What Is Doxycycline?

Doxycycline is a widely used prescription antibiotic that belongs to the tetracycline class of drugs. It has been available for decades and remains one of the most prescribed antibiotics in the United States. Doxycycline works by stopping bacteria from growing and multiplying, which helps your immune system fight off infections.

Doxycycline is available as a generic medication, making it affordable for most patients. It is also sold under several brand names including Vibramycin, Doryx, Oracea, Adoxa, and Monodox. To learn exactly how it works at the cellular level, check out our plain-English guide to Doxycycline's mechanism of action.

What Does Doxycycline Treat?

Doxycycline is used to treat a wide range of conditions. Here are the most common uses:

Infections

• Respiratory infections — bacterial pneumonia and bronchitis
• Urinary tract infections (UTIs)
• Sexually transmitted infections — chlamydia, gonorrhea, syphilis
• Lyme disease — Doxycycline is the first-choice treatment for early Lyme disease
• Rocky Mountain spotted fever and other tick-borne illnesses
• Cholera, plague, and anthrax — used for treatment and prevention

Skin Conditions

• Acne — one of the most common uses. Doxycycline reduces inflammation and kills acne-causing bacteria.
• Rosacea — the brand Oracea uses a low dose specifically for rosacea

Prevention

• Malaria prevention — taken daily before, during, and after travel to areas where malaria is common
• Anthrax exposure — used as preventive treatment after potential exposure

Doxycycline Dosage

Your doctor will determine the right dose based on what condition is being treated. Here are typical dosages:

• Most infections: 100 mg twice daily (every 12 hours), or 200 mg once daily
• Acne: 50 mg to 100 mg once or twice daily
• Rosacea (Oracea): 40 mg once daily
• Malaria prevention: 100 mg once daily, starting 1 to 2 days before travel
• Lyme disease: 100 mg twice daily for 10 to 21 days
• Chlamydia: 100 mg twice daily for 7 days

Doxycycline comes in several forms including capsules (50 mg, 75 mg, 100 mg, 150 mg), tablets, delayed-release tablets, and liquid suspensions. The most commonly prescribed form is generic Doxycycline Hyclate 100 mg capsules.

How to Take Doxycycline

Getting the most out of your Doxycycline means taking it correctly:

• Take with a full glass of water — at least 8 ounces
• You can take it with food — unlike older tetracyclines, Doxycycline absorbs well with food. Taking it with a meal can reduce nausea.
• Stay upright for 30 minutes — do not lie down right after taking it to avoid irritating your esophagus
• Avoid dairy, antacids, and iron supplements within 2 hours — calcium, aluminum, magnesium, and iron can reduce absorption
• Take it at the same time each day — this keeps levels consistent in your body
• Finish your entire course — even if you feel better, stopping early can lead to antibiotic resistance

Common Side Effects

Most people tolerate Doxycycline well. The most common side effects include:

• Nausea and stomach upset
• Diarrhea
• Sun sensitivity (photosensitivity) — wear sunscreen daily
• Esophageal irritation
• Headache
• Vaginal yeast infections

For a complete breakdown of what to watch for, read our detailed Doxycycline side effects guide.

Who Should Not Take Doxycycline?

Doxycycline is not right for everyone. You should not take it if you:

• Are allergic to tetracycline antibiotics
• Are pregnant or planning to become pregnant (it can harm the developing baby)
• Are breastfeeding (discuss with your doctor)
• Are taking isotretinoin (Accutane) — the combination increases the risk of a serious condition called intracranial hypertension

Children under 8 should generally avoid Doxycycline due to the risk of permanent tooth discoloration, though exceptions are made for serious infections like Rocky Mountain spotted fever.

Drug Interactions

Doxycycline interacts with several common medications and supplements. Major interactions include antacids, iron supplements, Warfarin (blood thinners), and isotretinoin. For the full list, see our Doxycycline drug interactions guide.

How Much Does Doxycycline Cost?

Generic Doxycycline is one of the more affordable antibiotics available:

• With insurance: Typically $0 to $15 copay (Tier 1 on most formularies)
• Without insurance (cash price): $15 to $45 for a typical course
• With a discount card: As low as $8 to $15

Brand-name versions like Doryx and Oracea are much more expensive ($400 to $700+). In most cases, generic Doxycycline works just as well. For tips on reducing costs, read our guide to saving money on Doxycycline.

Doxycycline Availability in 2026

Doxycycline has experienced intermittent shortages over the past several years, with a significant shortage in 2023-2024. Supply has improved in 2026, but some formulations may still have limited availability. If you are having trouble finding it, MedFinder can help you locate a pharmacy with Doxycycline in stock. For the latest, check our 2026 shortage update.

Bottom Line

Doxycycline is a versatile, effective, and affordable antibiotic used to treat everything from acne to Lyme disease to malaria prevention. When taken correctly, it is safe and well tolerated for most people. Talk to your doctor about whether Doxycycline is the right choice for your condition.

Ready to fill your prescription? Use MedFinder to find Doxycycline at a pharmacy near you.