Mepron 750mg/5ml Suspension
It is used to treat or prevent infections caused by Pneumocystis jirovecii.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antiprotozoal
Pharmacologic Class
Hydroxynaphthoquinone
Pregnancy Category
Category C
FDA Approved
Dec 1992
DEA Schedule
Not Controlled
Overview
What is this medicine?
Mepron is a liquid medicine used to treat or prevent a serious lung infection called Pneumocystis pneumonia (PCP), which often affects people with weakened immune systems. It works by stopping the growth of the germs that cause this infection. It's very important to take this medicine with food, especially a fatty meal, to help your body absorb it properly.
How to Use This Medicine
Taking Your Medication Correctly
To ensure you get the most benefit from your medication, follow these steps:
Always take your medication as directed by your doctor and follow the instructions provided with your prescription.
Before using your medication, shake the container well.
Take your medication with food to help your body absorb it properly. If you have trouble taking it with food, consult your doctor for guidance.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Using Your Medication
Depending on the form of your medication, follow these instructions:
Unit-dose: Open the pouch and take the contents by mouth. You can place it directly in your mouth, in a dosing spoon, or in a cup.
Bottle: Measure your liquid dose carefully using the measuring device provided with your medication. If one is not included, ask your pharmacist for a suitable measuring device.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication:
Store it at room temperature, avoiding freezing.
Keep it in a dry place, away from bathrooms.
Store all medications in a secure location, out of the reach of children and pets.
What to Do If You Miss a Dose
If you miss a dose, follow these steps:
Take the missed dose as soon as you remember, with food.
If it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed one.
To ensure you get the most benefit from your medication, follow these steps:
Always take your medication as directed by your doctor and follow the instructions provided with your prescription.
Before using your medication, shake the container well.
Take your medication with food to help your body absorb it properly. If you have trouble taking it with food, consult your doctor for guidance.
Continue taking your medication as prescribed by your doctor or healthcare provider, even if you start to feel better.
Using Your Medication
Depending on the form of your medication, follow these instructions:
Unit-dose: Open the pouch and take the contents by mouth. You can place it directly in your mouth, in a dosing spoon, or in a cup.
Bottle: Measure your liquid dose carefully using the measuring device provided with your medication. If one is not included, ask your pharmacist for a suitable measuring device.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication:
Store it at room temperature, avoiding freezing.
Keep it in a dry place, away from bathrooms.
Store all medications in a secure location, out of the reach of children and pets.
What to Do If You Miss a Dose
If you miss a dose, follow these steps:
Take the missed dose as soon as you remember, with food.
If it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule.
Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Always take Mepron with food, preferably a high-fat meal (e.g., milk, peanut butter, cheese, fatty meat) to ensure proper absorption. If you cannot eat, discuss alternatives with your doctor.
- Shake the bottle well before each use.
- Use the provided measuring spoon or cup to ensure accurate dosing.
- Do not miss doses. If you miss a dose, take it as soon as you remember with food. If it's almost time for your next dose, skip the missed dose and continue your regular schedule. Do not double dose.
- Store at room temperature, away from light and moisture.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Pneumocystis Pneumonia (PCP) Treatment: 750 mg (5 mL) orally twice daily with food for 21 days. PCP Prophylaxis: 1500 mg (10 mL) orally once daily with food.
Dose Range:
750 - 1500 mg
Condition-Specific Dosing:
PCP Treatment:
750 mg (5 mL) orally twice daily with food for 21 days
PCP Prophylaxis:
1500 mg (10 mL) orally once daily with food
Pediatric Dosing
Neonatal:
Not established
Infant:
PCP Treatment (1-3 months): 30 mg/kg orally twice daily with food for 21 days (max 750 mg/dose). PCP Prophylaxis (1-3 months): 30 mg/kg orally once daily with food (max 1500 mg/day).
Child:
PCP Treatment (4 months-12 years): 30 mg/kg orally twice daily with food for 21 days (max 750 mg/dose). PCP Prophylaxis (4 months-12 years): 30 mg/kg orally once daily with food (max 1500 mg/day).
Adolescent:
PCP Treatment (>12 years): 750 mg (5 mL) orally twice daily with food for 21 days. PCP Prophylaxis (>12 years): 1500 mg (10 mL) orally once daily with food.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment necessary.
Moderate:
No adjustment necessary.
Severe:
No adjustment necessary.
Dialysis:
Not significantly removed by dialysis; no adjustment necessary.
Hepatic Impairment:
Mild:
No specific adjustment recommended.
Moderate:
Use with caution; monitor for adverse effects.
Severe:
Use with caution; monitor for adverse effects. Data limited.
Pharmacology
Mechanism of Action
Atovaquone is a hydroxynaphthoquinone that inhibits the electron transport chain in protozoa and fungi, specifically targeting the cytochrome bc1 complex (complex III) in the mitochondrial respiratory chain. This disrupts ATP synthesis and pyrimidine biosynthesis, leading to inhibition of nucleic acid synthesis and ultimately cell death.
Pharmacokinetics
Absorption:
Bioavailability:
Highly variable (21-47% in adults, significantly increased with food)
Tmax:
1-8 hours (with food)
FoodEffect:
Absorption is significantly increased (2-3 fold) when taken with a high-fat meal. Administration without food can result in subtherapeutic plasma concentrations.
Distribution:
Vd:
0.6 L/kg
ProteinBinding:
>99.9% (primarily to albumin)
CnssPenetration:
Limited (CSF concentrations are <1% of plasma concentrations)
Elimination:
HalfLife:
53-75 hours (adults); 30-40 hours (children)
Clearance:
Not readily quantifiable due to minimal metabolism and high protein binding.
ExcretionRoute:
Primarily fecal excretion (>94% as unchanged drug)
Unchanged:
>94%
Pharmacodynamics
OnsetOfAction:
Not precisely defined for clinical effect; therapeutic levels achieved within days with consistent dosing.
PeakEffect:
Not precisely defined for clinical effect.
DurationOfAction:
Due to long half-life, effects persist for several days after discontinuation.
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. Immediately contact your doctor or seek medical attention if you experience any of the following symptoms:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Depression
Fever
White patches in the mouth
Cough
Liver problems, which can be rare but potentially deadly. Be aware of signs such as:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they bother you or persist:
Headache
Diarrhea
Upset stomach or vomiting
Muscle pain
Trouble sleeping
Excessive sweating
Runny or stuffy nose
Flu-like symptoms
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. Immediately contact your doctor or seek medical attention if you experience any of the following symptoms:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Depression
Fever
White patches in the mouth
Cough
Liver problems, which can be rare but potentially deadly. Be aware of signs such as:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they bother you or persist:
Headache
Diarrhea
Upset stomach or vomiting
Muscle pain
Trouble sleeping
Excessive sweating
Runny or stuffy nose
Flu-like symptoms
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe skin rash or allergic reaction (hives, difficulty breathing, swelling of face/lips/tongue/throat)
- Persistent nausea, vomiting, or diarrhea (especially if severe and leading to dehydration)
- Unusual bleeding or bruising (if on warfarin)
- Yellowing of the skin or eyes (jaundice)
- Dark urine
- Severe headache
- Unexplained fever or chills
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking rifabutin or rifampin, as these medications may interact with this drug.
This list is not exhaustive, and it is crucial to disclose all your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
* Vitamins
Additionally, inform your doctor about any existing health problems. This information will help your doctor determine whether it is safe for you to take this medication in conjunction with your other medications and health conditions.
Remember, do not start, stop, or adjust the dosage of any medication without first consulting your doctor to ensure your safety.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you are currently taking rifabutin or rifampin, as these medications may interact with this drug.
This list is not exhaustive, and it is crucial to disclose all your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
* Vitamins
Additionally, inform your doctor about any existing health problems. This information will help your doctor determine whether it is safe for you to take this medication in conjunction with your other medications and health conditions.
Remember, do not start, stop, or adjust the dosage of any medication without first consulting your doctor to ensure your safety.
Precautions & Cautions
It is essential to inform all of your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you are pregnant, planning to become pregnant, or are currently breast-feeding, be sure to discuss this with your doctor. This conversation will help you understand the potential benefits and risks of taking this medication during pregnancy or breast-feeding, allowing you to make an informed decision about your care and the well-being of your baby.
Overdose Information
Overdose Symptoms:
- Exaggerated side effects such as severe nausea, vomiting, diarrhea, rash, or headache.
What to Do:
There is no specific antidote for atovaquone overdose. Treatment should be symptomatic and supportive. Contact a poison control center immediately (Call 1-800-222-1222 in the US).
Drug Interactions
Major Interactions
- Rifampin
- Rifabutin
- Tetracycline
- Metoclopramide
Moderate Interactions
- Warfarin
- Indinavir
- Efavirenz
- Ritonavir
- Lopinavir/Ritonavir
- Tipranavir/Ritonavir
Confidence Interactions
Monitoring
Baseline Monitoring
Baseline clinical assessment of symptoms (e.g., respiratory status for PCP)
Rationale: To establish a baseline for evaluating treatment efficacy.
Timing: Prior to initiation of therapy
Liver function tests (ALT, AST, bilirubin)
Rationale: Although not extensively metabolized, caution in severe hepatic impairment is advised.
Timing: Prior to initiation of therapy (especially if pre-existing hepatic dysfunction)
Renal function (SCr, BUN)
Rationale: To assess baseline kidney function, though no dose adjustment is needed for renal impairment.
Timing: Prior to initiation of therapy
Routine Monitoring
Clinical response to therapy (e.g., improvement in respiratory symptoms for PCP)
Frequency: Daily/as clinically indicated
Target: Resolution of symptoms
Action Threshold: Lack of improvement or worsening symptoms may indicate treatment failure or alternative diagnosis.
Adverse effects (e.g., rash, GI upset, headache)
Frequency: Daily/as clinically indicated
Target: Absence or mild, tolerable side effects
Action Threshold: Severe or persistent adverse effects may require dose adjustment or discontinuation.
INR (if on warfarin)
Frequency: More frequently (e.g., 2-3 times per week initially)
Target: Therapeutic range for indication
Action Threshold: INR outside target range; adjust warfarin dose as needed.
Symptom Monitoring
- Rash
- Nausea
- Vomiting
- Diarrhea
- Abdominal pain
- Headache
- Fever
- Cough
- Shortness of breath
- Fatigue
- Yellowing of skin or eyes (jaundice)
- Dark urine
Special Patient Groups
Pregnancy
Atovaquone is Pregnancy Category C. Animal studies have shown adverse effects on the fetus, but there are no adequate and well-controlled studies in pregnant women. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential for developmental toxicity observed in animal studies; human data limited.
Second Trimester:
Human data limited; consider risk vs. benefit.
Third Trimester:
Human data limited; consider risk vs. benefit.
Lactation
Atovaquone is excreted into breast milk in animals. It is unknown whether it is excreted in human milk. Due to the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. Lactation risk is L3 (moderately safe).
Infant Risk:
Potential for adverse effects in nursing infant; monitor for diarrhea, rash, or other signs of toxicity. Long half-life may lead to accumulation.
Pediatric Use
Dosing is weight-based for children. Safety and efficacy have been established for PCP treatment and prophylaxis in children aged 1 month and older. Absorption can be more variable in very young infants, emphasizing the importance of administration with food.
Geriatric Use
Clinical studies of Mepron did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Clinical Information
Clinical Pearls
- Always emphasize taking Mepron with a high-fat meal to maximize absorption and ensure therapeutic levels. Failure to do so is a common cause of treatment failure.
- The suspension must be shaken well before each use.
- Mepron has a long half-life, which allows for once or twice daily dosing, but also means it takes time to reach steady state and clear from the body.
- Monitor for drug interactions, especially with rifamycins and metoclopramide, which can significantly reduce atovaquone levels.
- While not renally cleared, ensure adequate hydration, especially in patients with GI side effects.
Alternative Therapies
- Trimethoprim/Sulfamethoxazole (TMP/SMX - first-line for PCP treatment and prophylaxis)
- Pentamidine (IV or inhaled - alternative for PCP treatment/prophylaxis)
- Dapsone (for PCP prophylaxis)
- Clindamycin + Primaquine (for PCP treatment)
Cost & Coverage
Average Cost:
Varies widely, typically $1000-$3000+ per 210 mL bottle (750 mg/5 mL)
Generic Available:
Yes
Insurance Coverage:
Tier 2 or 3 (Brand), Tier 1 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication, including the amount taken and the time it happened, to facilitate prompt and effective treatment.