Antibiotics for Acne
What is Acne?
Acne (also called acne vulgaris) is a common skin disease characterized by clogged pores and pimples, blackheads, or red, swollen bumps. Acne lesions are most common on the face, but they can also occur on the neck, chest, back, shoulders, scalp, and upper arms. Acne lesions are referred to as pimples, spots, or zits.
More than four out of five people between the ages of 12 and 24 have acne at least once. But while acne is often associated with teenagers, it can affect people of all ages.
Acne is rarely a serious medical condition, but it often causes emotional distress and can lead to scarring of the skin.
Acne occurs when the hair follicles become plugged with oil and dead skin cells. However, the exact cause why some people get acne and some do not is unknown.
Types of Acne
When to expect improvement?
Whichever treatment is used, it is normal to take up to 4 weeks to see any noticeable improvements. There is often a good response by 6 weeks. However, it can take up to 4 months (sometimes even longer) for maximum response, and for the skin to be generally free of spots.
The main reason for a treatment failure is because some people think that it is not working after a couple of weeks or so, and give up.
How long to take antibiotics for acne?
Once the spots have cleared, acne commonly flares up again if you stop the treatment. Therefore, after the spots have gone or are much reduced, it is better to carry on with a 'maintenance' treatment to prevent acne from flaring up again.
The maintenance treatment may continue for 4-5 years to keep acne away. This is typically until the late teens or early 20s. Sometimes, acne persists into the 30s, or even later. For these people it is possible to continue maintenance treatment with a topical benzoyl peroxide or a topical retinoid.
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. Antibiotics also work by decreasing the redness and swelling seen in the inflammatory forms of acne.
However, antibiotics have little effect on unplugging blocked pores, which are blackheads and whiteheads.
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 acne.
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 anti-inflammatory effect and alter sebum excretion, resulting in a decreased accumulation of follicular free fatty acids.
Tetracyclines should be avoided by pregnant and or breast-feeding women as they cause discoloration and enamel hypoplasia of developing milk-teeth. They should not be taken by children younger than 8 years of age because they can affect growth and stain developing permanent teeth.
Tetracycline is the most widely prescribed antibiotic for acne. The main drawback of tetracycline is that it must be taken on an empty stomach to be the most effective. For a teenage boy who eats frequently, this can be very difficult.
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 rhe pilosebaceous unit.
Doxycycline is better tolerated than tetracycline. However, it is more likely to increase sensitivity to the sun, or cause sunburns.
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. Lymecycline very popular among dermatologists in France, Italy, and Nordic countries.
Trimethoprim-Sulfamethoxazole (Co-trimoxazole, Bactrim®) may be a reasonable treatment for refractory acne. It is not approved by the US FDA for the treatment of acne vulgaris.
Sulfamethoxazole use in dermatologic conditions is limited because of fear of 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 twice daily.
Given the growing resistance of P. acnes, oral erythromycin is usually reserved for acne during pregnancy, breastfeeding, or young children.
Dosage: 500 mg twice daily.
Azithromycin has been widely prescribed to treat acne in recent years.
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.
Although effective, oral clindamycin is rarely used to treat acne because of potentially serious side effects. 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.
Antibiotics may be taken orally or applied to the skin in the form of gels and lotions. Giving an antibiotic by mouth is often needed for acne that is more extensive, red, and tender.
Topical antibiotics work by killing the Propionibacterium acnes bacteria. This also indirectly keeps the pores open.
Clindamycin (Cleocin-T®, Clinda-Derm®)
Topical clindamycin has a long history of successfully treating acne. It works by killing P. acnes and decreasing inflammation. In topical form, clindamycin has proven to be safe and is well tolerated. Skin dryness and irritation are possible troubles. It is important to use clindamycin as directed to decrease bacterial resistance that can occur with antibiotic.
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®)
Clindamycin phosphate 1.2% plus tretinoin 0.025% gel was approved by the FDA in 2006 for the treatment of acne vulgaris. This product combines the anti-inflammatory and antibacterial properties of clindamycin with the well proven beneficial comedolytic effects of tretinoin, with a low incidence of irritation4.
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.
Antibiotics NOT recommended for acne
References & Resources
Published: July 20, 2009