I think that's a mid-range dose of Abilify and a low dose of Celexa. Is the Abilify prescribed for the Tourettes? Does the 13 yr old also have depression? Dosage probably depends on size for how it'll be metabolized and if it's appropriate... based on my fair level of unprofessional knowledge I'd say it should be fine if the kid isn't particularly small, and would trust it if it was prescribed by a doctor.