Topical acne treatment
has been a well known treatment for quite some time, and benzoyl peroxide
is arguably the most widely used drug formations available. Benzoyl peroxide
exhibits strong antimicrobial action, slight anti-inflammatory effects, and
anticomedogenic attributes, making it a very effective first-choice medication
for acne. Responses to treatment may be obtained within five days of initial
use.
Treatment with Benzoyl Peroxide Alone
Treatment with benzoyl peroxide alone significantly improves inflammatory
acne, with side effects limited to common irritant dermatitis with erythema,
scaling, and itching. These side effects can be controlled by administering
benzoyl peroxide less frequently or in smaller amounts. The incidence of
true contact sensitivity is low, and benzoyl peroxide very rarely produces
photosensitivity. Water-based benzoyl peroxide preparations with concentrations
between 2.5% and 5.0% have been found to less irritating than preparations
based in alcohol, but lost none of its potency. Perhaps the most disadvantage
(not side effect) that a user has to be aware of is that benzoyl peroxide
can bleach clothing and bedding.
A study was conducted recently to compare the efficacy of different gel
benzoyl peroxide concentrations. A 2.5% formulation was as effective as
5% and 10% formulations, and less drying than both in reducing inflammatory
lesions. Significant reductions of acne were seen after two weeks of application.
Side effects were also less frequent and severe in the 2.5% and 5% formulations
as opposed to the 10% formulation.
Combination Therapy
Antibiotic treatment has been known to induce bacterial resistance,
reducing the efficacy of medication. The sharp increase of bacterial
resistance to antibiotics in acne patients led experts to attempt
using benzoyl peroxide in combination therapy.
Adding benzoyl peroxide to a topical drug that reduces bacterial resistance,
for instance, is now a common combination treatment. Such treatment has
been found to be more effective, as well as better tolerated, than if benzoyl
peroxide was applied on its own. In one particular study, no changes were
observed on an acne patient after applying 5% benzoyl peroxide gel twice
daily for four weeks; however, the combination of erythromycin 3% and benzoyl
peroxide 5% resulted in lowered antioxidant enzyme activities in the leukocytes
of acne spots.
Even in combination therapy, however, benzoyl peroxide’s effectiveness
as an anticomedogenic, antimicrobial and antibacterial agent is limited
by its side effects of dryness and irritation. A 12-week, once-daily combination
therapy of tretinoin 0.1% microsphere gel and benzoyl peroxide 6% cleanser
was shown to be more effective in reducing inflammatory lesions (but not
non-inflammatory ones), as opposed to using the tretinoin 0.1% microsphere
gel alone, without any increase in local skin irritation.
Pre-mixed benzoyl peroxide combinations have recently made their way to
drugstore shelves. Unlike older preparations that required refrigeration,
these new formulations are stable at room temperature. Examples of pre-mixed
benzoyl peroxide combinations include the following:
- Erythromycin 3% and benzoyl peroxide 5%
- Clindamycin 1% and benzoyl
peroxide 5%
In patients with moderate to moderately severe acne, the latter sample
was shown to reduce inflammatory and non-inflammatory lesions by 53% and
25% respectively after 11 weeks of treatment, with few side effects.
