Yes, be VERY careful with your precious bird!! I would be careful about doing a parasite cleanse on a bird.
I almost bought an African Grey last year. They are the smartest of all the birds and my favorite of all the birds. What is your bird's name and what all does he say? I know he does all kinds of cute things, too. I had already named my African Grey and then I backed out. I had a cockatiel at that time (named Greg Norman) and he started chirping one day and NEVER stopped. It drove me crazy, so I found a nice home for him that had other bird friends for him. He was happy and I was happy! That was the main reason I didn't buy the African Grey. I was afraid he would start chirping and never stop.