Even after pimples have healed, they may leave dark pink, red, brown or purplish spots, called post-inflammatory hyperpigmentation, or PIH. It is the skin's reaction to an inflammatory injury (like inflamed pimples).
PIH will fade over time. But because it can make you feel self-conscious about your skin, you may choose to treat it.
Before You Begin Treatment:
- Your acne should be under control, or at least being treated. Otherwise, each new pimple could cause another PIH macule, reducing the effectiveness of treatment.
- Use a broad-spectrum sunscreen daily. The sun may darken the discolorations and increase fading time.
- Monitor your skin for irritation. Although they are helping you clear your skin, acne treatments also have the potential for causing irritation. Unfortunately, irritated skin could lead to PIH. If PIH is a problem for you, let your dermatologist know if your skin becomes irritated from your acne treatments.
- Whatever treatment option you choose, understand that improvement will take time. Think in terms of months rather than weeks.
When you're ready to begin treatment, you have plenty of options. Remember, this isn't a comprehensive list. Other treatments may be available. Your dermatologist can help guide you to the right treatment for your skin.
Alpha Hydroxy AcidsAlpha hydroxy acids, especially glycolic acid, are a good starting point for PIH treatment. Alpha hydroxy acids (AHAs) help speed up the skin's natural exfoliation process, which can help improve the appearance of PIH.
Many over-the-counter cleansers, lotions, creams, and gels contain AHAs. These may be a good choice if hyperpigmentation is fairly mild. Stronger AHA treatments are available with a prescription.
AHAs are often used as anti-aging treatments too, and will leave your skin super soft and smooth.
Topical RetinoidsTopical retinoids are often prescribed to acne patients. Retinoids help clear acne by speeding up cell turnover rates. This rapid exfoliation can also help fade PIH.
Retinoid creams include Retin-A (tretinoin), Tazorac (tazarotene), and Differin (adapalene). The fact that they lessen post inflammatory hyperpigmentation as they treat acne breakouts is an added benefit for many people. These medications are available with a prescription only.
HydroquinoneHydroquinone is a widely used treatment for hyperpigmentation. It is available over-the-counter at 1% to 2% strength, and in 3% to 4% prescription creams. Hydroquinone works by blocking the enzyme responsible for melanin production, which helps lighten the skin.
Hydroquinone creams often contain additional lightening ingredients, such as kojic acid, glycolic acid, tretinoin and other retinoids, or vitamin C. These combination creams can give you better results than using hydroquinone alone.
Hydroquinone creams should be carefully applied to darkened areas only to prevent the unwanted lightening of your natural skin color. Hydroquinone may cause irritation in sensitive individuals. It's worth talking to your doctor before beginning hydroquinone treatment.
N-Acetyl Glucosamine and NiacinamideThere is some evidence that N-acetyl glucosamine (NAG) and niacinamide may reduce hyperpigmentation. However, more studies must be completed to verify these findings.
It's thought that NAG and niacinamide interfere with melanin production. These ingredients can be found in over-the-counter cleansers and moisturizers.
They'll probably work best for those with mild pigmentation problems. If your hyperpigmentation is moderate to more serious, you'll get better results with a different treatment.
Azelaic AcidAzelaic acid is another medication used to treat acne as well as PIH. It works by decreasing inflammation and speeding up cell turnover rates. Azelaic acid is sometimes used in conjunction with glycolic acid or tretinoin.
Some studies have shown azelaic acid to be as effective as hydroquinone at treating hyperpigmentation. It is a good alternative for those who may be unable to use hydroquinone.
To get azelaic acid, you'll need a prescription from your doctor.
Procedural TreatmentsPIH can also be treated professionally at skin spas, medi-spas, or your dermatologist's office. Procedural treatments include various chemical peels and microdermabrasion.
But just one treatment isn't enough to fade PIH. Most likely you'll need a series of treatments spaced a week or so apart (depending on the procedure you're having done). Your doctor can help determine which of these treatments, if any, would be most effective for you.
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