Senegal Parrot named "Kane"; Yellow-Sided Green Cheek Conure named "Bowie"; Blue Quaker Parrot named "Lita Ford"; Cockatiel named "Duff"; 8 American/English Budgie Hybrids; Ringneck Dove named "Dylan"
It's a poison, quite literally, so yeah it definitely could be toxic if not taken at the proper dosage or intervals, but is relatively safe if the dose is adequate and it's only taken short-term and not for long periods of time.