The OP is just wanting to know about general worming, and most chickens do not have tapeworms.
Most vets prescribe Droncit or Drontal (praziquantel) for tapeworms in pets, in my experience. Praziquantel is available in Equimax horse wormer.
Here is an ancient but very interesting read about...
You can treat with the wormer orally, then start on Corid water at the same time for 5-7 days. It is okay to do both since you don’t know exactly what is wrong. The alternative would be to get a fecal float for worms and coccidiosis if you can get results the same day. Just because she stopped...
If she has finished molting, then using SafeGuard Liquid Goat Wormer is fine. SafeGuard can cause some problems with feather growth in molting hens. Dosage is 1/4 ml given orally once and in 10 days for roundworms. Give it for 5 consecutive days for most all types of worms except tapeworms.
Molt is hard on some chickens. If an illness is going to occur, molting is a time of stress that may make it hard to fight. I would not follow your friend’s advice to put her down this soon. Give her some time. First, look her over to see if she has lost weight through her breast where her...