What You Should Know Before Taking Doxycycline for Acne

There's no shortage of topical acne treatments and products out there, and it seems like new ones crop up daily. Patches, washes, scrubs, peels—take your pick. Still, as anyone who has ever dealt with severe acne (we're not talking about the occasional breakout here and there) will tell you, sometimes over-the-counter skincare products simply don't cut it. Often even prescription topical treatments don't cut it. And in that case, dermatologists will try combating the condition from the inside out, which is where oral medications come into play. There are several different options skin docs commonly rely on, ranging from hormonal therapies (birth control pills, spironolactone) to antibiotics. Among the latter, doxycycline—or doxy, as it's often referred to—is one of the most popular, often-prescribed pills out there. Ahead, dermatologists explain why that is, how doxycycline works, and exactly what you need to know before taking it.

Keep reading for more information on this oral acne medication.

What Is Doxycycline?

"Doxycycline is an antibiotic in the tetracycline family that is commonly used to treat a variety of bacterial infections, as well as moderate to severe acne," explains Zeichner. The 'moderate to severe' part is key here, as this is not (nor is any oral antibiotic) a go-to treatment for a few clogged pores or blackheads. It should only be considered for those suffering from inflammatory acne; in other words, widespread, red, angry pimples, notes Zeichner. It's also especially useful for those dealing with acne on larger areas of the body—think the chest and back—as well as for patients who aren't responding to topical medications alone, he adds.

Its mechanism of action against acne (more on that in a moment) is similar to that of other tetracycline antibiotics, the most common being minocycline. That being said, "doxycycline is the most commonly used oral antibiotic for acne due to its low side effect profile and efficacy in treating inflammatory acne," says Carqueville. Zeichner agrees: "It's an effective drug that has been used in dermatology for decades and has a proven safety record." Doxycycline is the generic name of the drug, by the way, and name brands include Vibramycin, Mondox, Atridox, and Doryx, to name a few.

How Doxycycline Works for Acne

So, how exactly does it help combat blemishes? "Doxycycline treats acne in both direct and indirect ways," says Zeichner:

Lowers levels of acne-causing bacteria: The medication directly lowers the levels of acne-causing bacteria (p.acnes) on the skin. Like the other tetracyclines, it does this by inhibiting the protein synthesis of this bacteria, explains Carqueville. The other benefit of this? Reduced bacterial levels also reduce subsequent inflammation in the skin, points out Zeichner.

Impacts the immune system: Doxy also reduces inflammation more directly via its effects on the immune system. (It is worth pointing out, however, that this isn't a benefit exclusive to doxycycline, but rather something all tetracycline antibiotics do, as shown in a 2007 study). "It blocks the recruitment of inflammatory blood cells and enzymes and messengers that drive skin inflammation," Zeichner explains. This double-whammy of anti-inflammatory benefits is why this drug reduces the redness and tenderness of active pimples, adds Carqueville.

How to Use Doxycycline

At the risk of pulling a Captain Obvious, you'll first have to get a prescription from your dermatologist. It's extremely important only to take this medication under the direct guidance of a dermatologist, as it can have some serious side effects (more on that below).

"The dosage and duration of treatment may vary from patient to patient, but typically you can expect to be on the medication for at least six to eight weeks. The dosage is usually 50 to 100 milligrams, taken once or twice daily," says Carqueville. Doxycycline can have some gastrointestinal side effects, so both of the dermatologists we spoke with also advise taking the medication with a full glass of water. Also important: Take it at least 30 minutes, if not an hour, before lying down to minimize the risk of developing heartburn. It's a no-no if you're pregnant or breastfeeding, as well as for anyone who is allergic to tetracyclines.

Zeichner also suggests talking to your dermatologist about combining oral doxy with a product that contains benzoyl peroxide, a topical ingredient that also has antibacterial activity against p.acnes—this can help limit the development of bacterial resistance, he adds. And to that point, keep in mind that this isn't going to be a long-term treatment. While you do need to be on it for several weeks to see effects, "it should be limited to three or four months of use, and discontinued as soon as possible," cautions Zeichner. This is the general rule of thumb for any oral antibiotic being used as an acne treatment, again, in order to minimize the likelihood of bacterial resistance. Once you're off of it, topical treatments should be enough to maintain the results achieved. If not, your dermatologist will likely suggest an alternative oral drug, such as hormonal therapy or a heavy-duty medication called isotretinoin, Zeichner says.

Potential Side Effects

We mentioned heartburn, and that is one of the biggest potential side effects. "Doxycycline can cause inflammation of the esophagus and in severe cases even lead to ulcers," says Zeichner. Nausea and vomiting are also possible side effects, as is increased sun sensitivity, so be extra diligent about your sun protection practices, advises Carqueville. Still, it's worth noting that even though a study published in the Journal of the American Academy of Dermatology found both doxycycline and minocycline to be effective acne treatments, the side effect profile is theoretically safer and more tolerable with doxy, according to Carqueville. (She adds that while there tend to be fewer GI symptoms that come with minocycline, it may be associated with rare hypersensitivity reactions and ringing in the ears, which aren't side effects of doxycycline.) In other words, while this may sound like a long list of potentially unpleasant side effects, at the end of the day, doxycycline is still considered to be a top-notch safe and effective oral antibiotic for acne.