The drug’s mode of action is not exactly known at present, but experimental evidence indicates praziquantel increases the permeability of the membranes of schistosome cells towards calcium ions. The drug thereby induces contraction of the parasites’ muscle, resulting in paralysis in the contracted state.

mansoni worms induced by praziquantel has been explained by the change in the permeability of the parasite to Ca2+, which results in an increased calcium influx into the worm and an induction of sustained contraction of worm musculatures.

However, Fasciola hepatica and Fasciola gigantica infections are refractory to praziquantel, for which triclabendazole, an alternative drug, is necessary. In addition, larval cestode infections, particularly hydatid disease and sparganosis, are not successfully treated by praziquantel.

Preventing schistosomiasis

1. avoid paddling, swimming and washing in fresh water – only swim in the sea or chlorinated swimming pools.
2. boil or filter water before drinking – as the parasites could burrow into your lips or mouth if you drink contaminated water.

Headache, dizziness, stomach pain, nausea, tiredness, weakness, joint/muscle pain, loss of appetite, vomiting, and sweating may occur. These side effects are usually mild and temporary and may be symptoms of your parasite infection and/or the dying parasites.

In very rare cases, threadworms can spread outside the intestine to the urinary tract or liver, or the vagina or womb in girls or women.

Diagnosis. Schistosomiasis is diagnosed through the detection of parasite eggs in stool or urine specimens. Antibodies and/or antigens detected in blood or urine samples are also indications of infection.