The Safeguard dose I use is: .25 ml for bantams, .5 ml for standard breeds, .75 ml for large breeds. There is math to get to this, which I can't find at the moment.....Can I ask the dosage amount you give your birds. I'm positive my birds have round worms and I want to treat them, but I'm new to raising chickens and haven't done this before. Also.. Exactly how do you give it to them orally? This is all so confusing..
I use a needle-less syringe that I get at my feed store. A 3 cc syringe will work, it can be hard to find smaller than that locally. As long as you can measure the amount accurately. They are called 'luer slip' syringes. I do this usually early in the morning when they are still roosting, with a shut door. I have 2 dozen birds, so I do each one and put them out of the house after dosing, so once everyone is out, I know I've done them all. Dribble the med into the front of the beak and let them swallow, don't squirt it in hard or they risk aspirating it. Another method is to place the syringe way back to the side of the beak (not in the center of their throat) and do the same. The trachea is in the center of the back of the throat, and you don't want to put it there. There is a good picture on here somewhere that I can't find at the moment, will try to find it and post later. You just don't want them to aspirate. I find that doing .5 ml to the front slowly works fine. Do whichever you are comfortable with.
Here is a video also: