Atovaquone (Oral)

Pneumocystis jiroveci pneumonia (or PCP), is a strain of pneumonia which tends to occur in patients with a poor immune system. Atovaquone, the compound used to treat PCP, works through its antiprotozoal characteristics, inhibiting the growth of those particular protozoa responsible for causing pneumonia. In addition to treating PCP, it is also used for treating toxoplasmosis, babesia, and malaria.


Atovaquone is an antiprotozoal drug used for the treatment of pneumocystis jiroveci pneumonia (otherwise known as PCP). PCP is a strain of pneumonia that affects patients suffering from a weak immune system. This includes people who have undergone organ transplants, or who are currently battling cancer, as well as patients with the human immunodeficiency virus (or HIV). It is also used to treat patients who are unable to take sulfonamide medications.

It is often used to treat mild cases of PCP and is not usually recommended for treating severe cases. It impacts upon the infection by restricted the growth of the specific protozoa that cause pneumonia. Additionally, the drug does not cause myelosuppression, unlike other pneumonia treatments, and this is an important consideration for those patients who have undergone a bone marrow transplant.

Atovaquone also boasts therapeutic and antiparasitic qualities, which makes it effective in the treatment of toxoplasmosis, a widespread parasitic disease that often produces little in the way of symptoms.

Atovaquone is incorporated with another drug, proguanil, to form the malaria medication, Malarone, which is reported to present fewer side effects than the more commonly prescribed mefloquine.

Atovaquone is also often combined with an oral administration of azithromycin for use in the treatment of babesiosis, a parasitic disease that bears malaria-like symptoms. The disease is caused by infection with babesia, a type of parasitic alveolate carried and transmitted by ticks.

Atovaquone is only available as a prescription from the doctor.

Atovaquone is an oral medication, and is available in the following forms:

  • Tablet
  • Suspension

Conditions Treated

  • pneumocystis jiroveci pneumonia (PCP)
  • pneumocystis carinii pneumonia (PCP)
  • toxoplasmosis
  • malaria
  • babesiosis

Type of Medicine

  • antiprotozoal

Side Effects

As with any medication, atovaquone may be responsible for a number of unwanted side effects, along with its intended effects. While not all the side effects listed here might necessarily occur, should any of them do so during your course of treatment, it is possible that they might require medical attention.

If any of these side effects occur during your course of treatment with atovaquone, you should speak to your prescribing doctor immediately:

  • hoarseness or coughing
  • labored or difficult breathing
  • chills or fever
  • side or lower back pain
  • difficult or painful urination
  • tightness to the chest
  • black or tarry stools
  • bleeding gums
  • blood in the stools or urine
  • bloating
  • bluish-colored tinge to the fingernails, palms, or lips
  • constipation
  • darker urine
  • light-headedness or dizziness
  • headache
  • fast heartbeat
  • indigestion
  • large, hive-like swellings appearing on the eyelids, tongue, lips, face, sex organs, hands, feet, or legs
  • light-colored stools
  • nausea
  • noticeable loss of appetite
  • nausea
  • pains in the side, stomach, or abdomen, which may radiate as far as the back
  • noisy breathing
  • red pinpoint spots on the skin
  • pale skin
  • sore throat
  • rapid heart rate
  • unusual or unexpected bruising, or bleeding
  • unusual or unexpected weakness, or tiredness
  • yellow skin or eyes
  • vomiting

As well as the above-listed side effects, some effects might occur that would not normally require medical attention. It is likely that these side effects will go away during your course of treatment as the patient's body adjusts to the medication. Also, your prescribing doctor might be able to advise alternative ways to reduce or prevent some or all of these side effects. If any of the following side effects should continue throughout your course of treatment, or should any of them become bothersome to you, be sure to contact your healthcare professional:

  • stomach or abdominal pain
  • diarrhea
  • loss or lack of strength
  • runny nose
  • rash on the skin
  • sneezing
  • sore tongue or mouth
  • stuffy nose
  • trouble sleeping
  • sweating
  • white patches on the mouth, throat, or tongue
  • peeling, loosening, or blistering of the skin
  • eye redness or irritation
  • itching skin, or attendant rash
  • muscle or joint pain
  • red lesions on the skin, sometimes with a purple center

The above lists are not exhaustive, and there may be some other side effects that exhibit in certain patients that are not listed here. Should you notice any unusual or unexpected effects during your course of treatment with atovaquone, be sure to check with your prescribing doctor.


Your dosage of atovaquone differs from patient to patient, depending on their individual requirements. Always follow directions from your prescribing doctor or the instructions on the label. The information detailed below only includes the average dosage of atovaquone, so if you are prescribed a different amount, you should not alter it unless told to do so by your healthcare professional.

The amount of atovaquone that you are prescribed to take will depend on how strong the medicine is. Likewise, the length of your course of treatment, the time you are expected to let elapse between doses, and the number of doses you are expected to take each day will depend upon the medical condition for which you have been prescribed the medicine.

For the prevention of pneumocystis jiroveci pneumonia (PCP) via oral dosage (suspension):

Adults and children who are 13 years of age or over should take 10 milliliters (mL), or 1500 milligrams (mg) once a day with food.

Children under the age of 13 should only use the amount and frequency of atovaquone as determined by the prescribing doctor.

For the prevention of pneumocystis carinii pneumonia (PCP) via oral dosage (suspension):

Adults and children who are 13 years of age or over should take 5 milliliters (mL), or 750 milligrams (mg) twice a day, with food, for a period of 21 days.

Children under the age of 13 should only use the amount and frequency of atovaquone as determined by the prescribing doctor.

For the prevention of pneumocystis carinii pneumonia (PCP) via oral dosage (tablets):

Adults should take 750 milligrams (mg) three times per day, with food, over a period of 21 days.

Children should only use the amount and frequency of atovaquone as determined by the prescribing doctor.

If you miss a dosage of atovaquone during your prescribed course of treatment, you should take it as soon as you can. However, should it be almost time for you to take your next dose, you should skip the dosage you missed and return to your regular schedule of dosing. Under no circumstances should you double your dose.

You should take atovaquone precisely as directed by your prescribing doctor. You should not use more than the prescribed dose, nor should you use it more frequently, or for a longer term than that ordered by your doctor.

Atovaquone should always be taken with food in order for it to work properly.

If you are using atovaquone in its oral liquid form, it will come in either a bottle or a foil pouch.

If taking atovaquone medication in the foil pouch, you can take 5 mL of the medicine by squeezing the contents of a single pouch directly in your mouth. Alternatively you can squeeze the contents into a dosing cup or spoon. Should your prescription require a 10 mL dose of the medicine, you should take the contents of two entire pouches.

If you are taking oral liquid atovaquone from the bottle, you should gently shake the bottle before using the medication. You should use a marked medicine cup, marked measuring spoon, or marked oral syringe to measure an accurate dose each time, as a regular teaspoon might not hold the correct dose of liquid.

If necessary, you should crush atovaquone tablets to make them easier to swallow.

Atovaquone oral suspension and tablets do not create the same amounts of medication in the bloodstream and, as such, may not be switched and used to replace one another.

You should take your medication for the full term of treatment, in order to clear your infection completely, even if you start feeling better a few days into your course of treatment. If you cease taking your medication too early, the symptoms might return.

Major Drug Interactions

Certain medications should never be utilised together because of the harmful interactions they might have with one another. In some other cases it is appropriate to combine two different medications, even if a known interaction may occur. In such circumstances, your prescribing doctor might wish to amend the dose of one or other of the drugs, or they might insist on other precautions, as necessary. When you are prescribed atovaquone, it is vital that you let your healthcare professional know whether you are currently taking any of the following medicines. These interactions have been chosen based on their potential significance and this list is not necessarily exhaustive.

Using atovaquone with the following medications is not normally recommended, but it might be necessary in certain cases. If both medications are prescribed together, your health care professional might choose to alter the dosage or the frequency of one or more of the medicines:

  • efavirenz
  • rifabutin
  • rifampin

Using atovaquone with the following medications might cause a higher risk of certain side effects, yet the combination of both drugs might be the best treatment for your condition. Should your doctor prescribe both drugs simultaneously, they might choose to change the dosage, or the frequency one or both of the medications:

  • indinavir
  • tetracycline
  • warfarin

Certain medications should not be used while eating certain foods, since unwanted interactions might occur. Likewise, using tobacco products or alcohol with certain drugs might also cause unwanted interactions to occur. You should always discuss how to use your medication alongside food, tobacco, and alcohol with your prescribing doctor.

The presence of certain medical conditions might affect your use of atovaquone. Be sure to tell your doctor should you have any known medical problems, especially the following:

  • liver disease - use atovaquone with caution, as it might make your condition worse.
  • bowel or stomach problems - atovaquone might not work as expected in patients who have these conditions.


When deciding to undergo a course of atovaquone, the risks of taking the drug need to be weighed against what improvements it will bring. This is something you should decide with your doctor. For this medication, you should consider the following:

Inform your doctor if you have had any allergic or otherwise unusual reactions to atovaquone in the past, or to any other medication. You should also tell your prescribing doctor if you suffer from any other allergies, including to dyes, foods, animals, or preservatives.

There have not been any appropriate studies performed on the effect of atovaquone in children under the age of thirteen. Efficacy and safety have yet to be established.

No geriatric-specific concerns have been documented in the use of atovaquone to date.

Animal studies have shown negative effects during pregnancy, but there have been no adequate studies in pregnant women to establish safety or efficacy of the use of atovaquone during pregnancy.

There have been no adequate studies among women to determine the risk to infants when using atovaquone during breastfeeding. It is important to weigh the benefits of using the medication against the possible risks before taking atovaquone during breastfeeding.

If your symptoms fail to improve during the first few days of your course of treatment, or should they become worse, be sure to meet with your prescribing doctor to discuss.


Atovaquone should always be stored at room temperature and in a closed container. Be sure to keep the medication from freezing, and to keep the container away from direct light, heat, and moisture.

Keep atovaquone sealed in its foil pouch until it is time for your regular dosage.

Always keep atovaquone beyond the reach of children.

Should your atovaquone prescription become out of date, or should you no longer require it, you must make sure that you do not keep it. If you need to know how to dispose of any unwanted or outdated atovaquone, ask your prescribing doctor what the best way is to do so.


Atovaquone is a common treatment for pneumocystis jiroveci pneumonia and pneumocystis jiroveci pneumonia (both known as PCP), which are strains of pneumonia that affect patients who suffer from a weak immune system. It has also proven useful in the treatment of patients who are unable to take more conventional medications.

Last Reviewed:
December 24, 2017
Last Updated:
April 04, 2018