# Chagas Disease (American Trypanosomiasis) - Category: chronic - Review status: reviewed (every claim checked against a document named on this page) - Sources: Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/ · ICPC-3 (WONCA International Classification of Primary Care, 3rd edition) class AD24.01 - condition scope only, no dose · Egyptian drug register - availability only, no dose - Verified date: 2026-09 ## Verified against - Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/, Treatment / Management (benznidazole 5-10 mg/kg/day divided q12h for 30-60 days; nifurtimox 8-10 mg/kg/day in 3 doses for 60-120 days) - Egyptian drug register (neither benznidazole nor nifurtimox is marketed) ## Treatment metadata - Benznidazole — 100 mg — oral.solid - Recognition, travel history and referral (Referral & Advice) ## Complete treatment card ```text CHAGAS DISEASE (AMERICAN TRYPANOSOMIASIS) Sources: Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/ · ICPC-3 (WONCA International Classification of Primary Care, 3rd edition) class AD24.01 - condition scope only, no dose · Egyptian drug register - availability only, no dose Review status: REVIEWED against Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/, Treatment / Management (benznidazole 5-10 mg/kg/day divided q12h for 30-60 days; nifurtimox 8-10 mg/kg/day in 3 doses for 60-120 days), Egyptian drug register (neither benznidazole nor nifurtimox is marketed) (2026-09) IS IT THIS? - reference only, to read alongside your own examination SYMPTOMS - what the patient reports (6) - Patients rarely recall or mention the triatomine bug bite itself - Acute illness often brings fever, localized swelling, enlarged lymph nodes, muscle aches, pallor, breathlessness and abdominal or chest pain [abdominal pain · breathlessness · chest pain · fever · lymphadenopathy · muscle pain · pallor] - A minority develop an anaphylactic-type reaction to the bite, with hives, flushing, wheeze, nausea, vomiting and diarrhea [diarrhoea · nausea · urticaria · vomiting · wheeze] - Congenital transmission can cause prematurity, low birth weight, fever, anemia and reduced muscle tone [anaemia · fever] - Chronic cardiac disease can present with fever, an enlarged heart, apical aneurysms, ECG changes, or frank heart failure [fever] - Chronic GI-phase Chagas can present with fever, megaesophagus, megacolon and constipation [constipation · fever] SIGNS - what you find (5) - One-sided conjunctivitis with purplish eyelid swelling, called Romana sign or a chagoma, is a hallmark finding [eyelid swelling] - Cardiomegaly can show up as a displaced apical impulse, narrowed pulse pressure or sinus tachycardia [tachycardia] - Right heart failure can bring bibasilar lung crackles and pitting swelling of both legs [crackles] - The abdomen can be distended but soft, with quiet bowel sounds, and rectal exam may find impacted stool - Exam may find an enlarged liver and spleen plus conjunctival pallor from chronic anemia [anaemia · hepatomegaly · pallor] TESTS (7) - Acute diagnosis relies on seeing the parasite by microscopy in fresh anticoagulated blood or buffy coat - PCR can turn positive days to weeks before a routine blood smear picks up circulating parasites - ECG, chest x-ray and echocardiography can all show cardiomegaly, and echo can reveal a reduced ejection fraction - ECG often shows first-degree AV block and atrial flutter or fibrillation, plus conduction defects such as right bundle branch block or left anterior fascicular block - Abdominal x-rays can show bowel pseudo-obstruction or an enlarged megacolon - Barium swallow or enema studies can be used to further evaluate GI symptoms - Chronic infection is confirmed by finding IgG antibodies against T. cruzi IF NOT THIS - what else fits (11) - Esophageal motility disorders belong on the differential list - Esophageal rupture belongs on the differential list - Esophageal spasm belongs on the differential list - Esophagitis belongs on the differential list - Gastroesophageal reflux disease belongs on the differential list - Leishmaniasis belongs on the differential list - Malaria belongs on the differential list - Meningitis belongs on the differential list - Myocardial infarction belongs on the differential list - Myocardial rupture belongs on the differential list - Congestive heart failure belongs on the differential list Source StatPearls "Chagas Disease" - disease-level clinical article Status traced to the source above Rx: Antitrypanosomal treatment - specialist-sourced | Recognition and referral ANTITRYPANOSOMAL TREATMENT - SPECIALIST-SOURCED 1. BENZNIDAZOLE [1st line] Adult 5 to 10 mg/kg/day divided every 12 hours for 30 to 60 days. NOT MARKETED IN EGYPT - obtained through a tropical medicine centre x 30-60 days Peds 5-10 mg/kg/day (Divided every 12 hours, for 30 to 60 days. The article gives one weight-based regimen and says only that "Pediatric dosing also includes a 60-day weight-based regimen" without stating separate figures, so the same mg/kg/day range is shown here and no different paediatric number is invented. Treatment is most effective in children and in acute infection, which is why a child is the patient most likely to be treated.) 3kg -> 15-30 mg/day 4kg -> 20-40 mg/day 5kg -> 25-50 mg/day 6kg -> 30-60 mg/day 7kg -> 35-70 mg/day 8kg -> 40-80 mg/day 9kg -> 45-90 mg/day 10kg -> 50-100 mg/day 11kg -> 55-110 mg/day 12kg -> 60-120 mg/day 13kg -> 65-130 mg/day 14kg -> 70-140 mg/day 15kg -> 75-150 mg/day 16kg -> 80-160 mg/day 17kg -> 85-170 mg/day 18kg -> 90-180 mg/day 19kg -> 95-190 mg/day 20kg -> 100-200 mg/day 21kg -> 105-210 mg/day 22kg -> 110-220 mg/day 23kg -> 115-230 mg/day 24kg -> 120-240 mg/day 25kg -> 125-250 mg/day 26kg -> 130-260 mg/day 27kg -> 135-270 mg/day 28kg -> 140-280 mg/day 29kg -> 145-290 mg/day 30kg -> 150-300 mg/day 31kg -> 155-310 mg/day 32kg -> 160-320 mg/day 33kg -> 165-330 mg/day 34kg -> 170-340 mg/day 35kg -> 175-350 mg/day 36kg -> 180-360 mg/day 37kg -> 185-370 mg/day 38kg -> 190-380 mg/day 39kg -> 195-390 mg/day 40kg -> 200-400 mg/day 41kg -> 205-410 mg/day 42kg -> 210-420 mg/day 43kg -> 215-430 mg/day 44kg -> 220-440 mg/day 45kg -> 225-450 mg/day 46kg -> 230-460 mg/day 47kg -> 235-470 mg/day 48kg -> 240-480 mg/day 49kg -> 245-490 mg/day 50kg -> 250-500 mg/day Choice The alternative, with its dose, from the same article: "Nifurtimox is the other antitrypanosomal therapy but is not currently FDA-approved. However, nifurtimox can be obtained through the Centers for Disease Control and Prevention (CDC) under an investigational protocol. Dosing is 8 to 10 mg/kg/day divided into 3 doses for 60 to 120 days." Gastrointestinal effects are very common with it, and the more serious ones include neurotoxicity. A longer course, three times a day, harder to obtain, and no evidence that it works better - which is why benznidazole leads. Source Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/, Treatment / Management - verbatim: "Benznidazole was approved by the Food and Drug Administration (FDA) in 2017 with a recommended dosage of 5 to 10 mg/kg/day divided every 12 hours for 30 to 60 days." Availability from the Egyptian drug register Why Antitrypanosomal. There are only two drugs for this infection and neither is clearly better: the article, citing the Pan American Health Organization guideline, records that "evidence to suggest which medication should be used as the first-line option is lacking; however, in the United States, benznidazole is used more often due to availability." Benznidazole leads here for the same reason - it is the one that is FDA- approved and can be obtained, whereas nifurtimox cannot. Caution NOT MARKETED IN EGYPT. Neither benznidazole nor nifurtimox has any entry in the national drug register, so treatment cannot be started from a Cairo prescription. A suspected case is referred to a tropical medicine centre, which is also where the drug is sourced. The dose is printed here so the referring physician knows what is being arranged. RED FLAG - Two adverse effects are a reason to stop the drug at once, not to reduce it. The article: "A common adverse effect is dermatitis; more serious adverse effects include myelosuppression and peripheral neuropathy" and "The presence of myelosuppression or neuropathy is an indication to discontinue treatment immediately." That means a blood count and a neurological enquiry at every review during a course this long. The course is long and completion matters. Thirty to sixty days of twice-daily treatment with a drug that commonly causes a rash is hard to finish; the rash is the usual reason people stop. Warn about it in advance and review early. Not a Cairo diagnosis without a travel history. The triatomine ('kissing') bug that transmits it lives only in the Americas, so this is relevant to someone who lived in or travelled extensively through Latin America. Consider the travel history before anything else. Egypt no Egyptian brand matched - prescribe by generic name RECOGNITION AND REFERRAL 2. RECOGNITION, TRAVEL HISTORY AND REFERRAL (REFERRAL & ADVICE)[2nd line] Adult Chronic protozoal infection spread by triatomine ('kissing') bugs found only in the Americas. Not a Cairo diagnosis except in someone who lived in or travelled extensively through Latin America; the specific drugs (benznidazole, nifurtimox) are not marketed in Egypt, so any suspected case needs referral to a tropical medicine centre. - Refer Peds Children follow the same pathway: recognise and refer. No primary-care medicine is implied. Source No dose - the recognition and referral pathway, from Chagas Disease - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK459272/, Treatment / Management Why Chronic protozoal infection spread by triatomine ('kissing') bugs found only in the Americas. Not a Cairo diagnosis except in someone who lived in or travelled extensively through Latin America; the specific drugs (benznidazole, nifurtimox) are not marketed in Egypt, so any suspected case needs referral to a tropical medicine centre. Caution Not endemic in Egypt. Relevant to a returning traveller or an imported case; consider the travel history before anything else. The drug row above carries the dose that the receiving centre will use. RED FLAG - An acute febrile illness with periorbital swelling (Romana's sign) after a relevant exposure, or unexplained cardiomyopathy, megacolon or megaoesophagus in someone from an endemic area. The chronic complications are what usually bring the patient in, years later. Treatment is decided by a tropical medicine service, not started here - but the diagnosis is missed in primary care, which is where it matters. Both drugs work best in acute infection and in children, so recognising it early changes the outcome. Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy. ``` --- Dawaa Reference is a reference for prescribers, not a medical device, and does not replace clinical judgement. [Privacy policy](/privacy)