If you have to take an antibiotic, you might wonder if it will interact with your lupus symptoms and medications. “Has anybody been on doxycycline? If so, how did you do?” asked one MyLupusTeam member.

Antibiotics, such as doxycycline, are medications that fight bacterial infections. Because lupus can increase your risk of infection, you’ll likely be prescribed an antibiotic at some point. Here are six facts that people with lupus should know about antibiotics.

1. Lupus Raises Your Risk of Infections in Two Ways

People with lupus have an increased risk of infections for two main reasons — the disease itself and the medications that treat it.

Normally, your immune system helps protect you from germs like bacteria and viruses. But if you have lupus, this autoimmune disease causes your immune system to mistakenly attack healthy body tissue.

Lupus can cause organ damage when your immune system becomes overactive. It may seem like this heightened action would protect you from infections, but this isn’t the case. Instead, overactive immune cells cause your body to make proteins called antibodies that can attack your immune system, leaving it less able to protect you from germs.

Many people with lupus take immunosuppressive medications, which can be helpful because they stop your immune system from going after healthy tissue. However, these drugs can also stop your immune system from effectively attacking germs. Common immunosuppressive medications used for lupus treatment include:

• Methotrexate (Rheumatrex)
• Mycophenolate mofetil (CellCept)
• Azathioprine (Imuran)
• Cyclophosphamide (Cytoxan)
• Voclosporin (Lupkynis)

Up to half of people diagnosed with systemic lupus erythematosus (SLE), the most common type of lupus, are hospitalized for a serious infection at some point. People with lupus nephritis (kidney disease caused by SLE) may have an even higher risk of serious infections.

2. Antibiotics Treat Bacterial Infections

Antibiotic drugs help you fight harmful bacteria, tiny germs that live in your body, on your skin, and on your surroundings. Most bacteria are harmless and even help you stay healthy. However, some types of bacteria can cause sickness, ranging from a minor illness to one that requires hospitalization.

Your immune system acts as your natural protection against bacteria, but sometimes it needs extra help, especially if it’s weakened. Antibiotics can help your body clear an infection by killing the bacteria or stopping them from multiplying.

The most common types of infections in people with lupus are:

• Respiratory infections (involving the lungs and airways)
• Skin infections
• Urinary tract infections (involving the kidneys or bladder)

Doxycycline (Vibramycin), a tetracycline antibiotic, is one of the most commonly prescribed antibiotics in the United States. This drug can be used to treat respiratory and skin infections, as well as conditions such as:

• Acne, rosacea, and other skin conditions
• Periodontitis and other dental infections
• Lyme disease
• Sexually transmitted infections

Other commonly prescribed antibiotics include:

• Amoxicillin (Amoxil)
• Amoxicillin/clavulanic acid (Augmentin)
• Azithromycin (Zithromax)
• Cephalexin (Keflex)

The effectiveness of doxycycline or another antibiotic depends on the type of bacteria causing the infection. Different antibiotics target different types of bacteria. Your health care provider will prescribe an antibiotic that specifically fights the type of bacteria causing your illness.

3. Antibiotic Side Effects Might Worsen Lupus Symptoms

Some antibiotics can act as an environmental trigger that prompts a lupus flare. Common antibiotics that can trigger flares include:

• Sulfamethoxazole-trimethoprim (Bactrim, Septra)
• Tetracycline antibiotics like doxycycline and minocycline (Minocin)
• Penicillins like amoxicillin and ampicillin (Principen)

Additionally, the side effects of some antibiotics can be similar to lupus symptoms, making it hard to pinpoint what’s behind a flare.

Skin Conditions

Most people with lupus have symptoms that affect their skin, including sensitivity to the sun. This photosensitivity can also be caused by certain antibiotics, such as:

• Doxycycline
• Ciprofloxacin (Cipro)
• Levofloxacin (Levaquin)
• Sulfamethoxazole-trimethoprim

If you take one of these antibiotics, be especially diligent about wearing sunscreen and sun-protective clothing.

Some antibiotics can cause rashes as a side effect or an allergic reaction. Use of doxycycline can have other possible skin side effects like:

• Serious rashes
• Peeling
• Blisters
• Discoloration

Antibiotic allergies are rare but can be serious when they do happen. Skin reactions are the most common symptom of antibiotic allergies, which are mostly reported with use of penicillins and sulfa antibiotics.

Before you start taking an antibiotic, talk to your health care provider about your risk of photosensitivity, rashes, and allergic reactions.

Stomach Problems

Digestive system problems are common in people with lupus. Your digestive system — also called your gastrointestinal (GI) system — includes your mouth, esophagus, stomach, intestines, gallbladder, and pancreas. GI problems can be caused by lupus itself or as a side effect of lupus medications, such as prednisone and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Motrin).

Most antibiotics bring a risk of diarrhea, and some can cause additional stomach-related side effects. For example, possible GI side effects of doxycycline include:

• Nausea or vomiting
• Diarrhea
• Stomach pain
• Trouble swallowing

In severe cases, doxycycline can cause an ulcer (open sore) in your stomach or esophagus, especially if you don’t take it with enough water.

Drug-Induced Lupus

Drug-induced lupus, an autoimmune disorder caused by medications, can be a rare side effect of two antibiotics — minocycline and isoniazid (Nydrazid).

Minocycline has been linked to lupuslike symptoms and may worsen existing lupus symptoms. Even though minocycline is a tetracycline antibiotic that’s related to doxycycline and the two drugs treat similar infections, drug-induced lupus caused by doxycycline is less common. The risk is also rare with isoniazid, an antibiotic used to treat tuberculosis — less than 1 percent of people taking isoniazid develop drug-induced lupus, according to findings published in the journal Cureus.

If you experience any changes in your lupus symptoms while taking an antibiotic, talk to your doctor right away.

4. Antibiotics Can Interact With Other Medications

Antibiotics can have drug interactions with prescription and over-the-counter (OTC) medications. If you have lupus-related stomach problems such as heartburn, you might take antacids for relief. It’s important to know that antacids containing calcium, magnesium, or aluminum can make doxycycline less effective. Antacids can also interfere with other antibiotics, including:

• Azithromycin
• Ciprofloxacin
• Levofloxacin

Doxycycline can also interact with cyclosporine (Gengraf, Neoral, Sandimmune), an immunosuppressant that can be used to treat lupus nephritis.

Make sure your health care provider knows about all medications you take, including OTCs and supplements. Check with your doctor or pharmacist about potential drug interactions before you start taking an antibiotic.

5. Antibiotics Must Be Taken Exactly as Instructed

Your doctor will choose an antibiotic for you based on your symptoms, the type of bacteria causing the infection, and potential drug interactions. To make sure you get the safest, most effective treatment, you should talk to your doctor about the following:

• Symptoms of your current illness
• Your lupus triggers
• All medications you take — including prescriptions, OTCs, and supplements
• Any drug allergies

To find out if an antibiotic like doxycycline is safe for you, talk with your doctor.

It’s also important to take antibiotics exactly as instructed. Don’t stop taking them even if you feel better. If you have lupus, you may need a longer course of antibiotic treatment to make sure the infection is gone.

Stopping an antibiotic early, skipping doses, or taking antibiotics that weren’t prescribed for you can lead to antibiotic resistance. This means that if you get sick again, the same antibiotic may not work.

6. Reducing Infection Risk Can Help Prevent Antibiotic Use

Even with antibiotics, it can be hard to treat infections when you have lupus, so it’s important to avoid needing these drugs in the first place.

You can decrease your risk of infections by doing the following:

• Stay up to date with all your vaccinations.
• Wash your hands regularly.
• Wear a mask in crowded places.
• Thoroughly wash all fruits and vegetables before eating them.
• Clean your house regularly.
• Eat a well-balanced diet.

Talk to your health care provider for more information about your risk of infection and how you can prevent bacterial diseases.

Talk With Others Who Understand

On MyLupusTeam — the social network for people with lupus and their loved ones — more than 223,000 members come together to ask questions, give advice, and share their stories with others who understand life with lupus.

Have you taken antibiotics? Did you develop any side effects or take steps to prevent them? Share your experience in the comments below, or start a conversation by posting on your Activities page.