From salicylic acid to retinol, there's a handful of effective skincare ingredients with proven spot-zapping credentials out there. But right now, everyone's googling one in particular: benzoyl peroxide.
If you experienced acne in your teens, you might already know benzoyl peroxide as that ingredient with a bad rap. Typically available on prescription, it is known to be quite harsh on sensitive skin, causing dryness and bleaching clothes and pillowcases. But it can be transformative, especially for those with skin prone to excessive oiliness and breakouts.
Ahead, we asked Dr Kemi Fabusiwa, medical doctor and director of Joyful Skin to uncover everything you need to know about benzoyl peroxide and how best to slot it into your daily skincare routine.
What is benzoyl peroxide?
"Benzoyl peroxide is a chemical compound with powerful antimicrobial properties," says Dr Fabusiwa, which essentially means it kills bacteria living on the surface of the skin. "This decrease in the number of bacteria helps to reduce the bacteria-induced inflammation that can lead to the development of acne," adds Dr Fabusiwa.
In skincare, benzoyl peroxide usually comes in gel or cream treatment form, but it's also available as a facial cleanser.
What does benzoyl peroxide do for skin?
"Benzoyl peroxide is a safe, cost-effective acne ingredient used by dermatologists," says Dr Fabusiwa, who rates it slightly higher than antibiotics where certain types of acne are concerned. "While topical antibiotics also kill bacteria on the skin, you can quickly become resistant to them, which eventually renders them ineffective," continues Dr Fabusiwa. "However, with benzoyl peroxide, this resistance does not occur."
Dr Fabusiwa also pinpoints benzoyl peroxide's exfoliating properties, which help unclog pores to fight spots.
How do you use benzoyl peroxide?
Think of benzoyl peroxide products like treatment, rather than a moisturiser. "Benzoyl peroxide creams or gels are best used after cleansing (and toning, if you use a toner) but before your moisturiser at nighttime," says Dr Fabusiwa. It is advised to use the product once a day. "Make sure you allow enough time between applying your benzoyl peroxide and your moisturiser, though, so that it can absorb nicely into the skin without piling (rolling off the skin). This also increases its maximum efficacy."
Experts recommend avoiding sunlight when using benzoyl peroxide as it can make the skin sensitive, so it is advised to wear a high factor SPF during the daytime.
How long does it take benzoyl peroxide to work?
According to the NHS, it can take up to four weeks to notice a difference when first using benzoyl peroxide for acne. Like all skincare, the key is consistency, but if your skin becomes very irritated or painful, it's best to consult your GP or a skin specialist immediately.
What are the side effects of benzoyl peroxide?
"Benzoyl peroxide has drying properties, which means that it can be irritating to those with sensitive skin," says Dr Fabusiwa. You're likely to notice dryness and flaking, but this is normal. "For those prone to irritation, it’s best to use lower strengths of this ingredient and to ensure the skin is well moisturised in the morning," adds Dr Fabusiwa. "The peroxide element may also lead to an unwanted bleaching effect. To combat this, try and apply the benzoyl peroxide specifically to the problem areas and avoid getting it elsewhere." Dr Fabusiwa adds that as benzoyl peroxide is anti-inflammatory by nature, it improves skin for all, and is suitable for all skin tones.
What are the best benzoyl peroxide skincare products?
Acnecide is a 5% benzoyl peroxide spot treatment for acne on the face, and can be bought over the counter at many pharmacies. Other benzoyl peroxide products include Epiduo, a gel which combines benzoyl peroxide and adapalene (a type of retinoid) to minimise acne, but it is only available via prescription. Certain online chemists sell Epiduo but an online consultation is required. Duac Once Daily Gel is another benzoyl peroxide treatment (combined with 1% topical antibiotic) available on prescription from UK pharmacies in varying strengths, such as 3% and 5%, depending on the severity of your acne.
For more advice on benzoyl peroxide, visit a qualified skin specialist or book an appointment with your GP.
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