Adding Insult to Injury: Post Inflammatory Hyperpigmentation
Note: Nothing in this post is intended as medical advice! It’s for information only; some of the things mentioned below are inappropriate for people with certain medical conditions, so discuss with your doctor.
I’ve sort of mentioned this in a couple other posts but not discussed it in detail yet – for the past several years (maybe 5 or 6?) I’ve been struggling with a moderate to severe case of adult acne. I sailed through high school with no more than three or four pimples at once, though of course at the time I thought my skin was so terrible. When I was in my early 20’s, I switched to single hormone birth control because dual hormone methods gave me migraines. Shortly after that my skin started breaking out, and it was worse than it had ever been before – we’re talking deep cysts, plus pimples that covered most of my chin and cheeks. Real cute, hormones.
I eventually gave up on spending all my money on various potions and saw a dermatologist. Side note – if you have acne and access to healthcare, do not pass go, just see your doc. It’ll save you time and probably money. After a couple years, several medications and another change in BC method, I finally started to see some improvement in my skin earlier this year; it’s still not cleared up (I’m going to start a course of Accutane next month), but it’s at least… not painful.
But here comes the “insult to injury” part. I have type III skin, which means I’m medium-toned, tan easily and don’t sunburn often or badly. Unfortunately it also means I’m prone to post inflammatory hyperpigmentation, which are the dark spots left behind even after the acne has gone away. Easy tanning goes for the dark spots too, so they tend to be darker and last longer than they would for very fair-skinned folks. I’ve still got a ways to go before my skin is completely cleared up, but once it is, I’ll be on a mission to fade the scars. I conveniently have access to university computers, so I’ve done some research. I originally wrote this post for a skincare forum that I’m a member of, but I thought it might be good to share it here too.
What does this have to do with makeup? Well, I don’t know about everyone else, but covering up discoloration is the most time-consuming chunk of my daily makeup routine. Primer to keep my oily skin from breaking down my foundation, foundation to even out my skin tone, and concealer (both green-tinted and regular) to hide the darkest spots. That’s a solid 8-10 minutes I could be using to perfect my winged eyeliner, which I’m still pretty terrible at, or inventing exciting new eyeshadow color combinations. Basically, I want to be able to spend more time on the fun stuff!
First, some terminology
This post will focus on post inflammatory hyperpigmentation, which are the dark marks that remain after an acne lesion has healed. It’s commonly referred to as “acne scarring” but it isn’t a true scar, since it’s often transient and doesn’t involve changes to the collagen in the skin. Even though this post won’t go into other types of acne scarring, I’ll leave some descriptions here for the sake of knowledge.
Hypertrophic scarring – raised lumps of scar tissue where an acne lesion was. Sometimes there is an overgrowth of scar tissue that extends beyond the original inflammation site (keloid scarring). This type of scarring is common on the torso.
Atrophic scarring – depressions in the skin due to a loss of collagen. Depending on the shape and area covered, these are classified into rolling, box or icepick scars.
What is PIH, and what causes it?
Post-inflammatory hyper pigmentation (PIH) results from an overproduction of melanin following inflammation of the skin. Cytokines (which modulate immune response) and inflammatory mediators can have a stimulatory effect on melanocytes (cells that produce melanin), which results in increased melanin production. Inflammation can also cause the destruction of basal keratinocytes (skin cells), resulting in an accumulation of pigment at the injury site. It can occur after any type of injury to the skin, including acne, dermatitis or traumatic injury, and can exist at the dermal and/or epidermal layers. While it isn’t physically harmful, many people seek treatment due to the social and emotional effects.
What are the risk factors?
PIH can occur in anyone. However, it’s usually more common, noticeable and persistent in people with darker skin types (Fitzpatrick types III-VI). The color of the hyperpigmentation can vary depending on skin tone and location in the skin (dermal vs epidermal), showing up as red, purple, brown or bluish. There’s also a correlation between the intensity of the original inflammation and the intensity of the resulting PIH. Repeated inflammation at the same site (such as reoccurring acne cysts) can exacerbate the effect.
Well, how do I avoid it?
PIH is notorious for taking a long time to treat, so as they say, an ounce of prevention is worth a pound of cure. Avoiding inflammation altogether is the best way to avoid PIH, but the second best is to be prompt about treating any skin conditions that might cause it. Also avoid doing anything that causes inflammation to become worse (so don’t pop your pimples, mmkay?).
I already have it! How do I make it go away?
Fortunately there are lots of well-studied treatments for PIH. Below are some of the most-researched topical treatments.
Sunscreen – Nearly all of these treatment options increase the skin’s sensitivity to the sun, so a high-SPF/PPD broad-spectrum sunscreen must be used along with them. Otherwise, there’s a good chance that not only will the treatment for PIH fail, but they’ll actually cause additional photo damage to the skin. Used on its own, sunscreen can help prevent any existing hyperpigmentation from becoming worse.
Hydroquinone – Hydroquinone works by suppressing the melanocyte metabolic processes, causing a gradual decrease of melanin pigment production. While it can be very effective at depigmenting, many of the formulations existed before the formation of the FDA, so they haven’t been tested for safety or effectiveness. Some studies have shown that oral hydroquinone causes cancer in rodents, and others suggest that it may be toxic to melanocytes in humans. Additionally, there is a risk of ‘halo’, or the unwanted lightening of skin around the hyperpigmented area, which is more obvious in darker skin tones. Even though some hydroquinone products are available in OTC formulas, it’s best to use it under the supervision of a doctor.
Retinoids – These vitamin A derivatives are commonly prescribed for acne but can also assist in fading hyperpigmentation. They work by increasing epidermal turnover, facilitating melanin dispersion and removal. Adapalene (Differin), tretinoin (Retin-A) and tazarotene (Tazorac) have all been shown to be effective in clinical studies. The most common adverse effects of retinoid use are redness, dryness and irritation. Retinoid dermatitis can lead to additional hyperpigmentation, especially in darker skin, so it can be beneficial to start with a lower-strength retinoid and gradually increase the amount and frequency of use. Retinoids can be prescribed by your doctor.
Chemical Peels – Superficial chemical peels with alpha hydroxy acids are common treatments for PIH since they are generally well-tolerated. Chemical peels work by promoting exfoliation and dispersing basal layer melanin. Glycolic, lactic, and salicylic acid peels have all been shown to be effective in treating hyperpigmentation. Glycolic acid may also be effective in treating superficial atrophic scars because it increases dermal collagen synthesis. Depending on the active used, the concentration of the active and how long the peel is left on the skin, the ‘depth’ of the peel can be controlled. Potential side effects include a burning sensation, redness, and skin irritation/sensitivity. Salicylic acid can potentially cause dryness, especially for people with drier skin types. Excessive irritation can lead to additional hyperpigmentation, so it’s important to choose the ingredients and strength of the peel carefully, taking your skin type and any allergies/sensitivities into account. Patch testing is also extremely important in order to minimize any adverse effects. Peels can be performed by your dermatologist, and kits are also available for use at home.
Vitamin C– The antioxidant properties can help suppress melanin synthesis. Other benefits include anti-inflammatory effects and possible photoprotective properties. L-ascorbic acid, the most potent form, isn’t very stable in solution, so vitamin C products should be chosen and stored carefully. It is most effective when combined with other treatments. Vitamin C is available in many OTC products.
Daily AHAs – In addition to use as peeling agents, alpha hydroxy acids can be used as frequently as every day in lower concentrations to promote regular and even exfoliation of the skin. Over time, this can assist in fading hyperpigmentation. Many skin types can tolerate regular AHA use along with other PIH treatments. Many AHA products are available over the counter.
Azelaic Acid – This is a dicarboxylic acid that was developed for the treatment of acne and rosacea. In addition to fighting acne by killing bacteria and decreasing keratin production, it can help fade hyperpigmentation through tyrosinase inhibition and cytotoxic effects toward abnormal melanocytes. It is generally well-tolerated, but may cause redness, burning, irritation or allergic reaction. Azelaic acid (commonly sold under the brand name Finacea) can be prescribed by your doctor.
Niacinamide – a form of vitamin B3. It works by inhibiting melanosome transfer from melanocytes to keratinocytes. Clinical studies seem to be using a concentration of at least 4%. In general, it does not cause irritation and is well-tolerated.
There are some other ingredients that may be effective for reducing hyperpigmentation, like kojic acid, arbutin and licorice root extract, but they haven’t been well-studied for effectiveness.
How long will it take to go away?
The healing process is somewhat unique for each person, so the amount of time needed for treatment can vary widely depending on your skin, the severity of the PIH, the treatments you choose, and your consistency in applying the treatment. In some cases, it may exist long-term or permanently. For many people, especially those with darker skin, a minimum of 3-6 months of treatment is necessary before significant improvements are visible, and it could take a year to several years before the condition is completely resolved.
That was a bit of a novel, but hopefully helpful to someone out there. I’ve started incorporating some of these into my skincare routine, and so far so good. I’ve been using retinoids (Retin-A Micro and then Tazorac .05%) for about 9 months. There definitely was an adjustment period (maybe I’ll do a post about that sometime in the future? Shout out in the comments if you’d like to see that), but it seems to be fading some of the darker areas and it’s really helped with the expression lines on my forehead. I also love Elta MD UV Clear SPF 46 sunscreen (reviewed here), which has 5% niacinamide in it. I tried and liked the 40% lactic acid peel from Makeup Artist’s Choice, but I stopped using it when my skin freaked out about the weather change.
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