Treatment of Paragonimiasis
Praziquantel is the treatment of choice for paragonimiasis, with expert advice recommended regarding adjunctive therapies including corticosteroids to prevent pulmonary fibrosis. 1
Primary Treatment Regimen
Praziquantel is the definitive antiparasitic treatment for paragonimiasis, though the most recent UK guidelines (2025) recommend seeking expert advice rather than specifying exact dosing. 1 Research evidence supports praziquantel 75 mg/kg/day divided into three doses daily for 2 consecutive days as the standard regimen. 2, 3, 4
Alternative Dosing Options
- Triclabendazole has demonstrated comparable or superior efficacy to praziquantel with better tolerability in clinical trials, administered as 10 mg/kg twice in one day or 5 mg/kg once daily for 3 days. 5
- Triclabendazole showed more rapid parasitological clearance and fewer adverse effects compared to praziquantel in head-to-head trials. 5
Adjunctive Therapies
Corticosteroids should be considered as adjunctive therapy based on expert opinion, with the goal of preventing establishment of pulmonary fibrosis. 1 This recommendation parallels the approach used in neuroschistosomiasis where corticosteroids prevent inflammatory complications. 1
Additional Supportive Measures
- Bronchodilators may be responsive for dyspnea symptoms (expert opinion). 1
- Ongoing management by a respiratory physician may be helpful for chronic pulmonary complications. 1
Theoretical Adjuncts Requiring Expert Consultation
The 2025 UK guidelines mention doxycycline and diethylcarbamazine as having theoretical benefit, but emphasize seeking expert advice before use due to potential complications. 1 Diethylcarbamazine carries significant risks in patients co-infected with onchocerciasis, including blindness, hypotension, and severe skin reactions. 1
Treatment Monitoring and Follow-up
- Parasitological cure should be documented by sputum or stool microscopy becoming ova-negative, typically by day 90 post-treatment. 2
- Relapses may occur, necessitating follow-up evaluation. 1
- If standard dosing fails, extending treatment duration (e.g., spreading the same total dose over 4 days) may be considered, though this showed inferior results in one study. 2
Common Pitfalls and Adverse Effects
Adverse reactions to praziquantel include nausea (common), headache, and urticaria, with urticaria potentially secondary to antigen release from drug-damaged parasites. 2 These effects are generally mild and self-limited. 2
Misdiagnosis as tuberculosis is extremely common given the overlapping clinical presentation of chronic cough, hemoptysis, and chest radiograph abnormalities. 1, 6, 3, 4 Clinicians must maintain high suspicion in patients with appropriate dietary exposure history (raw freshwater crabs, crayfish, or wild boar meat). 1, 3, 4
When to Seek Specialist Input
Given the complexity of treatment decisions, particularly regarding corticosteroid use and potential co-infections, specialist parasitology or tropical medicine consultation is strongly recommended before initiating therapy. 1 This is especially critical when considering diethylcarbamazine or managing patients from regions where onchocerciasis is co-endemic. 1