> Oily, combination and acne prone skin cleansers, moisturizers and treatment

Diagnosis

Oily skin is recognized by large, visible pores with excessive secretions. Sebum production shows large amounts of cholesterol and triglycerides. Excess sebum has been one of the most known factors involved in pathogensis of acne. The trigger in excess production of various oils could be androgens especially dihydrotestosterone or other hormonal imbalances. Progestrone because of its activity on five-alpha reductase can inhibit formation of dihydrotestosterone leading to less oil production at the skin level. 5-alpha-reductase has two subtypes. Type 1 seems to be responsible in sebaceous glands and converts testosterone to DHT. Type 2 is affected by Finasteride and also in male pseudohermaphrodism who show less DHT. Effect of Zileuton, inhibitor of 5-lipooxygease and retinoids in reduction of sebum in the skin. Very distinct effect of inhibitors of cyclooxygenase and lipooxygenase pathways on sebaceous glands activity. Inhibitors of cyclooxygenase such as Indomethacin by reducing prostaglandins E2, F2 can show sebotrophic properties. while inhibitors of lipoxygenase such as Zileuton can reduce sebum and may be used in acne and rosacea.

Another regulatory factor on sebaceous glands is neuromediators such as substance P. Its effect to increase sebum production in stress conditions is more evident.

Treatment

Oily skin in severe cases of acne could be treated with anti androgens such as cyptroterone acetate. However, in mild to moderate cases this is not recommended because of the implicated side effects. Retinoids are other first hand drugs used for treatment of oily skin and acne. They reduce sebum production and hypercornification of sebaceous ducts. Other keratolytic agents such as salicylic acid, azelaic acid and alpha hydroxy acids may be used. Important point to mention here is by inducing dryness over the skin, sebaceous glands are stimulated to produce more oils such cholesterol, wax esters and squalene. Indeed this is what we experience by using alkaline soaps, alcoholic cleansers and many other oil free products. It seems use of cleansers and moisturizers containing oils similar to sebum may reduce overproduction of sebum. Zileuton is another drug which may treat oily skin by inhibiting production of leukotrienes D4 and E4. However, Zileuton do not seem to affect acne in severe cases. Inhibitors of cyclooxygenase pathway may be sebotrophic and increase oil production at epidermis. This may be an advantage in aging skin and their use in anti aging products may be considered.

Products and oily skin care

They hype of using oil free products for acne patients, oily or combination skin may be counterproductive. These products tend to be stimulatory to sebaceous glands and overproduction of sebum. Certain oils such as squalene available in shark cartilage oil, olive oil ( to much less extent) and omega 3,6 fatty acid containing oils such borage and evening primrose oil, Jojoba oil because of its similarity to sebum waxes may be beneficial and reduce hyper functioning sebaceous glands.

Cleansers

It is frequently heard about disadvantage of alkaline soaps and alcoholic cleansers because any change in pH could be an stimulation to sebaceous glands. To control body oily skin use of pH balanced shampoos and body washes is recommended instead of soaps and alkaline pH shampoos. Cleansers with a pH around 4.5-6 are best tolerated by sebaceous gland since they are very similar to pH of the sebum. Acidified cleansers containing nutritious oils may also control sebum overproduction. Oil free cleansers may have a detrimental effect.

Moisturizers

The best moisturizers for oily and combination skin should provide the skin with essential fatty acids and nutrients similar to sebum content. This includes cholesterol, triglycerides, wax esters and squalene. This down regulate sebaceous glands and has an inhibitory effect on sebum secretion. It is commonly stated that oily complexions should use oil free products. It is crucial to recognize comedogenic and pore clogging moisturizers and moisturizers containing nutritious oils similar to sebum content. Many moisturizers contain fats which may accumulate at skin pores and start a comedone, which is an acne precursor. These should be avoided in combination and acne prone skin. In contrast moisturizers containing linoleic and linolenic acids can provide the skin with essential nutrients which control sebum production.

| American Academy of Dermatology | Dermatology Online Journal | Sebaceous Glands | Dermatology Health Guide | Sebaceous follicle Carcinoma | Targeting IL-18 for treatment of etopic dermatitis | Role of nicotinamide in treatment of acne |

How to treat enlarged pores:

Oily skin is recognized by enlarged pores. This is a compensatory mechanism by the skin to increase its secretions. As we discussed earlier sebaceous glands under influence of androgens enhances its fatty secretions which are limply by propionate acmes. One way of influencing epidermis to tighten its pores is by affecting its secretions. Essential fatty acids are among the first modalities which contribute to inhibition of sebaceous glands by down regulation. If we can provide the skin with essential fatty acids we force the sebaceous glands to decrease its oil production. There are other factors which also stimulate these glands to provide more secretions. Any change in skin pH is an stimulation to sebaceous glands. Alkaline soaps are avoided in acne patients for the same reason. Any therapeutic intervention for acne should consider acid mantle of the skin. Most alcohol containing cleansers even those containing benzoyl peroxide can cause more sebum production by the same mechanism.

Keratolytic agents such as salicylic acid and retinoic acid are other treatments in reducing skin's pore size. These agents cause hyperkeratinazation and increasing cell turn over at epidermal level.

Skin oxygenation and deep pore cleansing has been associated with reduced size in skin pores by mechanism not very well explained. Among essential oils rosemary is suggested with such a property. Further research is called to prove this point.

Certain plant species also have demonstrated pore tightening effects. Rosemary, thyme and sage have been used for their control over sebaceous gland secretions. The mechanism by which they function is not quite understood, however, their effect in increasing microcirculation may be involoved. Their regulatory effect through inhibition of inflammatory cytokines may be another explanation for their contribution to tighten the pores.