The sebum (secretion from the glands of the skin) production increases;which plugs the tubes. This causes growth of acne bacilli which form an enzyme (lipase) causing an increased production of free fatty acids which are irritant to the skin. These bacteria also release some factors (chemotactic factors) that cause inflammation. The face, neck, chest, shoulders, and back are most commonly involved. Mild acne is characterized by an oily or greasy skin with closed or open, small sized papules (comedones); in moderate acne, papules or pustules are accompanied by inflammation. In severe form, nodules with inflammatory cysts are formed which leave a scares. Pus-discharging abscesses are rare.
Non-Drug Therapy: Avoid drugs like corticosteroids, androgens, iodides, bromides, and androgenic progestins found in some oral contraceptives. If oral contraceptives are to be taken, mini pills should be avoided. Select the one which has a higher ratio of estrogen to progestins. This minimizes the androgenic effect of progestins. Avoid humid environments, occlusive cosmetic oils, and greases.
Diet does not seem to play any role in acne. Minimize the oiliness by washing the area 2 to 3 times daily. Scrubbing with abrasive substances is not advisable as it may damage the delicate opening of the hair follicles through which the sebum flows. Mild soaps are enough. The comedones (blackheads) should never be manipulated or scratched, even if there is irritation. This leaves scars causing disfiguration. At least 4-6 weeks time is needed for improvement to occur. Lesions over shoulders, chest and back take longer time than this.
Various measures like reducing the sebum output, action on the follicles, action on propinonobacterium acnes, control of infection, have been tried. Most of the preparations contain sulphur, resorcinol, salicylic acid or benzoyl peroxide alone or in combination, but they do not have any response on acne. The treatment requires regular use of effective medicines under the instructions of a physician.
Liquid cleansers, lotions, and creams containing abrasive particles for removing surface debris, foe e.g., aluminium oxide, sodium tetraborate, polyethylene; drying agents such as alcohol or acetone; or peeling agents like sulphur, resorcinol, benzoyl peroxide, and salicylic acid are used for mild acne. Hot compresses may be as effective as some of the agents mentioned above.
Small amount (pea size) of Tretinoin (Retino-A 0.05%) can be applied two times in a week initially at night (to avoid irritation). Then gradually it can be applied every night and left for about 20 minutes before the face is washed. Tretinoin is a vitamin-A derivative and prevents plugging of follicles. Usually it is used for 3-4 months.
Adverse Effects and Precautions: It is an irritant drug and should be applied strictly as per instructions. The skin becomes red within 48 hours and begins to peel. It should be applied once at night and the sun should be avoided to reduce irritation. It should not be applied on any part of the skin having eczema. Its application on areas near the corners of the mouth, nose any part of should be minimised. Other peeling drugs like sulphur, resorcinol, salicylic acid, and benzoyl peroxide may enhance irritation and should be avoided. Do not wash the face more then 2 to 3 times a day. Allergy to this drug is rare.
Benzoyl Peroxide (Pernox gel 2.5% persol forte 10%) is a water based formulation (alcohol free) so irritation is less. It causes peeling of unwanted skin cells.
Adverse Effects and Precautions: Due to its peeling effect on the skin, it causes local irritation. If the irritation is severe, the dose and frequency of use may be reduced. It is applied for 15 minutes on the first evening. The duration of application is increased by 15 minutes every day until it is tolerated for 2 hours. It may, thereafter, be left on overnight. A possible allergic reaction may occur with this drug. The chances of allergy increase if it is applied under occlusive dressings or patches. Tretinoin 0.1% cream