Who is at Risk of Developing Pimples?

Acne Risk Factors: What are they?

Some individuals are more acne prone than others. Is it just heredity or are there some other factors responsible for the pimple eruptions?

Though there is a hereditary tendency for acne eruptions, there are many factors that might contribute to the development of acne in normal individuals.

Who is at Risk of Developing Pimples?

 Common acne risk factors include age, sex, occupation, hormonal imbalance, food habits, medications, outdoor activities and stress.

Acne and Food: Choice is yours!
                                   Acne and Food: Choice is yours!


Age and Acne

 Adolescence is of course the most common age for acne. The onset of puberty brings in hormonal changes which affects the sebaceous gland activity and other factors stimulating the acne development.

Acne and Gender

Though both sexes are equally affected, acne is more severe in males. Risk of acne complications like acne scars are consequently more in the males.

Hormone Disturbances Causing Acne

 Androgenic hormones from the testes, ovaries and the adrenal cortex are mainly responsible for the sebaceous hyperactivity in acne. Hence any diseases of these organs, medications stimulating or increasing the secretions of these hormones or drugs having similar pharmacological effects can stimulate acne production in some individuals. It is common for women to get acne eruptions, usually of mild to moderate type, just before or during their menstrual periods. In pregnancy, some women experience worsening of their acne, while, in others, acne simply disappear during pregnancy.

Many patients with polycystic ovarian disease have moderate to severe type of acne along with unwanted hair growth. Low dose oral contraceptives are beneficial in treating acne in some female patients who show high levels of testosterone or Dehydroepiandrosterone (DHEA). Some combination pills which contain androgens could induce acne eruptions as well.

Virilization disorders where the male hormone levels are increased in females due to adrenal or ovarian growths are characterized by acne eruptions, abnormal hair growth (hirsuitism), voice changes, clitoral enlargement and increased libido.

Topical Applications Causing Acne

Topical Applications causing Acne
Topical Applications causing Acne

 Acne is caused by the occlusion of the hair pores with plugs caused by thickened walls and action of the bacteria P.acnes on the oily sebum. It follows that anything irritating or further occluding the skin surface is bound to induce or aggravate acne. Oily cosmetic products like cold creams, moisturizers or oil based foundations can cause fresh acne eruptions and hence should be avoided by teens with acne prone skin.

Oil, gel or pomade applications on face could cause acne bumps to appear on the forehead, scalp or behind the neck.

Topical steroids, especially the potent fluorinated classes of topical steroids are infamous for causing acneiform eruptions even in individuals without a previous history of acne.

Occluding and Irritating Agents as Acne Risk Factors

In addition to the occluding oily creams and oils, occluding synthetic dresses(body acne), helmets (forehead, scalp and neck acne), industrial oils(chloracne on hands and forearms), shoulder pads in players also induce acne eruptions. To be qualified as acne, the individual should have the tell tale comedones in nearby skin or face. Otherwise these should be called folliculitis, the inflammation of hair follicles. Most of the acneiform eruptions that are supposedly caused by chronic rubbing are not acne lesions, but folliculitis.

Acne Inducing Medications

 Certain medications can induce acne like eruptions or exacerbate existing acne. The most common culprits are systemic and topical steroids, phenytoin, isoniazid, lithium, iodides and bromides.

In addition to the above, acne eruptions are worse in hot and humid conditions where sweating and increased sebum secretion can enhance the follicular occlusion and P.acnes proliferation. Acne has


also been found to be increased under stressful conditions, probably through the hormonal stimulation of the sebaceous glands.

Published by Dr Hanish Babu, MD on 24th May, 2018

The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or the website will not be responsible for any consequences. The images provided are for illustration purpose only and are copyrighted.

Copyright 2018 © Dr Hanish Babu, MD

Acne Triggers

What Causes Pimples to Appear or Worsen?

Though acne is one of the commonest diseases affecting the humanity, the triggering factors of acne have not yet been delineated conclusively.

Acne vulgaris is a common, chronic skin disease affecting almost everyone at least once in their life time.

In most people, acne appears during adolescence, though it could appear de novo at any age. In 2000, Layton AM, in an article in the Medicine titled ‘Acne vulgaris and similar eruptions’, noted that approximately 5% of women and 1% of men 25–40 years of age either continue to get acne lesions or develop acne (late-onset acne) after adolescence.

It will be interesting to analyze what triggers acne and whether the life style is also a deciding factor, in addition to the hereditary and hormonal causes.

Acne Triggering Factors: Age & Hormones

Acne is most prevalent among adolescents and young adults, affecting approximately 85% of people at some point between 11–30 years of age. Peak incidence is seen in females 14–17 years of age and males 16–19 years of age.

During puberty, androgen hormone production increases which induces an increase in the production of sebum and the development of greasy skin. This stimulates a cascade of events that cause acne formation.

In females, hormonal imbalance due to ovarian diseases (for example in polycystic ovarian disease) induces acne eruptions. There is a flare up of acne immediately before the menstrual periods in some women. Pregnancy, in some, clears acne; while in others, there is a worsening of acne during the expecting months.

Acne Trigger: Heredity

A hereditary predisposition for acne formation has been noted by most studies. It is well known that tendency to pimples and acne scar formations runs in families. These could be due to the inborn sensitivity of the sebaceous glands to hormonal actions during puberty.

Acne Triggers: Occlusive Cosmetics

In individuals with an acne prone skin, use of oil based greasy foundations and face creams may stimulate new acne eruptions by causing build up of sebum within by blocking the hair follicle pores. This is known as acne cosmetica. Such individuals are advised to use only water based, oil free cosmetics as make up.

Acne Trigger: Aggressive Washing

Acne is not caused by poor hygiene and aggressive and frequent washing with abrasive soaps can worsen the acne situation in most sufferers.

Acne Triggers: Topical and Systemic Steroids

Potent Steroids cause acne
Potent Steroids cause acne

Steroids, particularly the medium and potent strength topical halogenated steroids, can induce eruption of steroid acne, where sudden appearance of skin colored and pus filled bumps worsen the acne after an initial period of improvement for a few days. The initial period of improvement with steroids is because of their anti-inflammatory actions.

Prolonged periods of oral steroids can trigger pimples on the face and body in a majority of patients.

Acne Triggers: Medications

Many systemic drugs and topical applications may induce fresh acne eruptions, known as acne medicamentosa. In addition to the steroids, drugs like phenytoin, lithium, iodides and the anti-tuberculous medication INH are known to trigger acne. Topical agents like chlorinated hydrocarbons, coal tar derivatives, cutting oils and grease cause acne like eruptions even on body areas where normal zits usually do not appear.

Acne Triggers: Diet

Food as a cause of acne is still a controversial topic among dermatologists, despite patient’s anecdotal reports and a few studies which blame westernized dietary habits, milk and milk products, and food items containing high levels of iodine and, possibly hormones. More studies and research is required in this field, but it would suffice to state that if the patient notices exacerbation of existing pimples or new acne eruptions after certain foods, these should be eliminated from the diet.

Acne Trigger: Stress

Hormones and other neuro-endocrine mechanisms during stressful periods can trigger fresh acne eruptions. Recently many studies have proven beyond doubt that the acne condition worsens in teens during stressful periods like exams.

Acne Trigger: Sunlight?

Limited sunlight exposure has a positive effect on acne, though remaining longer duration in hot, humid daylight actually has been found to worsen acne. Those who are using retinoids and tetracycline to treat acne should avoid sun exposure, as this can cause photosensitive reactions on the skin.

Acne Trigger: Hair Products

An overlooked cause of acne eruptions, especially on the forehead is use of oils and greasy creams on the hair.

The above list is not all inclusive by any means. There would be many more unknown triggers for acne, as many individuals, even in adulthood, get sudden acne eruptions without any identifiable causes. There is certainly a need for more research in this field.

Published by Dr Hanish Babu, MD on 24th May, 2018

The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or the website will not be responsible for any consequences. The images provided are for illustration purpose only and are copyrighted.

Copyright 2018 © Dr Hanish Babu, MD

Pathogenesis of Acne or How Does Acne Develop?

How Acne Occurs
How Does Acne Occur?

The pathogenesis of acne or how acne forms  includes a combination of factors affecting the integrity of the hair follicle and its oil producing gland, the sebaceous gland.

The study of how acne develops is a fascinating one. There are many points to be clarified regarding the pathogenesis of acne. What is the basic cause of acne? Why does it appear only on some parts of the body? Why does acne have a course with waxing and waning? What is the role of hormones, skin oiliness and germs in the development of acne?

There are four major causes contributing to acne development –

  1. Increased sebum production
  2. Colonization of the hair follicle duct with the germ Propionibacterium acnes
  3. Thickening and plugging of the hair follicle walls and opening, resulting in comedo formation
  4. Inflammation of the pilosebaceous unit. Pilosebaceous unit includes the hair follicle and its associated sebaceous gland.
How Acne Develops
Stages of Acne Development

How Acne Develops: Increased Sebum Production or Seborrhea

Sebum is the oily secretion from the sebaceous gland lying alongside the hair follicle. Sebum is responsible for maintaining the oiliness of the skin and the hair. It keeps the skin supple and smooth. In infancy and childhood, the sebaceous glands are small and inactive. The sebaceous glands enlarge and become active during puberty under the influence of the androgen hormones secreted by the adrenal and gonadal glands.

The increased production of sebum, seborrhea, may be genetically programmed; some individuals are more acne prone than others. It is also seen that sebum secretion and sensitivity of the sebaceous glands to the action of androgens vary from follicle to follicle and area to area. This is the reason why acne severity varies between different follicles and hair bearing areas of the body.

How Acne Develops: Bacteria Colonization

 The increased sebum secretion predisposes to the overgrowth of the bacteria Propionibacterium acnes within the hair follicle and the sebaceous gland. The action of these bacteria on the sebum is thought to produce irritant products like free fatty acids within the hair follicle. These and other chemical mediators known as cytokines are thought to be responsible for the thickening of the hair follicle, plug formation and inflammatory events in acne.

How Acne Develops: Comedogenesis or Comedo Formation

 The thickening of the hair follicle walls, known as ductal hypercornification, and the keratinous plug formation is the cause for the formation of the comedo, better known as the acne whiteheads and blackheads. Comedo formation is the first stage of development of acne. When the follicular opening is closed with the keratinous plug, it is known as closed comedone or whitehead, and when it is dilated, the open comedone or blackhead. The black color seen in the blackhead is not dirt, but due to the sebum changing color when it comes in contact with the atmospheric oxygen.

How Acne Develops: Inflammation

 Inflammation of the hair follicle and the sebaceous glands and the surrounding dermis is the final event in the moderate to severe types of acne. Inflammation results in red, painful and pus filled bumps in acne. Acne gets inflamed by a combined action of P.acnes, the bye products of the action of the bacteria on the sebum, the corneocytes lining the hair follicle duct and the inflammatory mediators induced by the sebaceous glands.  

The inflammation weakens the follicular and sebaceous gland walls which rupture to discharge the sebum and part of the comedone into the dermis. This induces a severe foreign body inflammatory reaction resulting in formation of acne cysts and nodules.

Recent Advances in Acne Pathogenesis Information

 The 2009 acne update from the Global Alliance to Improve Outcomes in Acne throws some interesting insights to the pathogenesis of acne:

The inflammatory events in acne precede the hyperkeratinization (thickening of the follicular walls).

  1. acnes specifically activate special receptors on the cell membranes of inflammatory cells.

The sebaceous gland is a neuroendocrine-inflammatory organ that coordinates and executes a local response to a variety of neuro-endocrinological and stress induced stimuli.

Sebaceous gland plays an important role in hormonally induced aging of skin.

In addition to their action on sebaceous gland activity, androgens have influence on the follicular cells (corneocytes) also.

Oxidized lipids in sebum (possibly altered by P.acnes) induce the production of inflammatory mediators.

Sebum contains several matrix metalloproteinases (MMPs) which play important roles in the inflammatory process of acne. The levels of MMPs are significantly reduced in the acne lesions following treatment.

The acne information provided above is a short review of how acne develops. The degree of plugging of the comedones and the extent of inflammation decides the severity of the pimples. Different types of acne are categorized according to the severity of the acne lesions.


  1. Simpson NB & Cunliffe WJ. Disorders of the Sebaceous Glands in Rook’s Textbook of Dermatology. 2004; 7: 43.1-43.75.
  2. Diane T, Gollnick H et al. New insights into the management of acne: An update from the Global Alliance to Improve Outcomes in Acne Group. J Am Acad Dermatol, 2009;60:S1-50.

    Published by Dr Hanish Babu, MD on 24th May, 2018

    The information given in this article is for educational purpose only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, the author or the website will not be responsible for any consequences. The images provided are for illustration purpose only and are copyrighted.

    Copyright 2018 © Dr Hanish Babu, MD