The risk of hyperkalemia with spironolactone is greatest in the elderly, in people with renal impairment (e.g., due to chronic kidney disease or diabetic nephropathy), in people taking certain other medications (including ACE inhibitors, angiotensin II receptor blockers, nonsteroidal anti-inflammatory drugs, the antibiotic trimethoprim, and potassium supplements), and at higher dosages of spironolactone.Although spironolactone poses an important risk of hyperkalemia in the elderly, in those with kidney or cardiovascular disease, and/or in those taking medications or supplements which increase circulating potassium levels, a large retrospective study found that the rate of hyperkalemia in young women without such characteristics who had been treated with high doses of spironolactone for dermatological conditions did not differ from that of controls. This was the conclusion of a 2017 hybrid systematic review of studies of spironolactone for acne in women as well, which found that hyperkalemia was rare and was invariably mild and clinically insignificant. These findings suggest that hyperkalemia may not be a significant risk in such individuals, and that routine monitoring of circulating potassium levels may be unnecessary in this population. However, other sources have claimed that hyperkalemia can nonetheless also occur in people with more normal renal function and presumably without such risk factors. Occasional testing on a case-by-case basis in those with known risk factors may be justified. Side effects of spironolactone which may be indicative of hyperkalemia and if persistent could justify serum potassium testing include nausea, fatigue, and particularly muscle weakness.
Some studies have found parasitologic cure (a complete elimination of T. cruzi from the body) in children during the early stage of the chronic phase, but overall failure rate in chronically infected individuals is typically above 80%.Some studies indicate treatment with benznidazole during the chronic phase, even if incapable of producing parasitologic cure because it reduces electrocardiographic changes and delays worsening of the clinical condition of the patient.Benznidazole has proven to be effective in the treatment of reactivated  T. cruzi  infections caused by immunosuppression, such as in people with AIDS or in those under immunosuppressive therapy related to organ transplants. Children
Benznidazole can be used in children, with the same 5–7 mg/kg per day weight-based dosing regimen that is used to treat adult infections. A formulation for children up to two years of age is available. It was added to the WHO Essential Medicines List for Children in 2013. Children are found to be at a lower risk of adverse events compared to adults, possibly due to increased hepatic clearance of the drug. The most prevalent adverse effects in children were found to be gastrointestinal, dermatologic, and neurologic in nature. However, the incidence of severe dermatologic and neurologic adverse events is lower in the pediatric population compared to adults. It use for Chagas in children was approved by the FDA in the US in 2017. Pregnant women
Studies in animals have shown that benznidazole can cross the placenta. Due to its potential for teratogenicity, use of benznidazole in pregnancy is not recommended.