- Diethylcarbamazine (DEC) is the primary treatment for lymphatic filariasis because it is highly effective at both killing microfilariae and adult worms, thereby reducing microfilaremia and transmission.
- DEC directly targets the filarial parasites Wuchereria bancrofti and Brugia malayi, which are the main causative agents.
- Its use leads to significant clinical improvement by decreasing lymphatic inflammation and preventing progression to chronic complications.
- Other agents like ivermectin mainly clear microfilariae but have less effect on adult worms, while doxycycline targets Wolbachia endosymbionts but is still considered adjunctive therapy.
- Therefore, DEC remains the first-line, specific anti-filarial agent for treatment.

Reference: Davidson’s Principles and Practice of Medicine, 24th Edition, Chapter: Tropical Medicine, Page 1194.