Antibiotics for Acne
What is Acne?
Acne vulgaris is a disorder of the pilosebaceous follicles of the skin. Acne is characterized by comedones, papules, pustules, cysts and scars.
Types of acne:
Antibiotics for Acne Treatment
Antibiotics are more effective for inflammatory acne, than for non-inflammatory, because they have no effect on unplugging blocked pores, which are blackheads and whiteheads. Antibiotics can be taken orally or applied to the skin in the form of creams, gels and lotions.
When to expect an improvement?
Any acne treatment should be used at least for 4 weeks before there is a noticeable improvement6. There is often a good response by 6 weeks. However, it can take up to 4 months (sometimes even longer) for maximum benefits, and for the skin to be generally free of spots.
The main reason for a treatment failure is because some people think that medication is not working after a couple of weeks, and give up.
How long to take antibiotics for acne?
It is recommended to continue antibiotic therapy for a minimum of 3 months, and 6 months for maximum results6. The treatment may be continued longer until satisfactory improvement is achieved. In some cases, antibiotics can be safely used for up to 4 years7.
Many dermatologists5 recommend a maintenance therapy with a topical benzoyl peroxide or a topical retinoid to prevent acne from flaring up again.
Oral antibiotics are recommended for the treatment of moderate or severe inflammatory acne (papules and pustules). They work by killing the acne causing skin bacteria Propionibacterium acnes and reducing inflammation.
Over time, the P. acnes bacteria can become resistant to the antibiotic being used. Then another antibiotic or alternative treatment can be chosen to control the condition.
Tetracyclines: the best antibiotics for acne
Tetracyclines are the most commonly used antibiotics to treat acne. They produce antibacterial effect by reducing the colonization of P. acnes. Additionally, tetracyclines exert direct anti-inflammatory effect and alter sebum excretion, resulting in a decreased accumulation of follicular free fatty acids.
Tetracyclines are contraindicated in:
Tetracycline is the most widely prescribed antibiotic for acne. The main problem is that tetracycline must be taken on an empty stomach to be fully effective. For persons who eat frequently, this can be very troublesome.
Dosage: The usual starting dose is 500 mg twice a day continued until a significant decrease in acne lesions is seen. The dose can then be decreased to 250 mg twice a day or discontinued.
Doxycycline (Doryx®, Oracea®)
Doxycycline is especially effective in treating inflammatory acne. Doxycycline is more lipophilic than tetracycline and has excellent penetration into the pilosebaceous unit.
Doxycycline is better tolerated than tetracycline. However, it is more likely to increase sensitivity to the sun, or cause sunburns. Therefore doxycycline should thus be used with caution during the summer and in hot climates.
Patients with gastrointestinal problems can take Doryx® -- delayed-release tablets of doxycycline in the form of enteric-coated pellets. Doryx® causes fewer gastrointestinal side effects in comparison to capsules containing the powdered form.
Dosage: 50 to 100 mg twice a day.
SubAntimicrobial dose: 20 mg twice daily. Doxycycline subantimicrobial dosing provides 84-90% reduction in the number of papules and pustules2.
Oracea®, a controlled-release formulation, is dosed 40 mg once daily and may be a more convenient choice.
Minocycline has a long history of use to treat acne. It is the most lipophilic tetracycline, allowing greater penetration into sebaceous follicles. Minocycline is effective in treating acne that has not responded to other oral antibiotics. It is especially useful for pustular type acne.
Minocycline seems to produce fewer incidents of antibiotic resistance. It can be taken with or without food.
Safety concerns: Minocycline is known to cause bluish-gray skin pigmentation, vestibular toxicity, and various autoimmune reactions (lupus, autoimmune hepatitis, serum sickness, vasculitis, and pneumonitis).
Dosage: The usual starting dose is 50 to 100 mg twice a day.
Solodyn® is an extended-release formulation of minocycline for once-daily dosing.
Lymecycline is used outside of the US for acne. It is very popular among dermatologists in France, Italy, and Nordic countries. Lymecycline is generally safe and well tolerated.
Dosage: 300-600 mg of lymecycline daily.
Trimethoprim-Sulfamethoxazole (Co-trimoxazole, Bactrim®) may be a reasonable treatment for refractory acne9. It is not approved by the US FDA for acne vulgaris.
Sulfamethoxazole use in dermatologic conditions is limited because of possible serious adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and blood dyscrasias. In practice these serious side effects are infrequent, the most common side effect being a maculopapular rash.
Dosage: 160 mg/800 mg of trimethoprim/sulfamethoxazole twice daily.
Given the widespread resistance of P. acnes, oral erythromycin is suitable only for acne during pregnancy, breastfeeding, or young children.
Dosage: 500 mg twice daily.
Azithromycin has been widely prescribed to treat acne in recent years10.
Because azithromycin is effective at doses given 1 to 3 times weekly, it may be a good option for adolescents with poor compliance. It is a valid alternative for patients intolerant or unable to take tetracyclines for various reasons.
Dosage: 500 mg once-thrice weekly.
Oral clindamycin is an effective treatment, but it is rarely used to treat acne because of possible serious side effects8. Clindamycin may cause overgrowth of Clostridium diffıcile resulting in pseudomembranous colitis. About 20-30% of patients taking oral clindamycin experience diarrhea.
Dosage: 300 mg 3 times per day.
Topical antibiotics are effective for treating mild to moderate inflammatory acne. Topical antibiotics work by killing the Propionibacterium acnes bacteria. This also indirectly keeps the pores open.
Clindamycin (Cleocin-T®, Clinda-Derm®)
Topical clindamycin is indicated for the treatment of acne. It works by suppression of the growth of P. acnes and decreasing inflammation. In topical form, clindamycin has proven to be safe and is well tolerated11.
Topical clindamycin decrease inflammatory acne lesions better than oral tetracycline12.
Topical clindamycin comes in various vehicles, including gel, lotion, solution and foam.
Clindamycin and Benzoyl Peroxide (Acanya®, BenzaClin®, Duac®)
Clindamycin phosphate 1.2% plus benzoyl peroxide 3% gel has a favourable safety and tolerability, and may be superior than clindamycin alone in the treatment of acne vulgaris3. Clindamycin may work synergistically with benzoyl peroxide by increasing free-radical formation.
Clindamycin and Tretinoin (Ziana®, Veltin®, Biacna™)
Clindamycin phosphate 1.2% plus tretinoin 0.025% gel was approved by the FDA in 2006 for the treatment of acne vulgaris. The gel combines the anti-inflammatory and antibacterial properties of clindamycin with beneficial comedolytic effects of tretinoin4. This combination is very well-tolerated and has a low incidence of irritation. Noticeable improvement in acne is usually seen after 12 weeks of application.
Erythromycin (Akne-mycin®, Erygel®, Ery®)
Topical erythromycin is an antimicrobial and anti-inflammatory. The combination of topical erythromycin with benzoyl peroxide proves to be quite effective. Like topical clindamycin, erythromycin may cause skin dryness and irritation. Erythromycin is safe for use by pregnant women.
Erythromycin and Benzoyl Peroxide (Benzamycin®)
Erythromycin and benzoyl peroxide combination is indicated for the treatment of acne. Benzoyl peroxide is an antibacterial agent with keratolytic and desquamative properties. This combination produces keratolytic and comedolytic effects.
Antibiotics NOT recommended for acne
References & Resources
Published: July 20, 2009