Newbie needs help with GapeWorm

[davony's chicks]

My peafowl hen has been gasping with her beak wide open and developed a gurgling wheezing sound. From everything I decided to treat for gapeworm. I bought Safe-guard (flenbendazole) dewormer for cattle. I gave her 2 cc syringe down her throat.
My question is..... Do you I only treat once or should I treat again later?? How long does it take to see a result?

There seems to be a lot of opinions on what to treat with but I have not seen anything about how long for results.

Thank you in advance for any help.

 

[saladin]

Did you see any gapeworms? It actually sounds much more like a respiratory condition to me. Gapeworm is actually not very common and generally occurs only in confined areas that become overly filthy. saladin