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
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