Antibiotic Resistant Acne

Florence Barrett-Hill

In the last installment in this series, we discussed acne produced through natural causes and this is different to that of toxic origin. It is less common, but certainly around and unfortunately increasing in frequency.

This type of acne can occur from both the side effects of medications, (antibiotics, cortisone and tranquillisers) occupational causes, and self-infliction.
Establishing cause is the secret with this type of acne, as simply removing the cause generally guarantees some improvement.

Substances to be avoided and to be aware of during your consultation process

  • medication
    Some forms of acne can occur from the side effects of medications


  • Testosterone
  • Barbiturates
  • Amphetamines
  • Chlorine, tar and other petro-chemical compounds
  • Synthetic red or orange pigments (DC Reds are comedogenic.
  • Ultraviolet Radiation
  • Harsh drying substances
  • Free Fatty Acids.
  • High humidity/humectants

Antibiotic Resistant Acne

Antibiotics are commonly prescribed by Physicians to help treat acne by attempting to reduce the levels of P acnes bacteria. The resulting reduction in bacteria will consequently lower the rate of conversion of triglycerides to FFAs, thus decreasing the inflammatory response.
As this approach only treats the symptoms, and not the true cause of the condition, it can have limited effect, and with long-term use cause compounding problems.

Unfortunately, the use of antibiotics to treat severe acne can lead to the development of antibiotic resistance in the bacteria that further aggravate the skin condition.

Like many bacteria that have been over treated with antibiotics, the P acnes have developed many strains and a resistance to one or more common antibiotics.
It is the development of these many antibiotic resistant strains (Over 153) that render many antibiotics ineffective if used long term.
There is a great deal of literature on the Internet regarding antibiotic resistant bacteria with the American FDA website a good place to start your research.

Because FFAs would be considered a foreign body within the gland, they trigger an inflammatory process.

Understanding how antibiotics work is also very interesting, however for all their good, they dont neutralise the free fatty acids that ultimately cause the inflammation.
Because FFAs are pro-inflammatory, is makes sense that this would be the best place to start a treatment, rather than destroy or reduce a useful bacteria that plays a major role in the first line of skin barrier defence and not the primary causative agent of the acne to begin with.

Hormonal Mediated Acne

We know hormones play an important role in skin physiology, but how big a role do they play in acne?
The term Hormonal Mediated Acne can refer to acne that occurs because of hormonal changes within the body, accordingly I have written a brief and concentrated update on the hormones we often read about and the role that each one plays.

Hormones in brief

Hormones are molecules that carry instructions from more than a dozen endocrine glands and tissues to cells all over the body.
Humans have about 50 different known hormones, which vary in their structure, action and response. They control a variety of biological processes including muscle growth, heart rate, menstrual cycles and hunger.

Hormones travel throughout the body, either in the blood stream or in the fluid around cells, looking for target cells. Once hormones find a target cell, they bind with specific protein receptors inside or on the surface of the cell and specifically change the cell’s activities.
The protein receptor reads the hormone’s message and carries out the instructions by either influencing gene expression or altering cellular protein activity. These actions produce a variety of rapid responses and long-term effects.

Estrogen (Oestrogen):

There is no one hormone called estrogen. Estrogen is actually the name of a class of hormones. The three major estrogens produced by women are estriol, estradiol and estrone.

Estrogen is known as a ‘female hormone’ because it plays a key role in shaping the female body and preparing it for uniquely female functions such as pregnancy. Together with progesterone, estrogen regulates the changes that occur with each monthly period and prepares the uterus for pregnancy.

Prior to menopause, the ovaries make more than 90% of the estrogen in a womans body.

Other organs (including the adrenal glands, liver, and kidneys) also make small amounts of estrogen, and this is why women continue to have low levels of estrogen after menopause.
Because fat cells can also make small amounts of estrogen, it is important that women take essential fatty acids when they are going through menopause. Those that do may have fewer problems with hot flushes and osteoporosis (both of which are related to lack of estrogen).


Progesterone is the precursor to estrogen, testosterone, and of all the important steroid hormones.
Progesterone is made from the sterol pregnenolone, which is in turn made from cholesterol, which is made from acetate, a product of the breakdown of sugar and fat in the body.

Progesterone has qualities of both androgens and estrogen. As women approach menopause, less progesterone is produced.

Progesterone deficiency is responsible for many of the symptoms associated with menopause.

Progesterone’s many functions include improving sleep, naturally calming, balancing body fluids, improving fat metabolism, and promoting bone formation.


Androgens are a group of three; Testosterone, DHEA (Dehydroepiandrosterone), Androstenedione.

DHEA: (Dehydroepiandrosterone) The principal androgen in both men and women is DHEA. DHEA is converted into estrogen and androgen-type metabolites (A substance produced in or by biological processes) found only in skin.

Androstenedione: is a metabolite of DHEA and it serves as a direct precursor in the biosynthesis of testosterone.

Testosterone: Women’s ovaries and adrenal glands do produce testosterone.

Every woman will experience a drop in estrogen and testosterone production during menopause. Testosterone is important in strength and integrity of skin, muscle and bone. Women can either make too much testosterone (such as in polycystic ovary syndrome/PCOS); make too little estrogen to mask the testosterone or have a genetic predilection towards highly sensitive skin and hair follicle cells to normal levels of androgens.

Testosterone arises from the circulation and is converted to its more potent, reduced form dihydrotestosterone (DHT), by the enzyme 5a-reductase.

5a Reductase: There are two distinct forms of 5a-reductase, Type 1 and Type 2, which differ in their tissue distributions.

5a Reductase Isoenzyme Type 1: Predominates in sebaceous glands, influencing sebum production. The Type 2 isoenzyme is restricted to certain sites, including the hair follicle, prostate, and other tissues involved in sexual differentiation.

It is Type 1 that is of relevance to the skin treatment therapist when understanding and establishing cause of adult female hormonal acne so this is where our research will eventually go.

The family of androgens are responsible for those masculine qualities; acne, hair loss and hirsutism, (excess facial hair) as well as an increase in both facial and body hair.

DHT: Dihydrotestosterone:

All women produce androgens and these hormones are there for a reason.
It is when androgens outweigh estrogen either through total amounts or genetic hypersensitivity to the mere presence of androgen that a problem may arise.
More efficient conversion of testosterone to dihydrotestosterone (DHT) in the sebaceous gland as a result of locally enhanced Type 1 5a-reductase activity is the more likely to be the cause.

DHT is the major nuclear androgen ultimately responsible for the increased sebum production by the sebaceous gland in hormonal mediated acne

A Conclusion

So there you have it, it all comes down to the enzyme 5a-reductase, and when discussing hormonal mediated acne, this enzyme and how it is produced and what it does is what you have to be thinking about.

There is an enormous amount of research now underway regarding 5a-reductase, and this research is proving that this enzyme has a far reaching effect in many conditions related to hair growth (and loss) as well as sebaceous secretions and potentially excess keratinisation.

Oral contraceptives may worsen acne or stimulate superfluous hair growth

Androgen Inhibitors
For hormonal mediated acne or what many researchers refer to as DHT-mediated acne, a specific anti-androgen that can inhibit 5a-reductase without blocking the androgen receptor is the ideal approach to treating hormonal (DHT)-mediated acne.

It has been found that neither topical acne preparations nor oral antibiotics influence sebum production that has been stimulated by Type 1 5a-reductase.

The androgen inhibitors that are known are the prescription only medications like Androcur and Aldactone, Diane 35 etc; some are used as contraceptive or treatment for superfluous hair.

Many women found that some brands of oral contraceptive improved their acne, while many discovered a worsening of the condition or the stimulation of superfluous hair.

It is the small family of drugs that contain Cyproterone acetate that seems to have a positive effect on hormonal mediated acne because of its anti-androgen profile.
It can be is used for women who have too much androgen production and/or seem to be overly sensitive to androgen activity in their bodies. It is also used to treat acne and/or overactive oil glands and hirsutism as well as androgen dependent hair loss.

As skin care therapists, we can recommend or refer our clients onto a specialist who can then prescribe these androgen inhibitors, but that does not give us a tool that would be effective as a salon treatment.
What we can do is come in at the enzyme level with a topical preparation that inhibits the enzyme 5a-reductase. Already cosmetic formulators have been successful in the research towards such a preparation, and topical therapies that can inhibit 5a-reductase are now available.

Topical therapies that can inhibit 5a Reductase Isoenzyme Type 1:

Azelaic Acid, Vitamin B6 and Zinc

Azelaic acid is a natural non-toxic dicarboxylic fatty acid material made by yeast that grows on the skin called Pityrosporum ovale. (Also known as Malassezia furfur)

It has a demonstrated activity against P acnes, and the ability to decrease micro comedone formation. Keep in mind that Pityrosporum ovale is part of skins micro flora, and therefore part of the eco system of the acid mantle.
Azelaic acid has been found to have a number of qualities that are of benefit to an acneic skin. Azelaic acid is:

  • Antibacterial – it reduces the growth of bacteria in the follicle (Propionibacterium acnes and Staphylococcus epidermidis)
  • Anti keratinising – normalises the disordered growth of the skin cells lining the follicle and on the skin surface.
  • A scavenger of free radicals – i.e. it reduces inflammation.
  • Research has shown Azelaic acid also helps reduce pigmentation.
  • There is strong scientific evidence that Azelaic Acid is a potent inhibitor of 5a- Reductase.

Azelaic acid is also a naturally occurring dicarboxylic acid found in whole grain cereals, rye, and barley and animal products, and has antibacterial plus anti keratinising actions. It is FDA approved as a topical preparation for treatment of acne and is effective against a number of skin conditions when applied topically.

Vitamin B6 and Zinc Sulfate have also shown to inhibit 5-Alpha Reductase individually. When Azelaic acid, Vitamin B6 and Zinc Sulfate where added together at very low concentrations, 90% inhibition of 5 Alpha-Reductase activity was obtained (Published Study).

Azelaic acid is now used as a topical treatment for mild to moderate acne, and may be combined with oral antibiotics or hormonal therapy it is useful for both comedonal and inflammatory acne.

P. Acnes contributes to the inflammatory process, which is aggravated by the wound healing processes you read about earlier in the skin condition related to colour section.

This inflammatory process is generally accompanied by a degree of sensitivity and erythema of the surrounding tissue. These conditions make the skin difficult to treat with some of the product manufactured for acne, as many of the ingredients of these products may induce or sustain the sensitivity and erythema factors.

Because of the high degree of inflammation that comes with an acneic skin, it is always wise to apply a basic majority of permanent diffused redness as opposed to the long-standing (and technically incorrect) classification of a skin type of oily.

Applying the protocols for this skin type ensures that the client treats the skin carefully and uses mild non-abrasive / non-alcohol based cleansers and toners, thus nurturing the flora of the acid mantle.
This philosophy will logically carry over in to any salon treatments you choose for your client in the future, as treating the skin with the permanent diffused redness protocols will encourage healing and slow down the scarring that occurs when skin lesions reside for a long period.
By neutralising the FFAs with EFAs frees up oil flow, and improves the health of the cell membrane with subsequently better active & passive transfer of actives.

In the next instalment we will look at the process of diagnosing the different forms of acne.

For more information about diagnosing this skin condition refer to the book “Advanced Skin Analysis”.

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