Acne Antibiotics: Types, Side Effects, and Risks

Acne antibiotics, such as doxycycline and minocycline, are medications prescribed for moderate to severe acne that does not respond to other treatments. Acne antibiotics work by decreasing the number of bacteria that become trapped in and around hair follicles and sebaceous glands.

Aside from taming breakouts, antibiotics can help limit consequences like permanent scarring, which occurs in about 20% of people living with severe acne. While effective, these drugs have side effects that should be considered.

This article details the antibiotics commonly used to treat acne and how they work. It presents information about side effects, as well as the growing problem of antibiotic resistance that may affect how and when they're prescribed.

How Acne Antibiotics Work

Acne develops when hair follicles become clogged with an overgrowth of normal skin bacteria, destroying the lining of the follicle. As a result, bacteria and debris enter the dermis (middle) layer of the skin, causing an inflammatory response.

Whether applied topically or taken orally, acne antibiotics stop the growth of acne-causing bacteria on the skin. In doing so, acne antibiotics prevent bacteria from clogging hair follicles and sebaceous glands.

Additionally, some types of acne antibiotics have anti-inflammatory effects that reduce the redness, swelling, and tenderness associated with inflammatory papules, pustules, and nodules.

How Long Does It Take for Acne Antibiotics to Work?

Generally speaking, expect to take oral (by mouth) acne antibiotics for three to four months before you notice significant improvements. The recommended course will, however, differ depending on the medication used and your skin.

Some people may take an antibiotic for much longer, with one study of oral amoxicillin reporting an average duration of 37 weeks. Your dermatologist will ensure they are prescribing a safe and effective treatment.

Doxycycline

Doxycycline is one of the first-line treatments for acne and has replaced tetracycline in popularity.

Oral doxycycline is started at a dose of 50 milligrams (mg) to 100 mg twice a day. It should be taken with food; otherwise, it can cause significant nausea.

Doxycycline is more likely than tetracycline to increase sensitivity to the sun or cause sunburns, a phenomenon known as photosensitivity. There are other acne medications that may cause photosensitivity as well, such as benzoyl peroxide, alpha-hydroxy acids, and topical retinoids.

Doxycycline is available under these brand names: Doryx, Oracea, Monodox, Atridox, Morgidox, Vibra-Tabs, Alodox, Ocudox, Doxy, Acticlate, and Vibramycin.

Tetracycline

Tetracycline was once the most widely prescribed class of acne antibiotics, but it's the tetracycline derivatives like doxycycline and minocycline that are more commonly used today.

There are several antibiotics within the entire class, including tetracycline, which remains available in both 250-mg and 500-mg formulations.

The usual starting dose is 500 mg taken orally twice a day until a significant decrease in acne lesions is seen. The dose can then be decreased to 250 mg twice a day or discontinued.

Tetracycline may cause stomach upset. Eating it with non-dairy foods is often advised, as dairy products decrease absorption and render it less effective.

Tetracycline is available under these brand names: Tetracon, Tetracap, Sumycin, Panmycin, Brodspec, Ala-Tet, Actisite, and Achromycin V.

Minocycline 

Minocin (minocycline) is a tetracycline derivative that has been used effectively for decades as a treatment for acne. It is especially useful for pustular type acne.

While the absorption of minocycline is decreased with food, it is not as significant as the decrease seen with tetracycline. The usual starting dose is 50 mg to 135 mg twice a day.

Although rare, a minocycline-induced headache can be a sign of a serious condition called pseudotumor cerebri, (PTC) in which there is elevated cerebrospinal fluid pressure in the skull. Unless treated promptly, PTC can lead to progressive, and potentially permanent, vision loss.

Minocycline is available under these brand names: Solodyn, Minocin, Dynacin, Ximino, Myrac, and Minolira.

Amoxicillin

Amoxicillin is not considered a first-line drug for treating acne. However, a study of 26 people who were first treated with other antibiotics without success found that 85% of them saw improvement with amoxicillin when used alongside topical treatments and/or hormone therapy.

Compared to other acne antibiotics, amoxicillin typically has fewer side effects, though nausea, diarrhea, and headache can occur.

Amoxicillin is not associated with fetal birth defects when taken by pregnant people. Nonetheless, if you are pregnant or could become pregnant, be sure to inform your healthcare provider when discussing acne antibiotics.

Because it's in the penicillin class of antibiotics, it can't be used in people with penicillin allergies. However, it may be a good option for people with allergies to doxycycline and other first-line drugs. A daily dose of 1000 mg, or 1500 mg in more serious acne cases, appears to work well.

Amoxicillin is available under these brand names: Amoxicot, Amoxil, DisperMox, Moxilin, and Trimox.

Septra/Bactrim and Macrolides

Septra or Bactrim (sulfamethoxazole/trimethoprim) and Zithromax (azithromycin) a macrolide, have often been used to treat moderate to severe inflammatory acne.

Studies do not seem to favor one acne antibiotic over another with this condition, but treatment appears to work much better when combined with topical therapy.

Topical Antibiotics

Clindamycin is most widely prescribed as a topical antibiotic. While clindamycin does come in an oral form to treat acne, it is much more commonly prescribed in topical form.

The major side effect of oral clindamycin therapy is a serious intestinal infection called pseudomembranous colitis caused by the bacteria Clostridioides difficile (C. difficile or C. diff).

A C. difficile infection is much more common with oral clindamycin but has been reported with the topical product as well.

Topical clindamycin is available under the brand names Cleocin-T, Clinda-Derm, Clindagel, Clindets, C/T/S, and Evoclin.

Antibiotic Side Effects

All antibiotics can cause vaginal yeast infections. Tetracycline seems to be the antibiotic that most frequently has this side effect.

All oral antibiotics can also lessen the effectiveness of birth control pills, so a backup birth control method is needed. Nausea is fairly common with erythromycin and doxycycline.

Concerns About Antibiotic Resistance

In recent years, healthcare professionals have been seeing increasing resistance of the bacteria Propionibacterium acnes against the oral antibiotics used.

Current strategies to reduce resistance recommend using antibiotics in combination with topical treatments and limiting the duration of use when possible. This, however, has impacted the overall effect of antibiotics on acne.

As is the case with prescribing any medication, the risks have to be weighed against the rewards. Discuss all of your options with your healthcare provider.

While short-term use of antibiotics is generally considered best, not finishing a recommended course of one of these drugs can actually contribute to the problem of antibiotic resistance.

Summary

Antibiotics can be very helpful for some people with acne and work by a combination of mechanisms. Some antibiotics work better for particular types of acne and your dermatologist can make the best choice by understanding your history of acne as well as your lifestyle.

As with any medication, side effects may occur. Fortunately, there are several different choices available if one of the above is not helpful.