“…Heroin, cocaine, and methadone use, on the other hand, has been linked to profound hearing loss that is reversible in some cases and irreversible in others. The literature varies on the route of administration, ranging from intravenous injection to oral consumption to inhalation, as well as on the amount and duration of use, ranging from the first episode of use to chronic use lasting over 20 years (Christenson and Marjala, 2010; Ciorba et al, 2009; Fowler and King, 2008; Friedman et al, 2000; Harell et al, 1978; Ho et al, 2007; Iqbal, 2004; Ishiyama et al, 2001; Oh et al, 2000; Rigby and Parnes, 2008; Schrock et al, 2008; Stenner et al, 2009; van Gaalen et al, 2009). Some patients have recovered their hearing after a course of steroids and pentoxifylline, while others have recovered spontaneously, usually within one month of onset.…”