It is defined as a very general term used to describe a whole range of skin problem associated with irritation.
Definition of sensitive skin
Sensitive skin is a lay term. It is not a diagnosis. The term is used broadly to describe
- any skin situation where it has a much decreased tolerance compared to the general population,
- to substances be it irritating or not, that it comes into contact with.
- These substances encompasses the commonly used items on a daily basis.
- There are the
- moisturiser and any other
- personal care toiletry and products.
The skin sensitivity is a very common problem found among the general population.
Its incidence is very high.
- In the various research studies, it was found that more than half of the female population and,
- nearly half of the male population have the sensitive skin problem. As you can see the figure is certainly big. In another word,
- almost half of the general population has this sensitive skin issue.
My own case example. When I was much younger, I have a very good flawless skin. However, today, I get itchy skin for no reason. A warm shower may end up getting redness and itchy skin. A simple squeezing and scratching can initiate a whole day of rash and itch. True, at different ages, our body also experiences different threshold of succumbing to irritation initiation. As you age, the tolerance is generally reduced. Sorry for the folks who are elderly!!
Sensitive skin presents in 2 major categories. There are 10 different types of Irritant Contact Dermatitis which are described here with:
- Sensitive skin with subjective symptoms: in 8 types of Irritant Contact Dermatitis, ICD, they always have symptoms of stinging, burning and most important of all is itching sensation.
- Sensitive skin with/without visible skin changes: here is a smaller group.
- There are 2 types of ICD;
- This mean there may be NO SIGN of skin changes seen by our naked eye.
- In the event there are sign of any skin changes,
- the most important of all is the skin redness.
- Other sign of skin changes will includes
- peeling skin,
- scaling skin,
- bumps, and
- hives with swelling of the skin.
- When the most important sign is not there, there may just be feeling of itchiness.
People usually refer to the face when talking about the sensitive skin, instead of the body skin.
- A product that is well tolerated by body skin
- may usually cause irritation and rashes if applied to the FACE. This is because the face skin is more delicate and thin.
Areas affected other than the face:
The other sensitive area includes the
- eyelids which are especially sensitive.
- groin and genitals may also be more sensitive than other areas.
This is because all these areas are made up of thinner skin that can irritate easily.
Causes of sensitive skin
There are a number of commonly recognised medical causes of sensitive skin
- Top in the list is Irritant contact dermatitis (abbreviated as ICD)
- Allergic contact dermatitis forms the 2nd largest group
- Contact urticaria
- Physical urticaria and dermographism
- Aquagenic pruritus
- Dry skin
- Another big group is Eczema/dermatitis of any type
- Cutaneous mastocytoses
Each of these causes will be discussed in details below.
ICD is defined as an inflammatory response of the skin to an externally applied factors. There is no requirement to have any prior sensitisation, i.e., it is not due to allergy.
Examples of such agents/factors include:
1. Skin irritants, of which being wet is of utmost important. Many chemicals can easily cause skin irritation if exposed long enough. However, it is usually a combination of several mild irritant agents/factors accumulating up in order to bring about a true ICD.
2. Environmental factors such as heat, cold, low humidity and ultraviolet light can all precipitate
3. Irritating body fluids such as sweat, urine and faeces, when contact is sufficiently long enough
4. Mechanical factors eg friction, pressure, vibration and occlusion.
5. However, the host factors also plays an important role to influence overall susceptibility. These factors includes the age, sex, skin site and history of any eczema. NOTE: in this case the irritant is prolonged frequent water contact depriving the intact skin of protective barrier.
(A) Irritant contact dermatitis (ICD)
The term sensitive skin, is most often refers to a form of irritant contact dermatitis.
ICD is defined as:
- an inflammatory response of the skin to externally applied factors.
- There is no requirement to have any prior sensitisation, i.e., it is definitely not due to allergy.
Here are some examples of such agents/factors which may include the followings:
- Skin irritants.
- It is surprising to note that, just being wet is itself an important irritant. Why is it so?
- This is because the wetness cause the protective sebaceous oil being wash off exposing the skin to attack.
- Many chemicals can now easily irritate the exposed skin layer.
- However, it is usually a combination of several milder irritant agents/factors collectively that keeps on adding up in order to bring about a true ICD.
- Environmental factors such as
- low humidity and
- ultraviolet light (UVA & UVB Light) can all precipitate
- Irritating body fluid secretions such as
- urine and
- faeces, which are all very highly toxic and irritating, can excoriate the skin, when contact is sufficiently long enough
- Mechanical factors e.g. such as
- vibration and
- However, the host factors also plays an important role to influence susceptibility. These factors includes
- skin site and
- history of eczema.
2 groups described earlier are listed again, here includes:
- Of these, 8 are present with clinically visible skin changes.
- 2 types of Irritant Contact Dermatitis, ICD, show no visible skin changes. This is further divided as below;
- a) subjective,
- b) sub-erythematous.
a) Subjective or sensory irritation, is also known as sensorineural irritation,
- This is characterised by various sensory discomfort such as
- tingling or
- These symptoms are present but without any, which is be it clinical or histological, evidence of inflammation.
- Involvement of nerves and blood vessels is the contributing factor to the development of the symptoms that we see
- Lactic acid and propylene glycol found in the cosmetic agents are the common causes of this symptom.
- The threshold for developing these symptoms,
- following an application of these chemicals to the skin, varies between individuals and,
- this does not correlate with the patient’s susceptibility to other forms of skin irritation.
- The onset is usually acute.
- Avoiding the irritant or, using personal protective equipment such as gloves is very effective in prevention
- frequent use of good amounts of moisturiser on the skin usually results in a better outcome.
b) non-erythematous irritation, which is also called sub-erythematous irritation.
This form of irritation shows no visible sign of skin changes.
This form of ICD, Irritant Contact Dermatitis differs from subjective irritation as described below:
- the person experiences similar symptoms (meaning itch, stinging, burning), BUT no rash is visible at all
- However, there are changes of inflammation.
- The changes are only at the cellular level, non visible to the naked eye.
- This will only be seen in the skin biopsy histopathological examination, HPE.
- It often develops slowly, and
- various discomfort is being experienced with multiple chemical ingredients that form the irritants.
- Cocamidopropyl betaine & coconut diethanolamide, are both recognised causes of this 2nd type of ICD.
- Both are commonly used ingredients in any cosmetics.
- However, the outcome with this form of ICD is variable.
Allergic contact dermatitis (ACD).
1. Allergic contact dermatitis is a skin reaction that follows, after the development of an allergic response to any allergens.
2. The skin reaction is an allergic response to an externally applied agent or stimuli and, is less common than irritant contact dermatitis.
3. This type of reaction develops with an increasing intensity over time, over multiple repeated insult in the course of history. NOTE: in this case shown above, the offending allergen is natural rubber latex.
(B) Allergic contact dermatitis (ACD)
- Allergic contact dermatitis is a skin reaction, following the development of an allergic response by the skin.
- The skin reaction is an allergic response to an externally applied agent and, is again less common than irritant contact dermatitis.
- It typically develops with an increasing intensity with time, over multiple repeated insult on the skin, in the course of history.
- Some chemicals are known to commonly cause an allergic reaction but, usually it is only in some occasional or rare individuals that such a reaction ever develops.
- The causative agent can be identified through the use of patch testing.
(C) Contact urticaria
Contact urticaria is a form of skin hives, being formed after triggered by skin contact with an agent, which is pretty common. The hives is quickly accompanied by swelling and redness which only resolves over hours.
It can be confirmed by prick testing.
There are 2 types of contact urticaria: namely,
- irritant and
- allergic forms of contact urticaria.
Rosacea is a common facial skin condition, which is characterised (most important is flushing) by some, or all of the following clinical features:
1. Foremost important, is a must to have flushing and blushing
2. Persistent redness or having broken capillaries (called telangiectasia)
3. Thin and often very transparent skin, able to see through the capillaries
4. Acne-like rash, of appearing bumps and pimples.
5. Localised facial swelling.
The skin sensitivity in this condition can present as, skin redness or irritation after application of a cosmetic. NOTE- the offending agent shown here is the cosmetic cream.
Rosacea is a common facial skin condition. This is characterised by,
- the most important of which is non other than flushing.
- It is frequently accompanied by the following characteristics or clinical features such as:
- Foremost important is, it is a must, i repeat, a must to have flushing and blushing
- Persistent redness and or broken capillaries, also called as telangiectasia
- Thin and often transparent skin, been able to see through the capillaries
- Acne-like rash of bumps and pimples
- Localised facial swelling
- Skin sensitivity
The skin sensitivity can present as
- redness or
- irritation after an application of some cosmetic.
- Such a cosmetic is usually a routine tried and used toiletry or skin care products.
- It is noted that All the previous use of such product, was uneventful but
- not anymore for no apparent reason.
- It is not known why it is the case.
(E) Physical urticaria and dermographism
Physical urticaria refers to the presence of hives triggered or formed, by a
- physical event such as pressure, heat, cold or even vibration.
Thus the person may experience a red rash over the body while taking a hot shower for example. In this case, it is a reaction to the hot temperature of the water, and not to the water per se, and such a rash usually resolves within an hour after cooling.
Dermographism literally means:
- to be able to write on the skin.
- The written line on the skin becomes raised and red in colour.
- The skin becomes red and puffy after a scratch.
(F) Aquagenic pruritus
In aquagenic pruritus, the skin becomes itchy soon following contact with water of any temperature, be it hot or cold or in room temperature.
Dry skin from any cause is irritable and sensitive. Skin may be dry due to:
1. genetic reasons i.e., ichthyosis, a fish-scale skin. This is a dry scaly skin condition.
2. Aging factor. All aging causes dryness of skin due to decreased sebaceous gland activity.
3. Aging per se —-> dry skin –> itchy sensitive skin
4. environmental factors such as low humidity, like dry environment in air-conditioned room, continental Europe, US and Asia.
5. Excessive washing washes away the protective skin covering layer. NOTE: Aging per se is a MAJOR cause of skin dryness.
(G) Dry skin
Dry skin from any cause is irritable and sensitive. Skin may be dry due to:
- genetic reasons i.e., ichthyosis, a fish-scale like skin. This is a dry scaly skin condition.
- Aging factor. All aging causes dryness of the skin due to decreased sebaceous gland activity.
- Aging per se —-> gives rise to dry skin –>lead to itchy sensitive skin
- environmental factors such as low humidity, like
- dry environment in air-conditioned room,
- continental Europe, US and Asia.
- Excessive washing, removing away the protective skin covering layer.
- general health issues such as thyroid disease. They affect sebaceous gland activity and skin covering.
- any condition the decrease skin’s oil gland activity and skin covering.
Dry skin tends to be itchy, especially if in an overheated weather or environment.
In its attempt to relieve the problem of dry skin, it is not hard to:
- understand that the patient is often attempting to use many products topically to try to improve this.
- Thinking that more is better.
- The flip side is that the well intention effort brings too many skincare ingredients into contact with the skin.
- This is not difficult to see why it is asking for problem. Too many ingredients may therefore giving a higher chance to develop a contact dermatitis.
Eczema skin is usually itchy with a visible rash, which usually can further react to water, temperature, humidity and other environmental factors.
Thus the presence of a second problem such as an irritant or allergic contact dermatitis, to an agent/ product being applied to the skin may be overlooked.
Eczema of any type is a well-recognised predisposing major factor, for the subsequent development of irritant contact dermatitis.
All forms of eczema or dermatitis, which commonly includes the problem skin like
- the atopic dermatitis,
- seborrhoeic dermatitis,
- venous dermatitis,
- asteatotic dermatitis, etc., –> can result in a very sensitive and, easily irritated skin.
The one and only one most important factor lies in the–> lost of intact skin barrier, allowing offending external irritating agents or factors to penetrate through the protective skin covering, the friendly sebaceous oil layer.
Eczema skin normally always comes with itchiness of skin and, is usually accompanied with a visible rash.
- This skin rash can further react to other factors like
- the water which looks so benign but yet powerful actor,
- temperature and also
- many other external environmental irritant agents.
- So, the presence of a 2nd problem, such as an irritant or allergic contact dermatitis, to a product or cosmetic being applied to the skin can easily been overlooked.
Put it another way,
- even the smartest doctor can be tricked
- into thinking eczema as the only cause without realising the ICD!
- Eczema of any type, is a very well-recognised predisposing or aggravating factor, for the development of irritant contact dermatitis, which is the number one common dermatitis.
Skin sensitivity may take the form of a reaction to sunlight, which is also called photosensitivity.
- This problem of over sensitive to light, can present as either sunburn, blisters, or hives.
- Sometime, it may present as other sensory symptoms such as tingling sensation.
- There are many sub-types of known photodermatoses.
(J) Cutaneous mastocytoses
Cutaneous mastocytosis is a very rare group of conditions.
- Here, there are present of an excessive number of mast cells found in the skin.
- This mast cell can easily release copious amount of histamine following/after
- heat, etc.
- The released histamine results in skin
- puffiness and
- perhaps even blistering in severe cases.
- The most common type of mastocystosis is called urticaria pigmentosa.
How is sensitive skin diagnosed?
The sensitive skin may be diagnosed clinically most of the time. Occasionally, for any objective evidence, this may need/require additional tests, commonly performed are skin biopsy or patch testing.
Proposed mechanisms of sensitive skin
Skin irritation is a complex biologic event involving a variety of different receptor types. This is occurring at the cellular and sub-cellular level.
Treatment of sensitive skin
Principle of sensitive skin treatment is not difficult to understand.
The best is still by conservative medical means. Dr David Ling with 25 years of aesthetic medicine experience, with his aesthetic clinic, Clinic Laser and Cosmetic Surgery Ling, can use not just medicine approach, but also a lot of patient education is required. No amount of treatment is complete without active informed patient participation.