Benznidazole 12.5mg Tablets

Benznidazole is a nitroimidazole derivative that acts as a prodrug. It is reduced by parasite nitroreductases to form reactive metabolites (e.g., nitro radical anions). These metabolites bind covalently to and damage parasite macromolecules (DNA, RNA, proteins, lipids), leading to inhibition of protein and nucleic acid synthesis and ultimately parasite death. It is active against Trypanosoma cruzi.

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. If your child exhibits any of the following symptoms, contact their doctor or seek immediate medical attention:

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
Dizziness or headache
Severe skin reactions, including:
+ Toxic epidermal necrolysis (TEN)
+ Red, swollen, blistered, or peeling skin
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, eyes, genitals, or any areas of skin
+ Fever
+ Chills
+ Body aches
+ Shortness of breath
+ Swollen glands
Nerve problems, such as:
+ Burning
+ Numbness
+ Tingling (note: these symptoms may take several months to resolve after stopping the medication)
Low blood cell counts, which can increase the risk of:
+ Infections
+ Bleeding problems
+ Anemia
+ Signs of infection, such as fever, chills, or sore throat
+ Unexplained bruising or bleeding
+ Feeling very tired or weak

Other Possible Side Effects

Most people experience no side effects or only mild side effects when taking this medication. However, if your child experiences any of the following side effects, contact their doctor or seek medical attention if they are bothersome or persistent:

Stomach pain
Weight loss
Upset stomach or vomiting
* Decreased appetite

Reporting Side Effects

This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your child's doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Your Child Takes This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

If your child is allergic to this medication, any of its components, or any other substances, including foods or drugs. Please describe the allergic reaction and its symptoms.
If your child has Cockayne syndrome, as some individuals with this condition have experienced liver problems, including severe or fatal cases, while taking this medication.
If your child has taken disulfiram in the past 2 weeks.
If your child is breastfeeding, as they should not nurse while taking this medication.

This is not an exhaustive list of potential interactions. Therefore, it is crucial to discuss all of your child's medications (prescription, over-the-counter, natural products, and vitamins) and health conditions with their doctor and pharmacist. Before starting, stopping, or modifying any medication, including this one, ensure that it is safe to do so by consulting with your child's doctor.

It is essential to inform all of your child's healthcare providers, including doctors, nurses, pharmacists, and dentists, that your child is taking this medication. If your child experiences any changes in weight, consult with their doctor, as their dosage may need to be adjusted.

Regular blood work and laboratory tests, as directed by the doctor, are crucial to monitor your child's health while taking this medication. Research has shown that a similar drug has been associated with an increased risk of cancer in mice and rats, although it is unclear if this medication poses a similar risk to humans. If you have concerns, discuss them with your child's doctor.

For children of childbearing age, a pregnancy test is required before initiating this medication to confirm they are not pregnant. Additionally, studies in male rats have shown that this medication may cause temporary fertility problems, which resolved after the medication was discontinued. However, it is unknown if this medication will have a similar effect on human fertility.

If your child is sexually active or may become sexually active, it is crucial to be aware of the potential risks. This medication may harm an unborn baby if taken during pregnancy. To prevent this, your child should use birth control while taking this medication and for a specified period after the last dose, as advised by the doctor. If your child becomes pregnant, contact their doctor immediately.

• Alcohol (disulfiram-like reaction possible, though less common than with metronidazole)
• Drugs that cause peripheral neuropathy (e.g., amiodarone, isoniazid, phenytoin, vincristine) - theoretical additive risk
• Drugs that cause bone marrow suppression (e.g., azathioprine, methotrexate) - theoretical additive risk

• Rash (maculopapular, generalized dermatitis, severe cutaneous reactions)
• Peripheral neuropathy (numbness, tingling, pain, weakness in extremities)
• Gastrointestinal symptoms (abdominal pain, nausea, vomiting, anorexia, diarrhea)
• Fatigue, malaise
• Fever
• Muscle pain (myalgia)
• Joint pain (arthralgia)
• Headache
• Dizziness
• Insomnia
• Anxiety
• Depression
• Bone marrow suppression (unusual bleeding/bruising, signs of infection, persistent fatigue)
• Signs of liver injury (jaundice, dark urine, persistent nausea/vomiting)
• Swelling of face or limbs (angioedema)
• Difficulty breathing (bronchospasm)
• Lymphadenopathy

Benznidazole should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Chagas disease in pregnant women can lead to congenital transmission to the fetus, which can have severe consequences. Treatment decisions should be made in consultation with experts.

Benznidazole is excreted into breast milk. Due to the potential for serious adverse reactions in the breastfed infant, breastfeeding is not recommended during treatment with benznidazole. A decision should be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of the drug to the mother.

Benznidazole is approved for use in pediatric patients 2 years of age and older. Dosing is weight-based. Children may experience similar adverse effects as adults, including rash, peripheral neuropathy, and gastrointestinal disturbances. Close monitoring is essential.

Clinical studies 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. Elderly patients may be more susceptible to peripheral neuropathy.

• Benznidazole is the only FDA-approved drug for Chagas disease in the US. It is crucial for treating this neglected tropical disease.
• Adherence to the full 60-day treatment course is critical for efficacy, despite the high incidence of adverse effects.
• Adverse reactions are common and often lead to dose reduction or discontinuation. Close monitoring and patient education are key to managing these.
• Skin reactions (rash) are very common, especially in the first few weeks. Mild reactions may be managed symptomatically, but severe reactions require discontinuation.
• Peripheral neuropathy is a dose-limiting toxicity and can be irreversible. Patients should be educated to report symptoms promptly.
• Benznidazole is generally more effective in the acute and indeterminate phases of Chagas disease, and in younger patients.
• The 12.5mg tablet strength is specifically designed for pediatric dosing, allowing for more precise weight-based administration.

• Nifurtimox (another nitrofurfural derivative, also approved for Chagas disease)

If your child's symptoms or health issues persist or worsen, it is essential to contact their doctor promptly. To ensure safe use, never share your child's medication with others, and do not administer someone else's medication to your child. For comprehensive information about this medication, consult the patient information leaflet that may accompany it. If you have any questions or concerns, discuss them with your child's doctor, nurse, pharmacist, or other healthcare provider. Additionally, you can check with your pharmacist for any supplementary patient information leaflets. In the event of a suspected overdose, immediately contact your local poison control center or seek urgent medical attention. When reporting the incident, be prepared to provide details about the medication taken, the quantity, and the time it occurred.