A strategic approach to sealice control with Excis may increase the interval between treatments and is recommended. Treatment of sealice before they reach the reproductive stage (eg at Chalimus IV) should help to reduce the number of free-swimming, infective stages released near the fish cages. This should slow down the rate of re-infestation.

Mild transient headshaking/flashing/increased jumping/uncoordinated swimming have been reported in a few fish (< 10%) in < 5% of field trials. The cause is unknown. There have been no permanent effects, no mortalities and all fish are normal within hours of treatment.