Drug interactions with the antihistamines astemizole (recalled from US market) and terfenadine (recalled from US market) can precipitate torsade; these drugs should never be used with class IA, IC, or III agents. Astemizole and terfenadine, in high dosages or when used in combination with the azole antifungal drugs or the macrolide antibiotics, have been reported to precipitate torsade and sudden death.