Atovaquone and Proguanil

This medicine is a combination of atovaquone and proguanil marketed under the brand name Malarone that is used to treat the red blood cell infection Malaria, which is typically transmitted from host to host by biting insects.

Overview

Atovaquone-proguanil is a combination oral medication that combines two drugs, atovaquone and proguanil, into a single tablet. This prescription-only medication is marketed and sold under the brand name Malarone and is available in both adult strength and a separate medication intended for pediatric use. Atovaquone-proguanil can be prescribed by a doctor either for the purpose of preventing potential malaria infection or used to treat an ongoing infection. It is often prescribed to be taken before traveling to locations with an ongoing malaria outbreak or where insects known to carry the disease are common.

The active ingredients in Malarone, atovaquone & proguanil, treat the patient by blocking pathways involved in the biosynthesis of pyrimidines required for nucleic acid replication, preventing a malarial infection from growing. This action inhibits parasite mitochondrial electron transport, naturally aiding the body's efforts to kill the infected cells and resists any further infection of the red blood cells. This is a very strong pharmaceutical treatment that can have significant side effects and adverse reactions with other medications, but - given the life-threatening nature of malaria infection - it is a common treatment option.

Conditions treated:

  • Malaria

Type of Medication:

  • Ubiquinone/Biguanide Combination

Side Effects:

Along with the intended antimalarial effects of an Atovaquone and Proguanil regimen, there can be unwanted side effects. Not all of these effects will necessarily occur for every patient, but some that do are quite serious and may require immediate medical attention. If there is any indication that you are experiencing the following side effects inform your medical provider as quickly as possible.

Patients using Atovaquone and Proguanil can experience some of the following skin problems while using this medication:

  • Blistering, peeling, loosening of skin
  • Hives or welts
  • Increased sensitivity of skin to sunlight
  • Itching, redness or other discoloration of skin
  • Puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • Skin rash
  • Sores, ulcers or white spots in mouth or on lips
  • Severe sunburn
  • Red skin lesions, often with a purple center
  • Large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, sex organs

Those taking Atovaquone and Proguanil have also noted the following side-effects on internal organs

  • Difficulty swallowing
  • Fast heartbeat
  • Loss of bladder control
  • Red, irritated eyes
  • Shortness of breath
  • Tightness in chest
  • Wheezing

There have also been reports of the following muscular-skeletal problems while using Atovaquone and Proguanil

  • Chills
  • Convulsions
  • Joint or muscle pain
  • Muscle spasm or jerking of all extremities

Additionally, Atovaquone and Proguanil can have the following mental side effects

  • Seeing, hearing, or feeling things that are not there
  • Severe mental changes
  • Sudden loss of consciousness
  • Unusual tiredness or weakness

All of the above side effects could be a precursor to a more serious health problem and need treatment by a physician immediately upon experiencing them. However, there are some side effects that do not require prompt medical attention and may subside without treatment. Often, these side effects are a result of the body adjusting to taking the medication and will go away on their own once this period of adjustment is complete. Your doctor or health care professional will have more information on known side effects and methods to deal with them. They may have additional treatments or recommend over the counter medications to make these side effects less severe and easier to deal with. If any of these side effects continue beyond an acceptable duration or are more severe, you should not hesitate to contact your primary care provider with any questions.

Less concerning side effects noted during use of Atovaquone and Proguanil include the following symptoms and conditions.

Cold or flu-like symptoms

  • Coughing
  • Fever
  • Nausea
  • Vomiting
  • Stomach discomfort, upset or pain
  • Sneezing
  • Sore throat

Skin Conditions

  • Itching skin
  • Sores in mouth

Eyesight conditions

  • Blurred or loss of vision
  • Tunnel vision
  • Light blindness
  • Overbright appearance of lights
  • Disturbed color perception
  • Double vision
  • Halos around lights

Muscular-skeletal Conditions:

  • Back pain
  • Headache
  • Lack of or loss of strength
  • Muscle pain

Mental conditions:

  • Bad dreams
  • Dizziness
  • Sleeplessness
  • Trouble sleeping
  • Unable to sleep
  • Discouragement
  • Fear
  • Feeling sad or empty
  • Irritability
  • Nervousness
  • Trouble concentrating
  • Loss of interest or pleasure

Organ or Internal Conditions

  • Abdominal pain
  • Diarrhea
  • Acid or sour stomach
  • Belching
  • Heartburn
  • Indigestion
  • Loss of appetite
  • Weight loss
  • Lack of appetite

Side effects other than the ones listed may occur in some individuals. If you notice any other symptoms bring them to the attention of a medical professional as they may indicate a more serious condition.

Dosage:

The dose of Atovaquone and Proguanil required may vary by patient depending upon the severity of their condition. Follow all directions from your doctor in regards to this. The following dosage information includes only the average or recommended dosage guidelines for this medicine from the manufacturer. If you are prescribed a dosage different than this, do not make any effort to change your dose without the express permission of the prescribing physician. The amount of your particular dose depends upon many factors including the strength of the medicine, the duration of the treatment, number of doses per day, and your general medical condition. It may also vary based on the allowed time between doses, as well as any other medications that you are taking at the same time.

The guidelines for oral dosage of Atovaquone and Proguanil (Malarone) are as follows:

Adult dose for prevention: 250 milligrams (mg) of atovaquone and 100 mg proguanil (one adult strength tablet) per day starting one to two days before entering a malarial area and continuing for seven days following return.

Pediatric Dose: The Recommended dosage for children varies by age and weight of the child, and for children weighing 25 pounds or less will be determined by the pediatric physician. this will range from one to three pediatric tablets per day determined by weight and age. For children over 40 pounds, the adult dosage is used.

For treatment of acute malaria the dosage recommendations are as follows:

Adults: 1 gram of atovaquone and 400 mg of proguanil (4 adult strength tablets) once daily as a single dose is taken for three days in a row.

Children: Dosage at the discretion of the prescribing physician.

In the event that you miss a dose of this medication, you should take it as soon as possible after the missed dose. However, if it is almost time for the next dose you should forgo the dose in favor of the upcoming dose. In no circumstances should you double dosage, but rather take the following dose to get back on the regular dosing schedule. If you have any questions or concerns regarding this, please contact your physician or pharmacist.

Interactions:

Atovaquone and Proguanil have documented interactions with over 112 other medications that vary widely in degree of severity. These interactions can impact how well the medications work for your condition or increase risks of serious side effects known to occur in both medications. While this is not a comprehensive list of all possible drug interactions that are possible, it is important to be aware of these most severe drug interactions. It is very important that you keep a comprehensive list of all medications that are being taken, whether prescription or nonprescription and share it with your prescribing physician. Do not start, stop, or change dosages of any medicine without the prior approval of your doctor as this can result in more serious health conditions than the potential drug interactions.

Some common pharmaceutical treatments that are known to interact with Atovaquone and Proguanil include the following products:

  • Penicillamine
  • Warfarin and other blood thinners
  • Metoclopramide.

Some medications have been known to cause a complication that makes it difficult for atovaquone/proguanil to naturally leave your system, affecting how the medication works. These include:

  • Efavirenz
  • Rifampin
  • Tetracycline
  • Rifabutin

Food Interactions: Food that is high in fat content can significantly enhance the oral absorption of the atovaquone in this medication, resulting in as much as a 2.5-fold increase in concentration in the plasma. In order to maximize oral absorption of the medication, it is recommended that the medication is administered with milk or food. For patients with a condition that would make it difficult to take the medication with a meal, alternative therapies are recommended.

There are many other medications with documented interactions with Atovaquone and Proguanil and the above are only some of the most severe. If you have any concern that a medication, supplement, or herbal remedy that you are currently using may have an adverse reaction with your Atovaquone and Proguanil regimen, please discuss this with your doctor prior to taking the medicine.

Warnings:

If you are living in or plan on traveling to an area where malaria transmission is possible, Atovaquone and Proguanil is only one precautionary measure that you can take. Malaria primarily transmitted by the bites of infected female mosquitos. There are certain mosquito control steps that can be taken to significantly lower the chances of malarial infection. This includes remaining in air-conditioned or well-screened rooms to reduce contact with the insects. Sleeping underneath a mosquito netting or using permethrin or DEET as a repellant can also be effective. Wearing long-sleeved shirts and long trousers to protect legs and arms during the active times of mosquitos (dusk through dawn) is also recommended. Combining these precautions with a dose of Atovaquone and Proguanil is your best chance of avoiding a potentially deadly bout of malaria.

You should contact your doctor immediately if you have any of the following symptoms while taking Atovaquone and Proguanil as they can be indicative that you are having an allergic reaction to the medication.

  • Cough,
  • Difficulty swallowing
  • Dizziness
  • Fast heartbeat
  • Hives
  • Itching
  • Puffiness or swelling of the eyelids or around the eyes, face, lips or tongue
  • Shortness of breath
  • Skin rash
  • Tightness in the chest
  • Unusual tiredness or weakness
  • Wheezing

One of the most well-known adverse reactions associated with Atovaquone and proguanil is that it may cause your skin to be far more sensitive to sunlight than is normally the case. Be sure to wear protective clothing such as hats or use skincare products to prevent sunburn before spending any time in direct sunlight.

Atovaquone can be less effective under fasting conditions and is much more effective when taken with food. Patients with gastrointestinal disorders or eating disorders may be more likely to be unable to maximize the benefit of this medication and leave themselves vulnerable to potential malarial infection. Alterations to treatment or alternative therapies may be necessary in order to protect these patients from malarial infection at an acceptable level.

If you are suffering from any kind of liver disease you should have regular liver function tests while taking Atovaquone and if any significant elevations of serum alkaline phosphatase concentrations are noted your doctor may withdraw this therapy for health reasons. For all patients with a liver condition or hepatitis, this medication should only be administered with extreme caution.

Storage:

Atovaquone and Proguanil should be stored in a closed container at room temperature in a secure location out of the reach of children. It should be kept away from both intense heat and cold and be prevented from freezing. If the medication is no longer needed please dispose of it in adherence to guidelines regarding the disposition of medical waste.

Summary

While Atovaquone and Proguanil is an extremely beneficial and potentially lifesaving drug, it is a very strong medication with severe documented side effects that should not be taken as the only precaution against a potential malarial infection. It is a preventative and acute treatment, but it is only part of a treatment plan intended to maximize your immune system against possible infection by an extremely aggressive and potentially fatal disease. Be very aware that some of the side effects of taking Atovaquone and Proguanil can result in terrifying mental conditions and extreme impairment that may make everyday actions such as driving and operating machinery much more dangerous than they would normally be. This medication should only be taken under the direct prescription by a physician based on your current state of health and not be taken just because you took it in the past when traveling into potential malarial zones.

Despite various troubling side-effects and potential drug interactions, this medication is one that doctors depend on to combat malaria. When used as directed, the combination Atovaquone and Proguanil oral medication can be a very effective part of a comprehensive malaria prevention strategy. However, taking it is not a substitution for other risk-prevention measures such as avoiding contact with infected insects, application of insect repellants, or seeking shelter during stays in malarial outbreak zones. Remember that when visiting these areas you should follow all CDC guidelines and precautions that are recommended based on the environment of the area.

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Last Reviewed:
December 24, 2017
Last Updated:
February 09, 2018