Dr Phil Kieran: How can we stop our daughter’s painful skin infections?

Hidradenitis suppurativa is also known as acne inversa and is a recurring condition 

Dr Phil Kieran: "When shaving it is a good idea to clean the skin first with a gentle soap and hot water. This cleans the skin and softens the hair making it easier to cut. Secondly cut in the direction of hair growth. Many of us are tempted to cut 'against the grain' to achieve a closer shave — however this has a much higher risk of causing skin irritation."

My daughter is 16 and has twice developed small painful cysts in her armpits which needed to be treated with antibiotics. I’ve recently read about a chronic skin condition called hidradenitis suppurativa (HS). Is it possible that she has it?

Skin infections, particularly in hair-bearing regions, are quite common. There are many causes for these episodes and if you have heard of HS, it can certainly be a very scary prospect. A relatively recent study suggests approximately 1.4% of the population have this condition, (Delany E, 2018) so chances are high that there is a different cause to your daughter’s cyst.

HS, also known as acne inversa, is a condition where you get inflammatory cysts forming on area of the skin which contain apocrine sweat glands. These are the sweat glands found in the armpits, groin, between the buttocks, and under the breasts (Irish Skin HS, 2025).

HS is a recurring condition, which means the episodes happen repeatedly.

In severe cases, this causes scarring. The damage to the skin is a vicious circle where the damaged skin is more susceptible to infection causing even more damage. Moderate or severe HS is something that should be treated under medical supervision but it can usually be controlled.

Folliculitis which is a bacterial infection of the hair follicle is much more common than HS and can look almost the exact same (Dermnet NZ HS, 2025). The main difference here is there is often a specific cause that can be identified and avoided, which means the condition doesn’t tend to cause long-term issues.

The most common cause for these types of infections is injury to the skin, which then allows bacteria to get into the follicle and cause infection. This can be caused by friction such as overly tight-fitting clothing or by small cuts or irritation to the skin caused by shaving.

If this is the cause, a few simple tricks can dramatically reduce the risk of infection.

Firstly, when shaving it is a good idea to clean the skin first with a gentle soap and hot water. This cleans the skin and softens the hair making it easier to cut.

Secondly, cut in the direction of hair growth. Many of us are tempted to cut ‘against the grain’ to achieve a closer shave — however this has a much higher risk of causing skin irritation.

Thirdly, razor blades should be sharp. This means if you feel the blade starting to drag on the hairs rather than cutting them it is time to change/sharpen the blade (AAD Skin Care basics Razors, 2025).

It is also a good idea not to share blades for many hygiene reasons but also so you know how long it has been in use for and when it needs changing.

By avoiding skin breakage and/or following the advice above, it is likely your daughter will stop getting these infections. If she does have HS, this advice will help but won’t stop the cysts reappearing and medication may be necessary. I suggest seeing your GP about how best to treat her condition.

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