Yeah. I was also on amikacin and cefoxitin but switched to nebulized amikacin once my hearing began to suffer. Oral antibiotics were useless and my doctor, who also moonlighted as one of the leading researchers of NTB, recommended an 18 month course. NTB is never fully eradicated; the treatment just slows/stops the colonization. The guidelines we were working with was that from my first "negative" culture of NTB, I would add 12 months to the regimen. Besides the hearing problems, the treatment worked out beautifully. Haven't had a positive culture of NTB since early 2006.