Acnetrin

Indications

Tretinoin is mainly used on the skin to treat acne (blackheads, whiteheads and pimples) and, in some products, to improve fine wrinkles, rough skin and dark spots caused by sun damage. A capsule form is used in hospitals, together with other treatment, for a type of blood cancer called acute promyelocytic leukaemia.

How It Works

Tretinoin is a form of vitamin A. On the skin it speeds up the turnover of skin cells, unblocks pores and stops new blackheads forming. In leukaemia, it helps abnormal blood cells mature into normal cells.

Dosage and Administration

Cream or gel: once a day at night, wash the face with a mild cleanser, wait 20 to 30 minutes until the skin is fully dry, then apply a thin, pea-sized amount to the whole affected area. Avoid the eyes, lips, corners of the nose and broken skin. Start with the lowest strength or every other night if the skin is sensitive. Improvement usually takes 6 to 12 weeks, and acne may look worse in the first few weeks. Wash hands after use. Capsules: given only under a cancer specialist, as prescribed.

Interactions

• Using other drying or irritating skin products at the same time, such as Benzoyl Peroxide, Salicylic Acid, alcohol-based toners, scrubs or medicated soaps, increases irritation; ask the doctor how to space them.
• Other medicines that make the skin sensitive to sunlight add to the risk of sunburn.
• Capsules: Ketoconazole and similar antifungals raise tretinoin levels, and tetracycline antibiotics increase the risk of raised pressure in the skull.

Contraindications

Allergy to tretinoin or any ingredient; eczema, sunburn or broken skin in the area to be treated; pregnancy or planning a pregnancy. Capsules must never be used in pregnancy.

Side Effects

Skin: redness, dryness, peeling, stinging or burning, and a temporary flare of acne in the first weeks; the skin becomes more sensitive to sun, wind and cold. Capsules can cause headache, dry skin and lips, bone pain and raised blood fats.

Get urgent medical help for severe swelling, blistering or crusting of the skin, or signs of a serious allergic reaction. If taking capsules, get urgent help for fever, breathlessness, chest pain, rapid weight gain or swelling, or a severe headache with vision problems.

Pregnancy and Lactation

Tretinoin capsules cause serious birth defects; reliable contraception is required before, during and for some time after treatment, as the doctor advises. Tretinoin on the skin should also be avoided in pregnancy and by women trying to become pregnant. While breastfeeding, do not apply it to the breast area, and ask a doctor before using it; do not breastfeed while taking capsules.

Precautions and Warnings

• Use a broad-spectrum sunscreen every day and avoid strong sun and sunbeds.
• Do not wax, use hair-removal creams or have chemical peels on treated skin.
• Using more or applying it more often does not work faster and only causes more irritation.
• Do not use with other vitamin A medicines unless the doctor advises.

Overdose

Too much on the skin causes marked redness, peeling and discomfort; stop for a few days and restart less often. If it is swallowed, or too many capsules are taken, get medical help.

Therapeutic Class

Retinoid (vitamin A derivative), used as an anti-acne agent and, as capsules, an anticancer agent.

Storage

Store below 30°C, away from light and heat, with the tube tightly closed, out of the reach of children. Some gels are flammable; keep away from open flames.