They usually mix some sort of fruity flavoring in with the meds. Depending on the med, they might still find it bitter. My vet showed me the technique of putting the dropper up at the very upper part of the beak, near where the beak meets the body. Steady your hand against the bird's head. Doing it this way they have less of an opportunity to bite the syringe, and you are positioned closer to the throat already. I figure if a GW bites the syringe hard enough you're going to need a new one, so keep it away from the lower part of her beak
. From that position, drip it in slowly. Too much meds at one time and they can just shake their head and get it out, even when you're restraining the body and keeping the head still, many birds will still try to shake it out. Also, during this, the bird is restrained in a towel.
With Raven, he developed a technique where he'd "pretend" to drink the drops, but really be storing it all in his lower mandible until I released him from the towel, then he shook it all out! I had to touch his throat area below his beak to stimulate a swallowing action after every couple drops to make sure he swallowed it. Some birds are good and easy, others will try anything to not ingest it. Squeeze in a small amount at a time so you can control it and have her swallow it all. If you have a bird who doesn't like to take meds, it can be a challenge and take some practice. They do need to be taking it all and not wasting it by shaking it all over your face and clothing lol. With a large mac, you might try having someone else hold the bird if possible. Give a 'good girl' treat after. It's all kind of hard to explain without pictures. I hope that made at least a little sense.
The problem with medicating the food, is that there (in a lot of cases) can be pieces dropped and they can get a partial dose, or... you waste a portion of meds on a piece of food that they refuse to eat.
Good luck with her continued improvement. I hope she is back to her old self asap!