Adult acne first develops in the twenties or later. The strict definition of Adult Acne is Acne that first develops after 25, but definitions vary slightly.
Adult acne is common. In America 50% of adult women has Acne in their twenties, 35% in their thirties, 26% in their forties and 15% in their fifties.
Teenage and adult acne is due to excessive sebum production from oil (sebum) glands. The increased sebum production leads to changes in the mouth of the hair follicle, the infundibulum, which enlarges and becomes plugged with open comedones (black heads) and closed comedones (white heads). A bacterium that normally occurs on the skin, Propionibacterium Acnes, proliferates in the excess sebum, which leads to inflammation, pimples and worse blackheads and whiteheads via biofilm formation.
Adult Acne is common around the jaw line area and is mostly inflammatory (pimply), whereas teenage acne occurs more in the T-panel and is often a mix of inflammatory lesions (pimples) and comedones (blackheads and whiteheads).
In the teenage years increased sebum production is due to the natural surge in hormones that occurs at puberty. This clearly cannot be the cause of Adult Acne.
The causes of Adult Acne include unnaturally increased testosterone levels from a variety of sources, a genetically increased sensitivity to testosterone, increased insulin-like growth factor 1 (IGF-1) that mimics the effect of testosterone, oral medication, cosmetics, smoking and possibly raised insulin levels.
Causes of unnaturally increased testosterone levels:
- Polycystic ovarian disease
- Overproduction of testosterone from a tumor of the ovaries or testis
- Overproduction of testosterone from adrenal gland hyperplasia or an adrenal gland tumor
- Overproduction of testosterone in the skin, due to stress induced increased release of Corticotrophin Releasing Hormone (CRH) from the brain
- a Relative excess of testosterone versus estrogen around the middle of the menstrual cycle
- a Relative excess of testosterone versus estrogen around the menopause
Causes of increased Insulin-like growth factor (IGF-1):
- High glycemic index foods causes a spike in IGF-1
Oral medications that can cause Adult Acne:
- Oral Contraceptive pills (OCP’s) that contain 1st generation progestins, like norgesterol
- OCP’s that contain 2nd generation progestins, like norethindrone, ethynodiol diacetate, and levonorgestrel
- OCP’s that contain third generation progestins, like norgestimate or desogestrel
- Vitamins B2,B6,B12 and D2
- SSRI’s, like Prozac
- The Tuberculosis drugs, Isoniazid and Ethionamide
- The epilepsy drugs, Phenytoin and Phenobarbital
- Glucocorticosteroids, like Prednisone
- Anabolic steroids
- Corticosteroid creams and ointments
- Iodides and Bromides. Iodides are found in cold and asthma preparations, kelp and vitamin & mineral supplements. Bromides are found in sedatives, analgesics and cold remedies
Other causes of Adult Acne;
- Cosmetics, especially occlusive petroleum bases moisturizers
- Increased insulin levels (hyperinsulinemia) can stimulate sebum production.
Often, what appears to be Adult Acne, is in fact another condition mimicking acne. These Acne mimics include:
- Perioral dermatitis
- Acne Rosacea
- Gram negative folliculitis
- Pseudofolliculitis barbae
- Sebaceous Hyperplasia
The diagnosis of Adult Acne requires a detailed history and careful examination. In addition to Adult Acne an irregular or absent menstrual cycle, excess hair on the face and body (hirsutism), loss of hair from the scalp (androgenetic alopecia), oily facial skin (seborrhea), a milky discharge from the breasts (galactorrhea), enlargement of the clitoris (cliteromegaly), a coarser voice and infertility are all signs of raised testosterone levels.
If the diagnosis is Adult Acne the next step is to identify and treat any underlying cause. If there is an identifiable cause for the Adult Acne, eliminating it will most likely clear the Acne.
Laboratory blood tests for FSH & LH (brain/pituitary gland origin), DHEA-S (adrenal gland origin) , Free Testosterone & Total Testosterone (ovarian origin), Prolactin (brain/pituitary gland origin), SHBG (liver origin), delta-4-androstenedione (adrenal gland origin), 17-hydroxyprogesterone (adrenal gland origin) and insulin might be requested. In women blood tests must be done within a few days of menstruation, when hormonal levels are naturally at their lowest, to avoid confusing results and women should also not be on the oral contraceptive pill. Abnormal hormone values might require closer examination of the ovaries, adrenal glands or pituitary gland.
Oral medication, vitamin supplements and cosmetics might be stopped or changed. Adult acne patients need to stop smoking. A low glycemic index (low carbohydrate/high fat – LCHF) diet to lower IGF-1 release and insulin levels might be required. Lower stress levels, to reduce Corticotrophin Releasing Hormone (CRH) levels, could be helpful.
Some patients will have no identifiable cause for their Adult Acne. Also, patients that have eliminated possible causes of Adult Acne, might still get Adult Acne. These patients will require general anti-Acne therapies, as used for Acne in puberty.