Propionibacterium Acnes: Acne Bacteria

acne bacteria

Propionibacterium Acnes: Acne Bacteria

While reading Sahar’s article on acne, I got very curious about this whole acne thing. Although in my skin article I had concluded that most acne flare-ups happen because of hormonal changes, I had not touched upon the mechanics of the thing. And it’s good to know what’s happening because then you know how to deal with it. If you look at it objectively, there are two parts of this acne phenomenon- the first is the prevention of acne and the second is the removal of acne and acne scars. For now, I’m going to deal with the former.

As I said in my skin article, acne is produced by excess secretion of sebum (which can be triggered by hormonal changes, stress, or some food triggers (such as chocolates or oily food) which clogs the pores or the hair follicles. Once your pores are clogged, your acne can take two shapes- comedonal (blackheads or whiteheads) or inflammatory (pimples). The latter one is the one giving most of the trouble because most of us are tempted to scratch it or pop it, leading to scars on our face.

So why does your acne becomes inflammatory? The answer is Propionibacterium Acnes, the skin bacteria. No, acne is not contagious. This bacteria is largely commensal and part of the skin flora present on most healthy adult human skin. Propionibacterium Acnes feeds on the fatty acids in the sebaceous glands on sebum secreted by follicles. When a pore is blocked, this anaerobic bacterium overgrows and secretes chemicals that break down the wall of the pore and cause inflammation.

Remember that the presence of these bacteria is not bad. It is anyhow present on healthy skin. It is when it starts feeding on the excess sebum and secreting toxic chemicals is when you have a cause to worry.

The Cure?

Well, Benzoyl Peroxide comes to my mind. It not only kills the bacteria but also dissolves the impurities clogging the pores. You can find Benzoyl peroxide in many over-the-counter acne medications such as Clearasil and ProActiv. Benzoyl peroxide works by introducing oxygen into the pore, thereby killing P. acnes. When the bacteria population is reduced, the number of breakouts on the skin is reduced as well. It also helps rid the follicle of excess dead skin cells. Clearing the pore of cellular debris will lessen the chance of pore blockages, or comedones. So, benzoyl peroxide helps prevent breakouts before they start.

Even after acne clears up, you’ll probably still have to use your treatments. If you don’t, bacterium populations can increase and acne may return.


Start with medications which have a small concentration of Benzoyl peroxide (2- 4%) to acclimatize your skin and then move on to a little higher concentration if needed. Apply over all the areas affected by acne. Use once or twice daily.

What is the Difference between Benzoyl Peroxide and other treatments of acne such as Salicylic acid and retinoids?
Simply this- Benzoyl peroxide is able to kill Propionibacterium Acnes where as Salicylic acid and Retinoids can only clean up the dead cells and open clogged pores. Hence, Benzoyl peroxide is used for inflammatory acne (pimples) whereas Salicylic acid and Retinoids are used for comedonal acne (blackheads and whiteheads). Savvy? 🙂

Do I have a last word?
Yep, do not pop your zits; the pressure applied while popping your zits pushes the bacteria and toxic chemicals further inside pores causing further inflammation. And you’d have to deal with acne scars also.

Rosacnil Gel for Acne and Skin Blemishes
Acne: Types, Causes and Cure


41 thoughts on “Propionibacterium Acnes: Acne Bacteria

    1. Hi Monika,

      What you actually ‘pop’ in a zit is the ‘pus’ that is our skin’s defense mechanism to inflammation and toxic substances. In blackheads or whiteheads, there are only excess sebum and dead skill cells. Nothing to pop. Just clean it with some salicylic medication. 🙂

      1. thanks for the info Sanjeev. since i actually squeeze my ‘whiteheads’ out (become an addiction now..grossse!!!!! sorry), i think the solution is to apply salicylic medication as mentioned above. Will you or anyone on the list know where I can buy this?

      2. how is pus a defence mechanism?
        i see that evn a puss full of acne does leave scars..and infact also spreads the bacteria around even when it busts naturally and then emerges a new pimple in the vicinity :waaa: :waaa: :waaa: :waaa: :waaa: :waaa:

        1. pus formation is absolutely a defense mechanism– our body cells fight with the bacteria causing acne ,which results in the release of many this total combo of dead bacteria,body cells,chemicals etc etc etc forms the pus. it cant spread the bacteria in that way. the new sprout you see, is just another bacteria being killed by your body cells :))

  1. i got so much knowledge abt acne. i have a problem of acne from last weeks i have a oily skin bt nowadays it become dry i have a fear that if my face become dry and pimplewala :chewnails

      1. Sanjeevji…..I am still young :scream: :scream: :scream: :scream: :scream: :scream: :scream: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali:

          1. tab toh teek hai :smug: :smug: :smug: :smug: :smug: :smug: :smug: I was ordering some concentrated sulphuric acid online… :pissedoff: :pissedoff: :pissedoff: :pissedoff: :pissedoff: :pissedoff: good thing you clarified O:)

              1. I don’t have any wrinklessssssss :hunterwali: :hunterwali: :hunterwali: :hunterwali: :hunterwali: :scream: :scream: :scream: :scream: :scream: :scream: :scream: I was going to pour it over your head :phoolan: :phoolan: :phoolan: :phoolan: :phoolan:

  2. Great write up…. :waytogo:
    I think i am going to search for products with Salicylic acid and Retinoids… :yes: :yes:
    I dont have inflammatory pimples…
    Thank u Sanjeev :yahoo: :yahoo:

  3. I never knew Benzoyl Peroxide was actually better than salicylic aci and Retinoids . But benzoyl peroxide is very very drying for me 😥 😥
    I am currently using Clindamycin phophate it takes sometime to work but it does work well :))

          1. benzoyl peroxide is definitely drying Ritika… don’t just slother up ointments on your face.
            its a drug and so a proper regimen and proper dosage has to be followed.
            just use droplets(but in adequate dose) over the affected region. dont wash off immedietly.let it dry by itself.and use the moisturiser ( a mild one if you have oily skin in the rest of your face)..wash with plain lukewarm water /mild foaming cleanser. you have to use the ointment twice daily (at a gap of 12hours and preferably when you stay indoors)
            no rubbing hard/scrubbing.
            and all drugs do have some or other side effects..benzoyl peroxide may cause irritation ,redness etc..stop using it for some days and consult a dermat asap. O:)

  4. very informative n to the pt article! I hv a super oily skin n used 2 suffer frm al types of acne posible :waaa: but thnks 2 proactiv which nt only ended my acne pblw but nw my scars r also very much cleared! :waytogo:

  5. hai..
    This site has been very info.. i have combo skin & suffer from ol type of acne and ma face is full of acne scars… :scream: :pissedoff: nothing seems to work..plzz suggest sumthing frndzzz …is proactive gud..vere do get it from…???

    1. for severe acne/acne vulgaris, benzoyl peroxide is a good drug.but in case of scars medical treatment depends upon the type of scar you have (clinically we describe the scars to be of 4 types-ice picks,box type,hypertrophic or rolling an the treatment differs in each case. but most common practices are- laser therapy,microdermabrasion,chemical peels,cryosurgery etc (to be done strictly under medical supervision.and they often require use of local anaesthetic agents)

    2. hi gayathri ,actualy individual skin react differently wth products. But u can give proactiv a shot,n u hv 2 use it religiusly n patiently! It is little bit dryin initialy but i used there green tea moisturiser after that n everythng setteld!
      N yes they gv a free gft wth dere kit cald refining mask which i use once a week! I hv been using these since 1 yr n my skin has improvd a lot! U can order it online on (they also hv cash on delievery). I hope it helps! :waytogo:

  6. :thanks: for this great article,Sanjeev ji! I’ll show it to my brother who suffers a lot because of his (painful) pimples. :shy: And then I’ll kick him and make him visit a dermatologist. :whistle:

  7. :yes: :yes: :yes: nyysshhh Sanjeevji.. :snicker: :snicker: made me remember my micro classes n dermat opd’s he he he :shying: :shying:

  8. I used to have so many pimples in my teens… I used to be super scared 🙁 I keep getting an occasional pimple now but I always keep a small tube of bennzoyl peroxide with me… in between that and a white toothpaste I get all better 🙂

  9. Great post! :thumbsup: I never knew the nitty-gritty on the process of pimple formation per se. I’ll keep this information in mind now. It’ s always good to know more about the enemy. 😛 😛

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