From the Guidelines
The most effective treatment for filariasis is diethylcarbamazine (DEC) 6 mg/kg in 3 divided doses for 14 days, combined with doxycycline 200 mg daily for 6 weeks, as recommended by the latest guidelines 1. This treatment approach is based on the most recent evidence from the UK guidelines for the investigation and management of eosinophilia in returning travelers and migrants, published in the Journal of Infection in 2025 1. The guidelines emphasize the importance of specialist input and excluding co-infections such as onchocerciasis and loiasis before initiating treatment. Key aspects of the treatment include:
- Diethylcarbamazine (DEC) as the primary antiparasitic medication
- Combination with doxycycline to enhance efficacy
- Duration of treatment: 14 days for DEC and 6 weeks for doxycycline
- Importance of specialist input and consideration of co-infections The treatment aims to kill the microfilariae and adult worms, reducing the risk of chronic complications such as lymphedema and elephantiasis. It is essential to note that the treatment may vary depending on the specific type of filariasis and co-infections, highlighting the need for specialist input and careful diagnosis 1.
From the Research
Treatment Options for Filariasis
- The treatment of filariasis has been discussed mainly within the framework of mass drug administration with diethylcarbamazine, ivermectin, and albendazole 2.
- Chemotherapy against filarial Wolbachia endosymbionts with doxycycline has shown higher antiparasitic efficacy in onchocerciasis and lymphatic filariasis and also improved disease 2.
- A regimen of 6-week/100 mg doxycycline per day sterilized adult female Onchocerca volvulus, and 200 mg doxycycline per day for 4 or 6 weeks revealed 50 and 60% macrofilaricidal effects, respectively 2.
- Reduction of 80-90% of adult worms was observed in bancroftian filariasis with 200 mg/day doxycycline for 4 or 6 weeks 2.
Efficacy of Albendazole
- There is insufficient evidence to confirm or refute that albendazole co-administered with DEC or ivermectin is more effective than DEC or ivermectin alone in clearing microfilariae or killing adult worms 3.
- Albendazole combined with ivermectin appears to have a small effect on microfilaraemia, but this was not consistently demonstrated 3.
- The effect of albendazole against adult and larval filarial parasites, alone and in combination with other antifilarial drugs, deserves further rigorous research 3, 4.
Triple-Drug Therapy
- Triple-drug therapy with diethylcarbamazine, ivermectin, and albendazole is safe and more effective than DEC + ALB for Bancroftian filariasis and has the potential to accelerate elimination of lymphatic filariasis 5.
- All 12 individuals who received 3 drugs were microfilaria negative 1 year after treatment, whereas 11 of 12 individuals in the 2-drug regimen were microfilaria positive 5.
Limitations of Current Treatments
- There is good evidence that albendazole makes little difference to clearing microfilaraemia or adult filarial worms in the 12 months post-treatment 6.
- The review raises questions over whether albendazole has any important contribution to the elimination of lymphatic filariasis 6.
- Trials reporting mf density included small numbers of participants, calculated density data variously, and gave inconsistent results 6.