Doxycycline for Acne: How It Works, Dosage, Side Effects and More

• Doxycycline is an antibiotic that is typically prescribed for moderate to severe acne
• It is also used to treat mild forms of inflammatory acne that fails to respond to other treatments
• To increase effectiveness and safety, doxycycline is usually combined with other acne treatments
• Doxycycline is usually taken for three to four months

Acne is a common skin condition that can cause significant distress and long-lasting skin damage if left untreated. Symptoms can range from mild (pimples, blackheads and whiteheads) to severe (papules, pustules and nodules). While effective treatment can be a challenging and lengthy undertaking, doxycycline for acne has earned the reputation as one of the most effective acne medications available.

What Is Doxycycline?

Doxycycline is an oral antibiotic that belongs to a class of medications called tetracyclines which are broad-spectrum antibiotics. This means they can destroy a wide range of bacteria, making them effective against infections such as pneumonia and chlamydia.  

Doxycycline also has anti-inflammatory properties and is commonly prescribed to treat rosacea, also known as adult acne.

This antibiotic can also effectively kill infections caused by gram-positive and gram-negative bacteria. 

How Doxycycline Works to Treat Acne

Doxycycline helps treat acne in several ways. It prevents the bacteria associated with acne, Cutibacterium acnes (formerly Propionibacterium acnes) from multiplying. By inhibiting the multiplication of C. acnes, doxycycline helps to restore the balance of the skin microbiome. The microbiome refers to trillions of microorganisms that are invisible on the skin that support skin health. 

Doxycycline also has anti-inflammatory properties. By inhibiting certain proinflammatory enzymes and acting as an antioxidant, it can reduce the inflammation associated with acne.

How to Use Doxycycline for Acne

Doxycycline should not be taken as a standalone therapy for acne for several reasons. 

While it is effective against inflammation and bacteria, it can do little to address oil, debris and dead skin cells – the material that blocks pores and causes blemishes to form.

Adding other medications such as topical retinoids and benzoyl peroxide can work alongside doxycycline to clear blocked pores. Lastly, using doxycycline with a nonantibiotic medication reduces the risk of developing antibiotic resistance.

You will likely be prescribed doxycycline for 3 months and then your dermatologist will re-evaluate your treatment based on the severity of your acne and your skin’s response. Some patients may need a longer course of doxycycline.

Dosage

The typical dose of doxycycline for acne is 50–100 mg twice daily or 100 mg once daily. Because it can cause an upset stomach and digestive problems, it should be taken with food. 

Concerns over the emergence of antibiotic-resistant strains of bacteria have led some experts to suggest smaller doses of 20 mg twice daily or 40 mg once daily. At this range, doxycycline retains its anti-inflammatory effects and is proven effective against moderate inflammatory acne.

How to deal with the purging stage

As with other acne medications, for the first 4–6 weeks of treatment your symptoms are likely to worsen before they improve. This is known as purging, and is due to increased skin cell turnover and accelerated release of deep-seated comedones.

During this stage, be especially gentle with your skin so that you don’t irritate it further. Avoid all abrasive topical skin care products and opt for a sulfate-free cleanser and a light moisturizer. 

You should not stop taking doxycycline without professional advice. If symptoms persist or worsen, consult with your dermatologist.

Follow a few simple rules to ensure you don’t further irritate your skin during this time:

• Do not pick or pop any lesions; avoid touching the face altogether to practice good hygiene
• Avoid heavy makeup and oily skin care products which could exacerbate your acne
• Change your pillowcase regularly to prevent the transfer of oil and debris to your face
• Stay consistent with your skin care regimen to clear your pores of oil buildup 

Results

Doxycycline is a mainstay acne treatment proven to effectively treat acne and is a component of a first-line treatment regimen for moderate to severe inflammatory acne.

As part of the tetracycline class, it may be superior to other antibiotics because of its antibacterial and anti-inflammatory properties.

A review of multiple clinical trials found that doxycycline successfully reduced up to 75% of inflammatory acne lesions and up to a 54% of comedones (blackheads and whiteheads).

Doxycycline is not an effective treatment against acne scars as they are no longer actively inflamed.

How long does it take to work?

The optimal combination therapy of doxycycline, benzoyl peroxide and a topical retinoid can produce improvements in as little as 2 weeks. However, it can take some people up to 12 weeks to see improvements. 

Acne before and after doxycycline

Interactions and Side Effects

It is particularly important to avoid the sun and apply a protective layer of sunscreen, as doxycycline can cause skin sensitivity resulting in rash, itchiness, redness and sunburn.

Some drugs can decrease the absorption of doxycycline into the body, rendering it less effective including:

• Antacids
• Certain antibiotics such as rifampin
• Iron supplements and multivitamins with iron
• Minerals and vitamins such as calcium, iron and zinc
• Seizure medications such as barbiturates, carbamazepine and phenytoin

Special care and monitoring should be exercised when combining doxycycline with the following drugs:

• Aminolevulinic acid (ALA) can cause an increased risk of skin reactions
• Blood thinners such as warfarin can increase the risk of bleeding 
• Some retinoids such as isotretinoin can cause elevated pressure in the brain  

Other medications may also interact with doxycycline; ensure your dermatologist is aware of all prescription and over-the-counter drugs you are taking. 

Side effects

Some common side effects can occur and include:

• Esophagitis (inflammation of the esophagus) which can manifest as heartburn or chest discomfort; as a preventative, take doxycycline with a full glass of water and avoid lying down for 30 minutes afterward
• Loss of appetite, diarrhea, nausea or vomiting
• Photosensitivity (increased susceptibility to sunburns)
• Rash

Other side effects

Rare, but more serious adverse effects include:

• Permanent damage to teeth and bones in children and infants when doxycycline is ingested during pregnancy 
• Stevens-Johnson syndrome and toxic epidermal necrolysis (TEM), severe skin reactions that cause the skin to blister and peel off

Alternatives

Antibiotic therapy is a cornerstone in the management of acne. Other antibiotics shown to be effective in fighting acne include macrolides, trimethoprim and other members of the tetracycline family.

Tetracyclines

Just like doxycycline, minocycline and tetracycline (named after the group) are all effective acne treatments. (Doxycycline and minocycline have replaced the older tetracycline as the drugs of choice in severe and moderate acne.)

Doxycycline and minocycline are comparable in effectiveness; however, doxycycline is less likely to cause side effects such as gastrointestinal upset.

Macrolides

Macrolide antibiotics such as erythromycin and azithromycin are effective acne treatments and have significant anti-inflammatory effects. Macrolides are prescribed as alternatives for people who cannot take doxycycline due to allergies or severe side effects, pregnancy or young age. 

Trimethoprim

While trimethoprim-sulfamethoxazole (TMP-SMX) is an effective antibiotic for acne, the potential for severe side effects such as suppression of bone marrow function and TEN limit its use.

With that in mind, TMP-SMX is recommended as a third-line antibiotic for treatment-resistant acne or for those who cannot take tetracycline antibiotics.

Takeaway

Doxycycline is a very effective antibiotic with anti-inflammatory properties that is prescribed as a first-line treatment for moderate to severe inflammatory acne. It is also prescribed for mild forms of acne when conventional treatments are ineffective.

For maximum results and safety, doxycycline is typically combined with other acne treatments such as topical retinoids and benzoyl peroxide, another mainstay in acne treatment. 

Doxycycline is usually taken once or twice daily for 3–4 months and it can take several weeks to see improvements. Should you experience side effects, contact your doctor to discuss alternative treatments.