Does Panacur (Fenbendazole) causes drowsiness or lethargy?

My little feral has to be treated for lungworm. I had her examined, vaccinated and spayed on Wednesday ( during the surgery the vet discovered she was already early in her second pregnancy). Anyway,  she is on day 3 of Fenbendazole. I give her the medicine in her breakfast. I have noticed the last 2 afternoons that she is very tired and sleepy. In the morning, she is peppy and playful. Thanks for any input you all have.

Try doing a google search.  After a brief look myself, it appears that lethargy can be a side effect.  You will want to keep an eye on this and contact your vet tomorrow if she seems worse.

Thank you ShadowsRescue. I did do a google search and most of what I read only addressed nausea and vomiting. Well, the lethargy helps as she is confined to the garage for 8 more days!