle within 12 months, some take longer. To treat dark underarms after pregnancy, consider the following tips:

Exfoliate Regularly: Incorporate gentle exfoliation with 7% glycolic acid toner  into your skincare routine to remove dead skin cells and promote cell turnover. This can help lighten dark spots and reveal brighter skin underneath. Another option is 2% salicylic acid wash. 

Use skincare products containing ingredients known for their skin-lightening properties, such as azelaic acid, niacinamide, vitamin C, liquorice extract, or kojic acid. These ingredients can help fade dark spots and even out skin tone when applied regularly to the underarm area.

Avoid Irritants: Refrain from using harsh deodorants, fragrances, or other products that may irritate the skin. Opt for gentle, hypoallergenic products to minimize irritation and promote healing.Our clinic can provide solutions for pigmentation after pregnancy including pico lasers & chemical peels for pregnancy induced melasma. 

What is the best deodorant to use if I have dark underarms?

Darkening of the underarms can be due to irritation of the area due to –

  1. Excessive sweating. 
  2. Chemicals. 

Here are the best antiperspirants & deodorants recommended by dermatologists. 

The best non-irritating deodorant may vary depending on individual preferences and sensitivities. However, some options to consider include:

Hypoallergenic Deodorants: Hypoallergenic deodorants are specifically formulated to minimize the risk of allergic reactions and skin irritation. Look for products labelled as “hypoallergenic” or “suitable for sensitive skin” for a gentler option.

Aluminium-Free Deodorants: Aluminium-free deodorants are formulated without aluminium salts, which can be irritating to some individuals. Look for products labelled as “aluminium-free” or “aluminium-free formula” to minimize the risk of irritation. 

Roll-On or Stick Deodorants: Roll-on or stick deodorants are less likely to contain irritating ingredients like propellants or aerosols found in spray deodorants. Opt for roll-on or stick formulations for a gentler application.

Alcohol-Free Deodorants: Deodorants containing alcohol can be drying and irritating to the skin, especially for individuals with sensitive skin. Look for alcohol-free deodorants to minimize the risk of irritation.

Fragrance-Free Deodorants: Fragrances can also be a common source of irritation for sensitive skin. Select fragrance-free deodorants or those labelled as “unscented” to reduce the likelihood of skin irritation.

If you suffer from excessive sweating (that is refractory to simple antiperspirants & or you suffer from skin irritation due to aluminium chloride hexahydrate use), a simple solution is Botox to the underarm area. This 3-minute procedure is covered under Medicare, it lasts up to 6 months & is highly effective in over 96% of patients. 

More here.

What is the best cleanser to use if I have dark underarms?

Cleaning the underarm area with the correct cleanser is important. Dermatologists endorse QV products as they are specially prepared for dry or sensitive skin. 

QV Gentle Wash is suitable for conditions such as eczema, dermatitis & dark underarm patches as it is fragrance-free and propylene glycol-free. It is pH balanced, colour free & lanolin free.

How to treat Ashy dermatosis that involves the armpit area?

Ashy dermatosis is a rare cause of dark underarms. This rash also affects the body, limbs & often the face. It is best treated by a medical dermatologist who may prescribe various drugs such as clofazimine or isotretinoin. 

Lasers are only successful in less than 50% of cases, even with the most technologically advanced picosecond lasers. It can take up to 4 months before results are seen, often requiring 3-4 sessions. Lasers are not a guaranteed way to fade pigment from Ashy dermatosis. 

*We can diagnose Ashy & provide a second opinion; however we do not get involved in medical management as this requires close follow up.

What are other types of lasers that can treat dark underarms?

The Melasma Clinic has access to over 40 lasers & energy devices. Picoway & Picosure Pro are by far the best lasers for dark underarms. 

We also have BBL, IPL & Q switch lasers. These devices are not as good as picosecond lasers. 

Can our dermatologists diagnose & treat dark underarms?

Our dermatologist can diagnose cases of dark armpits, however our Sydney clinic will not manage medical conditions such as acanthosis nigricans, Ashy dermatosis, post inflammatory pigmentation due to allergic or irritant contact dermatitis. If prescriptive medication or testing is required, we will refer you to the Skin Hospital in Sydney, or Cutis Dermatology in Brisbane. 

A SummaryTreating dark underarms

Dr Davin Lim | Dermatologist
The Melasma Clinic, Brisbane | Sydney

The working algorithm once a diagnosis has been made is easy to understand. The chances of success depend on the diagnosis. Ideally, the first point of contact is a medical dermatologist who can examine your underarm area and provide you with a rough working diagnosis or at least a differential diagnosis. This is especially important if the cause of dark underarms is uncertain as some cases require a biopsy. 

In short, for post inflammatory hyperpigmentation, the chances of fading dark underarm patches is high, providing the instigating inflammation has subsided & is quiescent. Examples include irritant contact dermatitis (from antiperspirants, friction or other causes). For contact dermatitis that persists, patch testing (again by a medical dermatologist) is required. Your dermatologist will test for possible allergies to fragrance, preservatives & other possible allergens via a European standard battery. Persistent cases may require special testing using key ingredients from your personal skin care routine. 

PIH due to friction (often due to excessive sweating or axillary hyperhidrosis) is easily treated with Botox. This treatment is covered under Medicare. Once sweating has decreased, we then use pico lasers to fade the pigment. Frictional dermatitis due to excess weight – high BMI is treated by weight loss & managed by endocrinologist & dieticians. 

PIH due to other causes such as pityriasis rosea inversa, flexural lichen planus, flexural psoriasis, Ashy dermatosis, CARP, & other rare flexural inflammation is managed by a medical dermatologist. I will be able to provide a comment but will not be involved in management as most cases require close review & prescriptions for topicals & systemic medication. Unusual cases may require a biopsy. 

For acanthosis nigricans (a very common cause of dark underarms), you will be referred back to your GP for management. The mainstay of treatment involves a multidisciplinary approach including physicians, endocrinologists, dieticians & medical dermatologists. Lasers & chemical peels have a very low success rate. 

This leaves genetic causes of pigmentation, which can affect other areas of the body & face. We term this as constitutional pigmentation. Other affected areas include the eyes (dark circles that are continuous with the upper & lower eyelids in a ‘c’ pattern) & perioral hyperpigmentation (affecting the mouth area). Pigmentary demarcation lines are also genetic in origin & may involve the face & trunk. Genetic cases are hard to treat. Lasers can be marginally effective in some, but not all cases. Pigment is recurrent (some may have variable remission of months to years, but it is easy to predict). 

Here’s my advice without the fluff, if you have dark underarm patches due to post inflammatory hyperpigmentation, it is worth treating with lasers only if the inflammation has been treated & in remission. If you have dark patches due to other causes, you are best treated by a medical dermatologist using creams & in some cases tablets. Lasers for all other conditions play a very small role, with limited success.