What is Atovaquone: Uses, Dosage, Side Effects and More

Atovaquone is an antiprotozoal medication that fights specific parasites in your body. It's commonly prescribed to treat or prevent serious infections like pneumocystis pneumonia (PCP) and malaria, particularly when other treatments aren't suitable for you.

This medication works differently from typical antibiotics because it targets parasites rather than bacteria. Your doctor might prescribe it if you have a weakened immune system or if you're traveling to areas where malaria is common.

What is Atovaquone Used For?

Atovaquone primarily treats and prevents two main types of parasitic infections. The most common use is for pneumocystis pneumonia, a serious lung infection that often affects people with compromised immune systems.

Your doctor might prescribe atovaquone if you have HIV/AIDS, are undergoing chemotherapy, or take medications that suppress your immune system. It's also used to prevent malaria when you're traveling to regions where the disease is prevalent, especially if you can't take other antimalarial drugs.

In some cases, doctors prescribe atovaquone for toxoplasmosis, another parasitic infection that can be particularly dangerous for pregnant women and immunocompromised individuals. This medication serves as an alternative when first-line treatments cause intolerable side effects or aren't effective.

How Does Atovaquone Work?

Atovaquone works by disrupting the energy production inside parasites, essentially starving them of the power they need to survive. It interferes with their mitochondria, which are like tiny power plants inside cells.

This medication is considered moderately strong and specifically targets certain parasites while generally leaving your body's healthy cells alone. Unlike broad-spectrum antibiotics, atovaquone has a focused action that makes it particularly effective against protozoan parasites.

The drug concentrates in tissues where these parasites typically hide, such as your lungs in the case of pneumocystis pneumonia. This targeted approach helps explain why it's so effective for specific infections while causing fewer widespread side effects than some other antimicrobial medications.

How Should I Take Atovaquone?

You should always take atovaquone with food, preferably a meal that contains some fat. Taking it on an empty stomach can reduce how much medication your body absorbs by up to 50%, making it much less effective.

The suspension form should be shaken well before each dose, and you can take it with milk, a meal with butter, or foods like peanut butter to improve absorption. If you're taking tablets, swallow them whole with a full glass of water during or right after eating.

Try to take your doses at the same times each day to maintain steady levels in your bloodstream. If you have trouble keeping the medication down due to nausea, eating smaller, more frequent meals and taking the dose with crackers or toast might help.

Avoid taking atovaquone with antacids or calcium supplements at the same time, as these can interfere with absorption. If you need these medications, space them at least two hours apart from your atovaquone dose.

How Long Should I Take Atovaquone For?

The duration of atovaquone treatment depends entirely on what infection you're treating or preventing. For pneumocystis pneumonia treatment, you'll typically take it for 21 days, while prevention might require longer-term use.

If you're using atovaquone for malaria prevention, you'll usually start taking it one to two days before traveling to an affected area. You'll continue taking it daily while you're there and for seven days after returning home.

For toxoplasmosis treatment, the course might last several weeks to months, depending on the severity of your infection and how well you respond. Your doctor will monitor your progress and adjust the duration based on your specific situation.

Never stop taking atovaquone early, even if you feel better, unless your doctor specifically tells you to. Stopping too soon can allow the infection to return or develop resistance to the medication.

What Are the Side Effects of Atovaquone?

Most people tolerate atovaquone well, but like any medication, it can cause side effects. The good news is that serious side effects are relatively uncommon with this medication.

Here are the most common side effects you might experience:

• Nausea and vomiting
• Diarrhea or loose stools
• Stomach pain or cramping
• Headache
• Dizziness
• Fatigue or weakness
• Trouble sleeping
• Skin rash

These side effects are usually mild and often improve as your body adjusts to the medication. Taking atovaquone with food can help reduce stomach-related side effects.

Less common but more serious side effects that require immediate medical attention include:

• Severe allergic reactions with difficulty breathing or swelling
• Severe diarrhea that doesn't stop
• Signs of liver problems like yellowing of skin or eyes
• Unusual bleeding or bruising
• Severe skin reactions or widespread rash

If you experience any of these serious side effects, contact your healthcare provider immediately or seek emergency care.

Who Should Not Take Atovaquone?

Atovaquone isn't suitable for everyone, and certain health conditions or situations make it inappropriate or potentially dangerous. Your doctor will carefully consider your medical history before prescribing this medication.

You should not take atovaquone if you're allergic to it or have had a severe reaction to it in the past. People with severe liver disease may also need to avoid this medication or use it with extreme caution.

Special precautions are needed if you have:

• Kidney disease or reduced kidney function
• Gastrointestinal disorders that affect absorption
• A history of severe diarrhea or malabsorption
• Pregnancy or breastfeeding (discuss risks and benefits with your doctor)

Your doctor will weigh the benefits against potential risks in these situations and may recommend alternative treatments or closer monitoring if atovaquone is necessary.

Atovaquone Brand Names

Atovaquone is available under several brand names, with Mepron being the most commonly prescribed in the United States. This brand name suspension is often what you'll receive from your pharmacy.

You might also encounter atovaquone in combination medications, such as Malarone, which combines atovaquone with proguanil for malaria prevention and treatment. This combination is particularly popular for travelers.

Generic versions of atovaquone are also available and work just as effectively as brand-name versions. Your pharmacist can help you understand which version you're receiving and ensure you're taking it correctly.

Atovaquone Alternatives

Several alternatives exist for atovaquone, depending on what condition you're treating. For pneumocystis pneumonia, trimethoprim-sulfamethoxazole (Bactrim) is often considered the first-line treatment when tolerated.

Other alternatives for PCP include pentamidine, dapsone with trimethoprim, or clindamycin with primaquine. Your doctor will choose based on your specific situation, allergies, and how well you've responded to previous treatments.

For malaria prevention, alternatives include doxycycline, mefloquine, or chloroquine (in areas without resistance). The choice depends on where you're traveling, your medical history, and potential drug interactions.

If you're treating toxoplasmosis, alternatives might include sulfadiazine with pyrimethamine, clindamycin, or azithromycin. Your doctor will consider the severity of your infection and your ability to tolerate different medications.

Is Atovaquone Better Than Trimethoprim-Sulfamethoxazole?

Atovaquone and trimethoprim-sulfamethoxazole (TMP-SMX) are both effective for treating pneumocystis pneumonia, but they work differently and have distinct advantages. TMP-SMX is generally considered the gold standard and first-line treatment when you can tolerate it.

Atovaquone often becomes the preferred choice when you can't take TMP-SMX due to allergies, severe side effects, or drug interactions. It typically causes fewer serious side effects and is better tolerated by people with sulfa allergies.

Studies show that both medications are similarly effective for treating PCP, though TMP-SMX might have a slight edge in severe cases. However, atovaquone's gentler side effect profile makes it an excellent alternative for long-term prevention.

Your doctor will choose the best option based on your specific circumstances, including your medical history, current medications, and how well you've tolerated similar drugs in the past.